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Media Technology

Beyond Megapixels - Part III 231

Posted by timothy
from the you-must-mean-gigapixels dept.
TheTechLounge writes "Beyond Megapixels - Part I & Part II have both been posted here at Slashdot, and now it is my pleasure to bring to you Beyond Megapixels - Part III. This is the final part of this series of editorial articles examining current digital photography hardware. In this segment I will be focusing on function, filetypes, and features."
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Beyond Megapixels - Part III

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  • ...purchases in the last few months and I have to say that the "megapixel race" is becoming like the megahertz race in that many people use that feature alone as their determining factor. Rarely do they want to discuss optical versus digital zoom (something that Kodak is addressing with their DX6490, a 10X OPTICAL zoom in an inexpensive, well-built camera), output format, etc.
    • by FraggedSquid (737869) on Wednesday June 16, 2004 @08:11AM (#9440447)
      I remember watching a review of digital cameras on a gadget show a year or so ago. The reviewer pointed out that the key to the image was the lens, if that is bad, then nothing else matters.

      Don't talk pixels, talk optics.
    • Sigh. Zoomfactor is just as much a non-informative factor as megapixels.

      10x what? 28mm (equiv)? 35mm? 38?

      That's quite a difference. And the wide angle is more important than the zoomfactor anyway, in 9 out of 10 cases.
    • Jacksonville BBS Scene? In the 80s-90s


  • The other two: (Score:5, Informative)

    by cablepokerface (718716) on Wednesday June 16, 2004 @08:08AM (#9440438)
    For the RTFA-ers:
    Beyond Megapixels [slashdot.org]
    Beyond Megapixels - Part II [slashdot.org]
  • Linux and RAW. (Score:5, Informative)

    by caluml (551744) <slashdot@nOsPAM.spamgoeshere.calum.org> on Wednesday June 16, 2004 @08:10AM (#9440442) Homepage
    Linux users can use the dcraw [cybercom.net] util to convert RAW into TIFF format. It also has a plugin for GIMP which works fine. On my camera though, the RAW files are 6.3Mