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Toys Technology Hardware

Beyond Megapixels 438

TheTechLounge points to this "first of a three-part series of editorial articles examining current digital photography hardware, as well as the author's views of what is to come." It boils down to the excellent point that pixel count alone is not the way to evaluate digital camera capabilities.
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Beyond Megapixels

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  • by grahamsz ( 150076 ) on Sunday April 25, 2004 @04:06PM (#8966891) Homepage Journal
    Most people didn't care about resolution in the analog world. The fact that many people considered APS cameras to be better than 35mm is simple proof of this.

    This seems analogous to consumer computer makers moving away from advertising GHz and MB.

    It's what you (can) do with it that counts.
    • by mgscheue ( 21096 ) on Sunday April 25, 2004 @04:11PM (#8966928) Homepage
      I agree that there's much more to it than megapixels. Excellent images can be produced with the 4 MP Nikon D2h, for example. That said, I still prefer film to digital. And I can't think of anyone who prefers APS to 35 mm. People certainly do care about resolution in the analog world. It's why people use medium and large format cameras.
      • by ForestGrump ( 644805 ) on Sunday April 25, 2004 @05:32PM (#8967529) Homepage Journal
        Heh, when I was taking calsses at a CC, I met a guy who worked as a photo tech at a drug store.
        He told me that APS was just crap...and to avoid it like the plague.

        He also said there was some thru the mail company, seattle film, or something like that. they would send people film, you send the film to them for processing. The quality on the film sucked because it was some different technology, and that you were locked into their scheme because you couldn't get it developed anywhere else..

        • by yulek ( 202118 ) on Sunday April 25, 2004 @08:13PM (#8968535) Homepage Journal
          He also said there was some thru the mail company, seattle film, or something like that. they would send people film, you send the film to them for processing. The quality on the film sucked because it was some different technology, and that you were locked into their scheme because you couldn't get it developed anywhere else..

          yep. they basically sold 35mm movie film in 24 frame strips. movie film doesn't have the same high quality requirements as still photography film because any problem in a frame is corrected 1/24th of a second later.

          movie film is therefore much much cheaper per frame than good photographic film. so they were making out like bandits when they hooked someone. and because it doesn't use e-6/c-41 chemicals you had to get it developed either at a motion film lab (not likely) or with them.

          btw, movie film also has a really short shelf life unless kept in special volts at exact temperatures. this is true even AFTER the film is developed!

          seattle filmworks was one a very nasty scam for several decades. a few years ago they finally switched to (really crappy) c-41 film.
        • by Short Circuit ( 52384 ) <> on Sunday April 25, 2004 @08:19PM (#8968567) Homepage Journal
          When I was a kid (10 yrs old, as opposed to 20), my dad had me use that companies film in my cheap 35mm camera on our annual shopping trip to Marshall Fields in Chicago. The reason?

          If you ordered it, they'd send you back a bootable floppy disk that would run a slide show of your pictures. Something not many people did back in 1994.
      • APS had the advantage of allowing the cameras to be quite a bit smaller than 35mm before good quality digital cameras were affordable. Of course, these days, anyone wanting a small camera will get a pocket sized 2MP digital camera.
    • Because APS was as good for small as prints as 35mm was.

      Some digital camera still don't product pictures that look as good as 3x5 film prints, so they are still chasing higher megapixels for that perfect image quality that they desire.

      And with APS or 35mm, people didn't have the capability to crop and enlarge from the comfort of their own home, now resolution matters to them if it means being apple to crop grand ma out of a wide shot and print out a perfect looking picture at home.
      • by jrumney ( 197329 ) on Sunday April 25, 2004 @04:49PM (#8967204)
        Some digital camera still don't product pictures that look as good as 3x5 film prints, so they are still chasing higher megapixels for that perfect image quality that they desire.

        .... and print out a perfect looking picture at home.

        I think that demonstrates the problem here perfectly. People are chasing bigger MP, not because 2 or 3 MP wasn't sufficient to give decent looking snapshots, but because they are trying to print those snapshots at home and then comparing them to professionally printed photos from film.

        Send your photos off to a professional company, and pay them 20c per photo to print them on their $10,000+ professional laser printer instead of pissing about with your $100 inkjet that is probably costing you more than 20c per picture in overpriced ink cartridges anyway. Then you will see that even 2MP gives at least as good results as a compact film camera, and 3MP with a decent lens probably comes close to a 35mm SLR.

        • by Veteran ( 203989 ) on Sunday April 25, 2004 @08:07PM (#8968490)
          The HP 7960 8 ink printer produces prints which are superior to photographic enlarger prints. Having done extensive darkroom work I think that scanned film with a 7960 is currently the way to go (up to 8.5 x 11 inch prints that is.) Are the inks expensive? Yes, is the paper expensive? Yes. Are the results superb? Yes.

          Why do I do my own printing? A $10,000 printer at a camera store is only as good as the person operating it. If I screw up my prints I have only myself to blame. For serious work I want at least a 6x6 cm negative, which is about equal to 64 megapixels.

          For snapshots of people - which are never going to be enlarged bigger than 5" x 7" I suggest an inexpensive Argus D450 35 mm point and shoot with an aspheric plastic zoom lens, built in automatic flash, motor drive and a 10 year warranty. The camera, which came with 2 batteries, and a roll of Kodak 400 speed color film sold for $17.53 (including tax) at the local Wallmart. For this type of photography I don't know of a digital camera which can come close to it for the money.

          Do I own digital cameras? Yes, but I don't think they are quite ready for primetime yet.
          • Whether digital or film is cheaper depends a lot on how many pictures you want to take and how many prints you want to make. A cheap film camera is probably a good choice if you're going to take a roll of snapshots once a year at Christmas and share one set of prints with your family. But if you want to take a few thousands photos a year and share them with everyone you know, the digital will pay for itself in reduced film, developing, and printing costs in fairly short order.

            Digital also has some real

          • The HP 7960 8 ink printer produces prints which are superior to photographic enlarger prints.

            With film enlargement, the choices of paper and film are what impacts the quality the most. I would agree that the current digital workflow rivals film for quality and blows it away for control, but traditional enlargements can and do frequently look better. I personally find HP's greens a little sickly.

            I don't trust any inkjet manufacturer when they claim their prints are archival just yet. Check back with me
    • to tell you the truth, i've not taken a picture with a digital camera that i've not resized to something smaller than 640x480. even that's pretty large, i usually size them down to 320x240 so they look like pictures and not overly magnified illustrator documents.

      i mean, 1600x1200 is only 2MP, and that's freakin' huge. the only reason i'd need something like 8MP (~3200x2400) would be if i was taking pictures of blueprints, bond-style, or needed a picture to be blown up to letter-sized proportions or large
      • by tzanger ( 1575 ) on Sunday April 25, 2004 @04:26PM (#8967041) Homepage

        I have a Canon PowerShot A60 -- I chose it over other brands because I really like how my Canon Rebel EOS works and the A60 is very similar. 2.2MP isn't a hell of a lot, but it's enough to get 5x7 prints and have a chance in hell of it looking close to what I can get with a regular camera.

        I completely disagree with your statement that digital cameras aren't used for prints -- I take a bazillion pictures, throw them up in 720x480 for the web for grandma and grandpa and then they tell me specifically which pictures they'd like prints of. I take the original 2.2MP JPEGs and give them to my film guy -- he touches them up and makes real 4x6 or 5x7 prints for me. They look fantastic and everyone's happy.

        True, the bulk of my pictures stay in 720x480 but it's really nice to be able to get a 5x7 out of it should I want it. The amount of time I want 8x10s is next to nil; I go to the same photographer and get really good digital pictures taken in that case. (He's all but completely moved to a full digital studio.)

      • by ipfwadm ( 12995 ) on Sunday April 25, 2004 @08:05PM (#8968479) Homepage
        I have a 3 megapixel camera, and I've gotten pictures from it blown up to as large as 16x20. In fact, I have 2 of them on the wall of the room I'm sitting in right now. If I look at them from 6 inches away, I can tell there isn't as much detail as I would get from film. But when I'm sitting 6 feet away as I am right now (and 99% of the time), you could never tell the difference. Same with the dozen 11x14s I have around my apartment.

        In fact, when I brought the prints to a store to get them dry mounted and I told them they were digital, the response was "THESE are DIGITAL?" The fact that the enlargements were done with a photographic process vs. a printing process certainly helps. The 4x6 prints I get look just as good as anything I've gotten from film, but, as another poster stated, you can't get that kind of quality from your $99 inkjet.

        Check out [] if you want to see the pictures I've gotten blown up (and a lot of others); they're all from a 13,000-mile trip around the U.S. last summer. The ones I've gotten at 16x20 are Bryce Canyon [], Crater Lake [], the mountain next to Mt. Dana in Yosemite N.P. [], and the Grand Tetons [].
  • It always... (Score:5, Insightful)

    by soul_cmd ( 654552 ) <soul_cmd@co[ ] ['mca' in gap]> on Sunday April 25, 2004 @04:07PM (#8966900)
    comes down to the lens. No matter how many billions of pixels you fit behind it, the lens is going to determine the first determining factor of the photo quality. It's certainly not the last (thus we move to 3 CCD systems etc. for better color reproduction) but the lens.. is always going to be the biggest factor.
    • Re:It always... (Score:2, Insightful)

      Well .. in this case .. it's not the lens that make the most difference .. it's the size of the photosite ..
      simply stated .. the current 6mp - 14mp DSLR on the market has a larger photosite .. giving the current DSLR higher signal to noise ratio compared to the 8mp consumer digicams.
    • Re:It always... (Score:2, Informative)

      by slabbe ( 736852 )
      And even with a sharp lens its easy to screw it up by not holding the camera steady. I.e. a good old tripod can be rather useful.
    • Re:It always... (Score:2, Interesting)

      by S.Lemmon ( 147743 )
      The article seems to be making the argument that a smaller format sensor won't be as sensitive as a larger sensor, but I'm not sure I buy this.

      The example he gives of buckets of water is flawed, since falling rain isn't *focused* like light is. Light entering a lens is just being focused on a smaller area. Sure the area is smaller, but it's also brighter.

      A larger sensor just requires the projected image to be spread out further. Of course, maybe if you got too small, you'd run into the same limits optical
      • Re:It always... (Score:5, Informative)

        by sql*kitten ( 1359 ) * on Sunday April 25, 2004 @05:08PM (#8967331)
        The article seems to be making the argument that a smaller format sensor won't be as sensitive as a larger sensor, but I'm not sure I buy this.

        A smaller sensor is more noisy and more prone to chromatic abberation. Which is why my old EOS D30 with a large 3MP CMOS sensor produces better pictures than Sony's F828, which crams 8MP onto a tiny CCD. 3MP prints great up to 9x6" and is uable at 12x8". It's difficult to get a good print off a CCD camera above 7x5". Larger images don't need to be distorted as much by the lens to be focussed down onto a larger sensor, and that matters. More photons per unit area matters for faithful colour reproduction.

        But like another poster said, most of these images are destined to be viewed only on screen, so most of the resolution is wasted. About the only thing it's useful for is giving the freedom to crop.
      • by SuperBanana ( 662181 ) on Sunday April 25, 2004 @05:44PM (#8967606)
        The article seems to be making the argument that a smaller format sensor won't be as sensitive as a larger sensor, but I'm not sure I buy this.

        Well, it's fact. The larger the surface area of each cell, the better signal to noise ratio you will get. CMOS yields better quality than CCD, as well- although the margin has dropped as CCD sensors and the electronics behind them have improved faster(due to everyone and their grandmother working with CCDR sensors) than CMOS.

        This phenomenon can be seen clearly in both the non-CMOS 14 megapixel Kodak 14n, or the Sony F828, which has a VERY tiny 8 megapixel CCD sensor. Both are horrendously noisy at their lowest ISO settings.

        My Canon 10D has better noise characteristics at about 400 ISO than my Canon G1 had at 50 ISO, and 400 is about the limit I feel is appropriate for an 8x10. For images resized to 800x600 for, say, large images linked off a website, ISO 800 or 1600 still yields pretty decent images. The example he gives of buckets of water is flawed, since falling rain isn't *focused* like light is. Light entering a lens is just being focused on a smaller area. Sure the area is smaller, but it's also brighter.

        Light is focused, but it's also made up of particles. Further, the smaller the sensor, the smaller the lens. The smaller the lens, the less light is gathered.

        Smaller sensors also require much more precise optics and focusing systems(or smaller apertures, limiting light input even further). Tiny sensors are also very prone to flare.

    • Re:It always... (Score:4, Informative)

      by fearlessfreddy ( 468996 ) on Sunday April 25, 2004 @04:39PM (#8967131)
      Actually, it is important to match the quality of the lens to the resolution of the CCD. Too fine a lens will cause aliasing artifacts. This can be understood by the Nyquist Theorem.

      Once an aliased image is captured by the CCD, no amount of image processing can remove the artifacts. That is why high end digital cameras like the Nikon D1 contain an optical low-pass filter between the lens and the CCD that purposefully degrades the quality of the lens assembly.
      • Re:It always... (Score:5, Informative)

        by wildsurf ( 535389 ) on Sunday April 25, 2004 @10:02PM (#8969067) Homepage
        Too fine a lens will cause aliasing artifacts. This can be understood by the Nyquist Theorem.

        This depends on the shape of the CCD active areas that are used to capture photons. In the "worst case" where the receptors are essentially discrete points on a grid, an optical blur is needed so photons that would otherwise land in between the sensors have a chance to be captured. In practice, I would guess that the sensors cover about 50% of the usable area, so the remaining 50% must be made up with low-pass filtering to avoid aliasing. (Think of filming headlights; if they're in focus they'll be two discrete points of light, but as you defocus the lights will expand until they overlap.)

        A similar problem also comes up in motion video; the aperture is typically open 75% of the time, then closed 25% while the film advances. This results in motion aliasing such as helicopter blades and wagon wheels spinning backwards, etc. Digital video may be able to substantially reduce this problem, but ironically most people have grown accustomed to it, to the point where non-aliased video simply doesn't "look right."

        The Foveon approach is a step in the right direction for image capture, since the Bayer interpolation from most other cameras is prone to all sorts of artifacts. Perhaps a camera could be built that would expose the same CCD array through red, green and blue filters in sequence, then apply software to compensate for slight motion between frames.

        Similarly, imagine a camera that would expose the CCD for 1/10,000 of a second, then 1/1000, then 1/100, then 1/10, and combine the resulting frames into a single high-dynamic-range image. When the sun is millions of times brighter than the shadows, [0..255] simply isn't going to do justice.

        In my opionion, the next few years of digital photography is going to be mighty interesting.
  • wait wait... (Score:3, Insightful)

    by toast0 ( 63707 ) <> on Sunday April 25, 2004 @04:10PM (#8966922) Homepage
    more isn't better?

    at least it looks like bigger is still better, the sensors the author likes are physically larger.
  • by vlad_petric ( 94134 ) on Sunday April 25, 2004 @04:12PM (#8966931) Homepage
    People buy megapixels instead of quality for the same reason they buy gigahertz instead of performance: it's a simple quantity (number) and it's very easy to compare two products by this number (although sometimes it's meaningless)

    With digicams, megapixels only matter (these days) for large prints, especially since most monitors these days are used at 1024x768, which is ... 768 kPixels :).

    How about using SNR ? I know it's difficult to compute, but reviewers could use VHQ analog film, film-scan it and compare the output to digital output.

    • by Morgahastu ( 522162 ) <bshel@WEEZERroge ... fave [ ]ds name > on Sunday April 25, 2004 @04:20PM (#8966997) Journal
      It's not just for large prints, it's for creative freedom.

      With a high megapixel camera I can take a picture of a statue from far away, get home and crap 3/4 of the picture out and still be left with a picture that's high quality enough for a print.

      I have a 2 megapixel camera and it's good (not great) for 3x5 prints but I am not able to crop any of my picture or the quality loss is evident in prints.
  • I work in retail and occasionally sell digital cameras. People come in talking about how bad they want an 8 megapixel camera. When I ask them why they want 8 megapixels they respond usually, "because it's better than 5 megapixels" the they proceed to tell me it's going to make their 4x6 prints really nice...

    I hate people

    • ...wait until you meet your colleagues that actively try to push 8 MP cameras on consumers that want 5 MP, because they're higher profit. That's one of the reasons I like to review products online rather than ask salesmen for help. Granted, most are trying to be helpful but I've definately overheard advice that makes my stomach cringe.

    • by C10H14N2 ( 640033 ) on Sunday April 25, 2004 @04:45PM (#8967175)
      If you were making an optical print, it would take 8.6 megapixels to equal the effective resolution of the emulsion on a 4x6" sheet of photographic paper. There ARE inkjet printers out there that will reproduce in excess of 2000dpi, but most people don't spend the $2-10k necessary to have that capability.

      So, yeah, knowing they have a at best a crappy 600dpi printer on their desk, they're being idiots, but not complete idiots as in both theory and practice, an 8MP image would look almost as good as a 35mm print... of course, their idea of "35mm print" is also "using a 3mm lens on a $10 disposable camera using $2 film" so, suffice it to say, their idea of "film quality" is already pretty sad.

    • they proceed to tell me it's going to make their 4x6 prints really nice...

      If you get a lab to print your JPEGs, they're probably going to use something like a Fuji Frontier, which uses lasers to print onto photographic paper like Fuji Crystal Archive. This is professional-quality printing, and side by side is noticeably better than what even a good home inkjet can do. A Frontier prints at 300 DPI. Tell 'em that anything above 1800x1200 pixels is wasted anyway!
  • by dexterpexter ( 733748 ) on Sunday April 25, 2004 @04:13PM (#8966939) Journal
    The biggest determining factor to me in buying a good digital camera is the optical zoom. With so much focus put on the number of megapixels and digital zoom (which, in my opinion, is better done in Photoshop anyways), the optical zoom is too often forgotten and hard to find in most "affordable" digital cameras. Without the optical zoom, one is limited to the same twelve-foot-away pictures that is great for people who only want to take pictures of friends and family standing in front of things, but is really useless if you want to get a good close up.

    For example, this picture I took with my decent megapixel digital camera, my first time using it [] was a terrible disappointment because it was a great shot ruined just based on my not having the proper optical zoom capabilities.
    (And my mistake in buying a camera that I thought would be top of the line, and stupidly didn't notice the difference between digital and optical zoom, this being my first move off of traditional cameras.)
    • The only reason to use the built-in digital zoom instead of zooming in photoshop is when you're using JPEG. If you use lossless compression or no compression at all photoshop is (probably) better.

    • this picture, your first time using this camera.

      although most cameras are purchased prior to an impending expected use, is it fair to blame a camera the first time you used it? most photogs know they need to use a camera for a while before they can expect the best the camera can produce.

    • i agree with you.

      unfortunately, i haven't seen many (if any) cameras with an optical zoom capability higher than 3X. they'll advertise the "859869X digital zoom" all day long, but digital zoom is an absolutely worthless feature, in my opinion.

      i imagine they make such a big deal of it in order to attract the dolts that number-shop.

      • by Hawthorne01 ( 575586 ) on Sunday April 25, 2004 @04:42PM (#8967151)
        unfortunately, i haven't seen many (if any) cameras with an optical zoom capability higher than 3X.

        Anything longer than 3x optical zoom requires some optical tirickery, which results in a) higher price if done right or b) lower quality if it's done cheaply. And beyond that, the more glass = slower lens f-stop, means more need to use flash (and shorter flash when you do) or it means having to use a higher IS) equivalent, which means more noise on your pictures (think gain-up).

    • by giminy ( 94188 ) on Sunday April 25, 2004 @04:29PM (#8967059) Homepage Journal
      This photo looks more like your lens just didn't let in enough light, so your camera automatically dropped the shutter speed. Probably you couldn't hold it perfectly still during the longer exposure and schlorp, blurred photo. Having an optical zoom would only make things worse, as the lens lets in less light when zoomed in.
    • by efatapo ( 567889 ) on Sunday April 25, 2004 @05:21PM (#8967456)
      Slashdot isn't a photography website, but I'll respond to this anyways. Optical zoom wouldn't have helped you much here. As others have responded, it probably would have hurt more than anything.

      The shutter was open for 1/8 second. Usually the most stable hands can only hold a camera still for 1/focal length. ie, for a standard camera you shouldn't shoot any slower than 1/30 of a second.

      Having a longer focal length would have exacerbated the problem. What you need here is a greater light sensitivity (higher ISO). A higher ISO would have allowed you to shoot with a faster shutter speed.

      I would suggest reading up a bit at [] or [] before buying a new camera.

      If you want to see my credentials for making this comment take a look at: []
  • It definitely not about the megapixel, but how else do you do a quick little statement that identifies the quality of a digital camera. When you deal with a digital as aposed to a analog camera it is like talking about the film as well as the hardware.

    Maybe we could translate it into ISO instead?

    • If we can't use just one metric to identify the quality of a digicam, we'd have to do with something like a (megapixel,sensor size,optical zoom) triplet. Most of us already know to look for more than one feature while buying PC's. It would be nice if somebody well-versed in the mysteries of digital camera technology would standardize the set of features that I should be looking for as a consumer....
  • Mars PanCam (Score:3, Insightful)

    by PhrostyMcByte ( 589271 ) <> on Sunday April 25, 2004 @04:13PM (#8966948) Homepage
    Isn't Spirit's PanCam using this same idea to capture images?
  • by way2trivial ( 601132 ) on Sunday April 25, 2004 @04:15PM (#8966960) Homepage Journal
    Sonys new touted digital cameras are RGBe or emerald, every 4 pixles are Red Green Blue and Emerald, purportedly because our eyes are twice as sensitive to green, and this makes better pictures (according to sony).

    if we are so 'green aware' why don't inkjet printers ever have green ink?

    • inkjet printers don't have red or blue inks, either...

      you're forgetting that light and pigments combine differently to produce certain colors.

    • There are different ways to produce color; you can start with black and add red, green, (maybe emerald), and blue, or you can start with white and subtract cyan, yellow, magenta (and optionally black). Cameras and monitors use additive color while printers use subtractive color. More info. []
    • if we are so 'green aware' why don't inkjet printers ever have green ink?

      Well, some of the more specialist photo printers that contain more than five colours of ink do now include a greenish shade of ink. The main reason though is that most hues of light can be simulated by mixing varying intensities of red, green and blue. This is an additive model where 100% of red, green and blue is white.

      For prints however, a subtractive model is used - what you are actually seeing when you look at a print is a t

    • A standard bayer pattern is already 'double density' of green sensitive colours.

      Some more advanced patterns use RGBY, where Y is munged Red and Green data- it's backed out in the sensor calculations.

      The fastest (ISO rating) sensors use CMY (but I forget if its doubled M or doubled Y, or even if the last one is G for colour accuracy).

      Ask yourself why- cyan is the opposite of red- how is cyan made? Magenta(R+B) and Yellow(R+G). Only the 'red' can pass thru, thus 1/2 the light is lost.

      Sadly the matrix th
  • Of course you have to remeber that a camera is only good as the person behind it so no point in spend $1000's on a camera if you aren't accomplished

  • by KalvinB ( 205500 ) on Sunday April 25, 2004 @04:15PM (#8966966) Homepage
    When you're dealing with digital you quite simply need pixels. You need to decide what size pictures you intend to print or whatnot and get an MP count to match. You can't get a 1.0MP camera and do large prints of any quality.

    Of course you also need picture quality. But it really doesn't matter how good the colors are if you're only getting a postage stamp image.

    I have a 2.0 megapixel camera which I intend to replace eventually. Not because of the pixel count, but because of the image quality. I have a few pictures where a small branch got just a bit into the frame. The camera focused on that little branch and blurred the rest of the picture. There's no manual focus so all I can do is watch what's in the view carefully.

    It also doesn't react intelligently to low light. Although with a bit of modification I can turn that into a feature as I can take time lapse photos to get good pictures in very low light.

    As with all things, you need to pick the versions with the features you need.

  • by enrico_suave ( 179651 ) on Sunday April 25, 2004 @04:18PM (#8966986) Homepage
    CCD size/quality
    Quality of Glass

    Then look at MP and other features (including price/battery life other doodads)

  • by isny ( 681711 ) on Sunday April 25, 2004 @04:20PM (#8966996) Homepage
    Check out this link []. It details a bit on how the spirit rover only has a 1 megapixel camera on board, yet delivers IMAX quality images.
    From the article: "NASA's Spirit Rover is providing a lesson to aspiring digital photographers: Spend your money on the lens, not the pixels. Anyone who has ever agonized over whether to buy a 3-megapixel or 4-megapixel digital camera might be surprised to learn that Spirit's stunningly detailed images of Mars are made with a 1-megapixel model, a palm-sized 9-ounce marvel that would be coveted in any geek's shirt pocket. Spirit's images are IMAX quality, mission managers say. "
    • by poptones ( 653660 ) on Sunday April 25, 2004 @04:43PM (#8967157) Journal
      The rover also has the luxury of having very few moving objects to contend with, and being able to remain in a very precise location for extended periods of time. It would not be so easy for me to take 100 pictures of grandma from the exact same position with different dithers applied to the image over a period of hours - she's not likely to sit still for that, unless grandma's finally done her last moving around.

      I've done experiments with my 3MP camera, taking multiple shots from the same angle and layering them in photoshop. The enhanced resolution can be downright breathtaking, but the practice is only practical for still lifes and landscapes. What are you going to do with that 1MP camera when you want a high resolution image of janie's first smile?

    • by morcheeba ( 260908 ) * on Sunday April 25, 2004 @04:49PM (#8967206) Journal
      I wouldn't want this in my pocket. The secret isn't in the camera; it's in the tripod. Being able to hold it still (and the fact that the subjects aren't moving) allows merging different pictures -- to get color resolution (using the color wheels) or spatial resolution (by merging into a panorama).

      The lens is nice, and being fixed-focus and fixed-zoom helps with the quality over a consumer-grade camera, but the tripod is more important.

  • by Kjella ( 173770 ) on Sunday April 25, 2004 @04:23PM (#8967013) Homepage
    ...electronics: Cheap ...optics: Expensive

    Look at screens. Graphics cards have improved massively (electronics), screens (optics) used to be 1024x768 quite a while back, and typically aren't more than 1600x1200 now. The LCDs will hopefully change that though, since they're much more scalable (make more pixels) than a CRT (move beam faster).

    Same with digital camera. The back-end is getting much cheaper, multi-MP CCDs and other electronics, but good optics in the lens is still damn expensive.

    I read a piece recently about HDTV cameras. There were rumors that a certain camera would be sub-10.000$. The official comment basicly said "we can't tell you the real price yet, but you're smoking crack. the lens alone is in the 7-9.000$ range".

    That being said, most digital cameras today should be just fine, if you don't try to take "impossible" pics. If the sun is saturating the CCD, it won't happen. If there's light casting ugly shadows, fill it in or you'll never get rid of them. There's a lot more bad photography than bad cameras...

  • It's the lens (Score:3, Insightful)

    by Stevyn ( 691306 ) on Sunday April 25, 2004 @04:23PM (#8967019)
    Megapixles don't mean shit if the lens the light had to go through is distorted in a bad lens. Nikon cameras are more expensive mainly because of this. Take the camera on the mars rover for example. Not a 10 mp camera, but a 1 mp with a damn good lens. Yeah, they also break the colors up but that's not the point.

    Manufacterers like kodak and hp don't have a lot of experience in camera design and that's why they're so cheap compared to a good nikon or canon digital SLR with much much better lenses.

    As in anything with computers, you get what you pay for, the problem has been though that most people compare cameras based soley on the number of pixels.
  • Sigma SD10 (Score:5, Informative)

    by tantalus ( 466821 ) on Sunday April 25, 2004 @04:24PM (#8967024) Homepage
    The camera sitting at the extreme of the low megapixel, high quality spectrum is the Sigma SD10, which is the only camera to use Foveon's x3 sensors to capture three colors per pixel. This results in a very high quality image, even though the total pixel output is ~3.4 megapixels. I would like to see some of the other major players put out cameras with Foveon's tech. With competition, we might see further refinement of the design.

    Here's a comprehensive review [] of Sigma's camera.
  • Here's [] a link (MSNBC, yeech!) about the cameras on the Mars rovers. They only have a one megapixel sensor, but damn fine optics (as you would expect.)
  • by BitWarrior ( 692600 ) on Sunday April 25, 2004 @04:26PM (#8967037)
    Having just purchased the new Nikon D70 digital SLR camera I can say that pixel count is definitely not what you should look at. At 6.1 megapixels, the D70 is relatively high but some of my friends derided me for not getting an 8 megapixel non-changeable lens camera. Trying to explain to them the benefit of having a real SLR body, the ablity to change lenses, manually adjust all settings etc. is a lost cause. Many people don't understand that although I spent twice as much for less resolution I can do things with this camera that they could never dream of with a traditional digital camera, regardless of resolution. Light sensitivity, signal to noise and optics all rank above resolution in my book. The ability to manually adjust all settings is right up there too.

    Of course if you're just taking snapshots to send to grandma then forget everything I've just said :-)
  • by loraksus ( 171574 ) on Sunday April 25, 2004 @04:29PM (#8967061) Homepage
    An 8 megapixel ccd behind a cheap lens is going to look worse than a 1 megapixel ccd behind a high quality lens. Look at the pictures of mars, they were taken using a 1mp camera.

    Of course, the additional detail is nice. But to be really usable to blow images up (which is probably the only reason for going higher than 4-5mp), the following problems have to be solved.

    1. Noise has to be reduced. Especially in dark pics. Less of a problem now, but still an issue. Of course, if you're taking a 8mp camera and printing out an 8x10, you probably won't be complaining. Zoom in to 300-400% and you will be easily able to see it (and all the stuck sensors, but that is another story).

    2. The lens is good enough to resolve that detail.
    No, your made in china $5 lens will not be good enough. There is a reason professional film cameras have "big ass lenses".

  • by AtariDatacenter ( 31657 ) on Sunday April 25, 2004 @04:30PM (#8967064)
    I personally am waiting for a good Megavoxel camera. If you think pixels are good, imagine the images that can be rendered with voxels! It is incredible! ;)
  • Snap (Score:4, Insightful)

    by Deanasc ( 201050 ) on Sunday April 25, 2004 @04:34PM (#8967093) Homepage Journal
    I'd like a digital camera that responds as quickly as a film camera. I hate holding down the button and waiting for the camera to decide if it will take the picture or not. I want a digital camera that will take the picture when I press down the button not 1/2 to 3 seconds later.
    • Re:Snap (Score:5, Insightful)

      by aussersterne ( 212916 ) on Sunday April 25, 2004 @05:14PM (#8967397) Homepage
      All of the digital SLRs (i.e. Canon D30/D60/10D/1D/1Ds/300D, Nikon D1X/D1H/D2H/D100/D70, Fuji S1/S2/S3, Olympus E-1/E-10/E-20, Sigma SD-9/SD-10, Pentax *istD, Kodak DCS-14N) will essentially let you click and take photos as fast as you can, zero delay, not feeling any different from an SLR film camera at all.
      • Re:Snap (Score:3, Informative)

        by donutello ( 88309 )
        All of the digital SLRs (i.e. Canon D30/D60/10D/1D/1Ds/300D, Nikon D1X/D1H/D2H/D100/D70, Fuji S1/S2/S3, Olympus E-1/E-10/E-20, Sigma SD-9/SD-10, Pentax *istD, Kodak DCS-14N) will essentially let you click and take photos as fast as you can, zero delay, not feeling any different from an SLR film camera at all.

        It's still not the same - particularly with the lower end digital SLRs.

        While the single-picture lag may not be so great, the key number is buffer size. The 300D, for example has a buffer size of 3 i
    • My camera (an Olympus 2020z) is constantly doing apature(sp?) and shutter adjustments, so those are ready when I'm ready to take the picture, the only thing it has to do is focus. The nice thing about this camera (in addition to being an awesome consumer level camera), is I can hold the button halfway and it focuses, and the rest of the way so I get an instant picture. There is also no delay if I put it into manual focus mode. I can also set it to manual apature, shutter, and ISO mode, or any combination
  • by Hawthorne01 ( 575586 ) on Sunday April 25, 2004 @04:36PM (#8967112)
    Let me just add "Hell-freaking-yeah" to what that article says. My poor old 6 megapixel Phase One back would be sneered upon by all the MegaPixel Nazis. The fact that it kicked out an 18mb TIF and used Hasseblad glass is lost on them.

    One thing I hope future articles touch on is ergonomics. Unlike SLR's, which have had the same basic layout since the Exaktaflex, digital cameras are a hodgepodge of knobs, buttons and dials, laid out (apparently) at random at times. And the difference in features between cameras of the same pixel size can be stunning.

    When people as me what's the best camera out there, I usually tell them find one that they find first easy to use, is a camera-brand (better glass), and has a decent image size. No amount of features will make up for a missed photo due to fumbling with a camera, and what's important to me (manual controls, accessory shoe, RAW/TIF, etc) may not be important to them.
    • by mozumder ( 178398 ) on Sunday April 25, 2004 @06:14PM (#8967854)
      Agree that ergonomics should be prioritized. It's amazing how many useless "features" the camera makers are adding to jack up their marketing feature list at the expense of usability. There are just WAY too many options. They could get rid of almost all the buttons on a Digital camera for even the pros. I really wish they would simply cut out switches and menu options and make it so that you DON'T need a manual to operate it. My favorite camera is still a fully-manual 35mm Nikon FM2. Either that or an 8x10.

      Things I wish manufacturers did:

      1. Store data in RAW format. (Thanks to Sigma for pushing this.) This get rid of the useless "low/medium/high quality" switch on the camera. There goes one pointless switch.

      2. Store all data at the highest resolution. Get rid of the "small/medium/large" switch. If I needed to store more pictures on my card, I would have bought a higher-capacity CF drive. I can get 4GB models now. That should be enough to store hundreds of pics. Another pointless switch, gone...

      3. Get rid of in-camera white-balance setting, and do this on the computer or laptop or even palmtop to simplify the camera and force the complexity outside. (Again, thanks to Sigma) This can be done on the computer if needed with the RAW file. Most amateur users have NO idea what the hell white-balance means anyways. A third pointless switch gone..

      4. Get rid of the Priority switches- Aperture, Shutter, Etc.. Instead, allow the user to adjust the Aperture & Shutter on a lens ring. The ring can also have a setting for Auto. This can also be done for focusing with a Focusing ring. There- 3 buttons eliminated just like that.

      5. Get rid of on-camera flashes settings (Keep the wimpy on-camera flash if you must, but leave it on Auto always, and auto-disable when external flash is connected) Pro photographers would have an external flash anyways, and any flash settings can be made on that. Another switch, gone...

      There's so many useless switches on a modern Digital SLR that can be completely thrown away and still provide all the functionality anyone would want.

      Some people may want all these useless features.. for them the camera vendors can have their own special overfeatured model. I would rather have one that's simple and obvious... The first Digital SLR vendor that comes out with a Camera that DOESN'T include an INSTRUCTION MANUAL, I'm buying.
      • 1. Storing data in RAW format is always a good thing for non-casual users. But for many jpeg files are all they will ever use.

        I think all high-quality cameras now can store RAW image formats.

        2. Store at the highest resolution. Well, maybe, although it's a great way to save memory which ain't cheap or as large as I'd like to have it yet.

        3. If you can shoot in RAW mode then you don't need the camera to do white-balance and you can do it in the computer where you have the horsepower and GUI to do it right
  • Depth (Score:3, Interesting)

    by slabbe ( 736852 ) on Sunday April 25, 2004 @04:37PM (#8967118) Journal
    Even with good lenses and modern low noise sensors, digital cameras has a rather narrow exposure range as compared to classical photography. Shooting with negative film you can get something like twice the exposure range, compared to any ordinary digital camera (i.e. you will be able to see more details in both the dark and light areas of your photo)
  • Obvious (Score:5, Informative)

    by ajs318 ( 655362 ) <`sd_resp2' `at' `'> on Sunday April 25, 2004 @04:46PM (#8967184)
    The most important part of any camera is the lens. There are two main problems with lenses. Chromatic aberration causes colour fringing due to the focal length of the lens being different at different wavelengths. It can be corrected by using compound lenses {one positively-dispersing lens and one negatively-dispersing lens} or low-dispersivity materials. Spherical aberration causes distortion of the image due to the lens surface not being perfectly spherical, and thus the focal length varying over the surface. It can only be corrected by grinding lenses well.

    A bad lens will produce a bad image regardless of the image sensor. Sometimes an image sensor will not have enough resolution to detect the distortion due to chromatic and spherical aberrations. But when the same manufacturer slaps a new sensor on last year's lens, the new sensor can pick up better on the aberration and the pictures end up looking lousy.

    Another feature to bear in mind is hardware {optical} zoom. Don't buy a camera without it and don't reject a camera for not having software {digital} zoom -- your favourite graphics editor can do this for you.

    Cheap image sensors are invariably noisy. Big pixels can hold more initial charge, therefore can accept more light in the course of an exposure. The sensor will only be saturated in really bright light, and the amount of charge remaining on the pixel {which is a measure of how much light didn't hit it} can be measured more accurately: one "unit" on the ubiquitous 0-255 scale represents many electrons. But more silicon costs more money. Small pixels don't have the same capacitance, so can't accept as much light before becoming saturated -- you have to run a shorter exposure. And the number of electrons per ADC count is smaller. The net result of having a higher density in the image sensor is that even in bright light, the resulting pictures will look a little bit as though they were taken in poor light. Of course, you can remove the noise by downsampling, but then you lose the benefit of the higher-res sensor.

    And what's with the confusing term "digital SLR" ? As far as I can see, all digital cameras with LCD viewfinders are by definition SLRs, since the same lens is used for viewing and taking the picture.
    • Re:Obvious (Score:3, Interesting)

      by jwitch ( 731255 )
      Some interesting points there mate. However, don't dismiss software zooming as being useless. The software zoom on most digital cameras take the picture, then software zoom, then convert the raw data into formats such as jpg. If you were to just convert to jpg and use software to zoom, you would be zooming in on the artifacts of the jpeg compression. Therefore, software zooming can give you that little ooomf. I'm ignoring the fact that some cameras don't compress the raw data though. In which case, ju
  • by Ohreally_factor ( 593551 ) on Sunday April 25, 2004 @04:49PM (#8967207) Journal
    First of all, no one has mentioned DYNAMIC RANGE yet. This is the range between absolute black and absolute white. Whether you are using film or digital, this range is crushed compared to the human eye. Digital dynamic range tends to be worse than film, which is one reason film isn't going to go completely away any time soon.

    Greater dynamic range will give you better details in your shadows and highlights. This is very important for the serious photog, although probably not important for snaps of your kid's Bar Mitzvah.

    The other thing that matters is the actual size of the CCD. Manufacturers are using various technical tricks to squeeze out more pixels from the same size CCD, and the results are sometimes pretty bad. The worst problem I've seen was purple fringing in bright red objects that were backlit. Totally ruined an otherwise beautiful photograph.

    The bigger the CCD the better.
  • Why digital camera? (Score:5, Interesting)

    by russianspy ( 523929 ) on Sunday April 25, 2004 @05:00PM (#8967273)
    Why not shoot in film and use a film scanner? I've got a 30 year old (Minolta X-700) camera that has been with me through a lot. The thing will not die and just keeps on going. I just have to change the battery once a year or so. I usually develop my photos at a grocery store. Ask to have it developed and cut only - no prints. It costs me 1.25 per roll and I have it in about 20 minutes. Later I scan them in myself, get 11 Megapixel images with 48 bit color, scanned 8 times to minimize noise. (They're about 62 Meg TIFF images) that I can print with up to 13x19 on my Epson 2000P printer. The best part is, in 5 years I'll buy the newest and greatest film scanner and I have the option to re-scan the images at 20 Megapixels or whatever. That's my solution at least. By the way, the scanner was only 500CAD ;-)
  • by system_trader ( 730434 ) on Sunday April 25, 2004 @05:14PM (#8967394)
    The article is a bit misleading, and perhaps wrong. It exchanges one myth for another myth. Indeed megapixels alone do not define resolution. However, CCD size isn't the answer either!

    The article fails to address the issue of optical resolution, i.e. lens quality and aperture. Does the number of pixels act as the resolution limiter, or does the quality or size of the lens limit resolution? Many consumer cameras use poor quality small lenses, but boast of large numbers of pixels. Since CCDs are cheap and good lenses aren't, why not over sample the image enough so the consumer thinks they're getting a superior image, and has to pay more for flash memory? The number of pixels can be irrelevant for a camera with a small or cheap lens. Larger aperture lenses will always resolve better, as is the case with all imaging optics anywhere in the spectrum between telescopes and microscopes. Cameras are no different.

    The reason professional cameras are better is not just because the CCD is larger. A larger CCD demands a larger lens. That is the difference.

    Furthermore, sensitivity and CCD size may not matter at all! The problem of noise for smaller pixels is only relevant when the camera is capturing lower intensity images. Brighter intensities overcome the noise. Larger aperture lenses also collect more light and resolve better, reducing noise and increasing contrast.
  • by Exocet ( 3998 ) on Sunday April 25, 2004 @05:14PM (#8967395) Homepage Journal
    - The quality of the glass. Apparently some prosumers care about this, see Canon's recent PowerShot Pro1 [] offering. Almost all DSLR owners at the very least *are aware* that glass makes a huge difference - even if they can't afford the best.

    - The quality of the body and mechanicals. No point in getting a nice digicam or DSLR when it's going to break in six months/5,000 images.

    - The camera's firmware. Canon Digital Rebel owners know what I'm talking about. While firmware won't make or break a camera it CAN have a big impact. If the camera doesn't let you do what you need to do, all the glass and megapixels won't mean poop.

    - Many others have mentioned this: egronomics. If you're spending time trying to find the button that lets you do what you need to do then you've missed the shot.

    - Control over the camera. I think this is actually a bigger deal than megapixels or glass. If you don't have the control over the camera that you need, then everything else doesn't matter. This is more of a prosumer concern than a "I just wanna take some pictures"-consumer. However, it does matter. That's why SLR's are popular - people want control.
  • by Fiz Ocelot ( 642698 ) <baelzharon@gmaiF ... m minus language> on Sunday April 25, 2004 @05:14PM (#8967401)
    The same thing happened with CPUs, all people would ever hear about wa MHZ over and over again. AMD even changed marketing tactics to try and show how their CPUs compare to intel cpus, even at lower clock speed.

    Now the same thing has happened with cameras. It's all about megapixels. Your average consumer won't do enough research to learn about how the camera works, all they know is megapixels.

    But what can be done? Instead of producing higher quality optics such as that on the mars rovers(1MP mind you), we get more megapixels with crappy everything else.

  • misleading article (Score:3, Insightful)

    by hak1du ( 761835 ) on Sunday April 25, 2004 @05:20PM (#8967447) Journal
    The images produced from a DSLR are generally deeper, with superior dynamic range, color depth and detail resolved (albeit smaller numerical resolution).

    Right as far as dynamic range and noise are concerned. Wrong as far as "detail resolved" is concerned. A small 8 Mpixel sensor, given sufficient light, will resolve more detail than even the largest 4 Mpixel sensor. Furthermore, in particular for digital SLR sensors, you are better off taking the higher resolution and smaller pixels and removing noise in software than to limit yourself by an otherwise equivalent lower resolution sensor.

    Thankfully, some manufacturers have moved beyond pushing megapixels. Cameras that utilize Foveon's X3 sensor produce smaller images, but they are much sharper, as red, blue and green color channels are captured in every photosite, as opposed to the more standard use of Bayer interpolation.

    ]Foveon's images have not lived up to the hype in tests, and there is no reason to believe that they would. The Foveon sensor really does have 1/4 the spatial resolution of a regular CCD sensor. In return, it avoids some color artifacts and requires a bit less post-processing. But that turns out not to be a very good tradeoff.

    Fujifilm is also taking things up a notch by adding a set of photosites just for the purpose of improving dynamic range with their SuperCCD IV SR sensors.

    That was a nice idea. It's too bad that it makes very little difference in practice.

    Basically, the same kind of people that used to endlessly tout the virtues of film and vinyl records are now out in force making similarly silly arguments about digital cameras.

    Yes, you should remember that higher resolution does not guarantee better quality: a lot of factors need to come together. But high resolution also isn't intrinsically bad and low resolution is no guarantee of lower image noise either. Furthermore, companies like Foveon and Fuji are guilty of using inflated pixel counts to make up for what are actually low actual resolution in their cameras compared to similarly priced models--generally, their cameras are just not good deals.

    If you want to know how well a camera works, the only way to do it is to look at tests and at real images. And within each market segment, both resolution and quality keep going up, and that is no accident.

    And the reason why people want higher resolutions is no accident either: it permits cropping, image processing, big enlargements, and gives people far more flexibility for post-processing. And we can go way beyond 8 or 14 Mpixels before people's thirst for additional resolution will be satisfied.
  • Picture quality (Score:3, Insightful)

    by BCW2 ( 168187 ) on Sunday April 25, 2004 @06:42PM (#8968023) Journal
    and useability are the only things that matter. No one has produced a digital that can come close to my 27 year old Nikon F2, full manual, no auto features. When they do, I'll buy one, but I will not take a step down at the prices a decent digital costs.
  • by Siegecube ( 774438 ) on Sunday April 25, 2004 @06:50PM (#8968067) Homepage
    OK, some basics about (digital) photography from a working professional photographer (not advanced amateur, not EX-professional, not wannabe professional, but a real-life I-pay-all-my-bills-by-taking-pictures professional)

    1. Image quality will be determined by the combination of how many pixels you capture (megapixel count/resolution) and the size of those pixels (sensor size/photosite size), with the weight of the influence going to the photosite size. Thus, resolution being equal between two cameras, the camera with the larger sensor size will give you higher quality captures.

    2. Garbage In, Garbage Out applies to cameras too. This should be obvious. Make sure your lens is able to capture all the data you want to feed to your sensor. If you have a full-frame, 24x36mm 11mp Canon 1Ds (the current professional favorite, myself included), you are wasting it's resolution by putting a cheap lens on it. I've noticed, in fact, that even the highest-quality lenses tend to be unable to deliver enough detail to this stunning sensor, so a cheapo lens is going to f*ck you.

    3. For professional use, film is now dead. Game over. I've done the head-to-head comparisons. I own medium and large-format cameras. I own a high-end drumscanner. I own a large-format printer. I've compared the quality from my previous breadwinning equipment (medium format film scanned by drumscanner) to my current breadwinning equipment (full-frame digital Canon 1Ds) and the digital kicks film ass. That's why it's my current breadwinner.

    Seriously, I had 4x6 foot prints made (notice I said FEET, not INCHES) from drum-scanned 6x7cm transparencies, and from 11mp Canon 1Ds captures, and my own lab couldn't tell the difference. Bye-bye film. And the $10,000 price tag was paid for in film/processing savings before I even got the credit card bill. (for more about how cost affects quality, see below, #5)

    4. The best camera for you is all about what you intend to do with it. A camera is just a tool. Pick the right one for the job. Because of this, most professionals have, on average, more than 3 different camera systems. So, decide what you want the camera for, and the rest of the decisions about it's suitability get easy.

    The most important factor is usually not sheer resolution and image quality. It's about usability of design and ease of handling. If it were all about resolution then most photographers would be using 8x10-inch view cameras. But we realize that a stunning, mega-high-resolution image is useless if the important moment we wanted to capture was missed due to slow camera operation.

    That's why most pros use medium format or 35mm, and most ams use point'n'shoots.

    So, pick a camera that feels good, is understandable to operate, and doesn't get in your way. After these criteria are satisfied THEN you look at resolution/sensor size.

    5. The single most important equation for making better photographs is (forethought x volume of action). In other words, think about what you want to achieve with your images, then shoot as much as you can, and hone your results. This is really where digital capture shifts paradigms. Once you go digital, ANY digital, your visual experiments cost you nothing.

    With film, every time you want to try something new, you are still paying for film and processing (even if you own your own darkroom). This means, effectively, that film and processing are an economic tax on your creative growth.

    So, as long as you stay focused on what you want to achieve (rather then just shooting because you can), buying ANY decent digital camera will yield you better results then sticking with film, and it's use tax.

    Class dismissed.

  • color density (Score:3, Interesting)

    by yulek ( 202118 ) on Sunday April 25, 2004 @08:19PM (#8968568) Homepage Journal
    the reason why i still prefer film over digital (aside from pure aesthetic reasons that are not worth discussing because it's a very personal thing) is the color/tonal resolution. hell, my 2700dpi 35mm film scanner can pick up the grain for some of the films i use, so 6MP cameras already have better "resolution" then what i get with film. however, the scanner struggles in distinguishing between subtle gradations especially toward the shadow end of the spectrum, and the same is even more the case in digital cameras.

    it's not just the number of colors, btw; the average human eye, while amazing, is not going to notice the difference between two shades in a 16bit per channel image (my scanner is capable of 16bit RGB, i don't know of any non-scanning back digital cameras that can do the same) but can the CCD actually resolve those shade gradations to take advantage of all the bits? definitely not the case yet.
  • Marketing run amok. (Score:3, Interesting)

    by Kaboom13 ( 235759 ) <kaboom108 AT bellsouth DOT net> on Sunday April 25, 2004 @10:05PM (#8969075)
    This is what always happens when marketing starts to determine the specs rather then sound engineering. Those who don't do research buy based on the megapixel count and price. This causes a situation where the camera with the highest megapixel sensor crammed into the cheapest possible camera is the most succesful. The same thing happens with everything from printers to processors to cell-phones. The only positive aspect is the informed buyer can sometimes get good deals as a result, as the best camera for the price may not be the most popular one, and stores have to sell it for less of a markup.
  • by Hulkster ( 722642 ) on Sunday April 25, 2004 @10:48PM (#8969271) Homepage
    I'm a BIG fan of digital photography - three issues I haven't seen (quite) mentioned in the Slashdot comments are:

    1. Almost all DSLR's have what is called a focal length multiplier - tends to be 1.3 or 1.5/1.6. This means that your "normal" 28mm lens ends up being a 42mm lens (for 1.5x focal length multiplier) - this has to do with the fact that the CCD chip is not "full-size". This is great for tele shots - i.e. your 300mm lens becomes 450mm ... but really sucks for wide-angle used - i.e. you need a 18mm lens to get a 28mm shot. All point-n-shoot digicams show the 35mm "equivelent", but in actual fact, that is NOT their focal length.

    2. Related to the above is Depth of Field - especially with point-n-shoots, your DOF is much longer, so if you want to shoot a picture that is "tack-sharp" on the subject, but have a blurred foreground/background, that is more difficult - although on the other hand, you do have more DOF if you want that.

    3. Another issue somewhat touched upon briefly is differences in the CCD size between point-n-shoot and DLSR's. With all else equal, the small the size of the imaging pixels, the more noise that can be present, and this tends to go up dramatically if ISO is turned up (first thing I do on a point-n-shoot is turn OFF the auto-ISO and force is to the lowest setting). I'm sure some will disagree, but I'd challange you to print, say a 10X15 print from one of the 8MP digicams compared to a DLSR, both shot in GOOD light (with lowest ISO). Yea, under photoshop, that DSLR shot is just super-silky smooth, but on the 10X15 print, I bet you'd be hard pressed to tell the difference. Having said that, crank up the ISO in your point-n-shoot to say, 800 (yes, even in the newest digicams), and it will look like CRAP - again, at outlined, because the sensor sizes are so darn small, whereas on the DSLR's, you can get away with this (and increase your shutter speed so you don't get motion blur) and the picture may be decent, especially with noise-reducting software/filters applied. From reading Part 1, THIS is the real emphasis of the article.

    I've only scratched the surface here - the article talks about a lot of the above, but most of the Slashdotter's seem to have blown right by this stuff.


    P.S. On those Mars pictures, YES, they were done with a 1MP digicam (with BIG sensors), but just about everything folks have seen is stiched togather, so you are (in some cases), seeing like an "effective" 50+MP shot - welll DUHHH it looks so good!

    • The "focal length" multiplier is a complete misnomer. In reality, a given 35mm lens which is expecting a 35mm piece of film (24mmx36mm) is actually confronted with a smaller detector (e.g. 16mmx24mm), yielding a smaller field of view. Claiming a given lens is magically enhanced by a factor of 1.5 similar to the APS "panorama" format which consists soleley of chopping off the top and bottom of the frame, a feat you could accomplish just as well with a sharp pair of scissors.

      The only way in which a 300mm

  • Cool flower shots (Score:5, Interesting)

    by m.dillon ( 147925 ) on Sunday April 25, 2004 @11:30PM (#8969505) Homepage
    Every time someone posts something about Digital Cameras on SlashDot I usually have enough photos built up to show something new off. So here you go!

    Flower shots from my folks Garden []

    All of these pictures were taken with my Canon-EOS10D, 420EX flash (used mainly for shadow fill), and Sigma 20mm 1:1.8 EX DG prime lens. The shots were taken hand-held in AP mode using F4.0-F16 depending on the conditions. This particular lens produces ultra sharp results at F4.0-F13 or so. The 10D (and 300D) use a 6 MPix low-noise CMOS sensor and you can see it in the above shots.

    Insofar as all the discussion goes, from my point of view it all comes down to three things: Lens Quality, Sensor Quality, and Dynamic Range (of the exposure). SLR's like the 10D have gotten good enough that I don't use film any more. The lens quality is there (being an SLR and taking the same lens as the film EOS's), sensor quality is there, and while dynamic range still needs another 2-4 bits of resolution for my comfort it's still good enough for 99% of the shots I take. Film is dead, digital rendition at 11!

    And I tend to agree with the few other obviously experienced comments (verses the bozo comments from people that don't know jack about taking photographs). You first need to know how to take a picture before you can take a good one. Then comes lens and sensor noise. A lens hood is important, and a good flash (articulated for bounce shots and also be sure to have a diffusor handy) is very important (even when you don't think you need it). For example, most of those flower shots I took were with flash+diffusor, even though it was a bright sunny day outside. The flash was used primarily to fill in some of the shadow (one way to correct for limited dynamic range but it also makes the shots look a lot better).


  • by Junks Jerzey ( 54586 ) on Monday April 26, 2004 @09:25AM (#8971606)
    Megapixels mattered when you couldn't even get a good 5x7 print. Then it still mattered when you couldn't even get a good 8x10 print. At that point they stopped mattering for everyone except professional photographers who need to shoot for ads and posters and so on.

    And of course realize that if you take printing out of the picture and just keep everything digital, then 1 megapixel is fine for 80% of all uses. 2 megapixels covers the rest.

    The huge downside is more megapixels is that, well, the images are huge, so you spend more time tranferring them and backing them up, you get fewer images on a CD, you need larger and more expensive memory cards, etc.

Executive ability is deciding quickly and getting somebody else to do the work. -- John G. Pollard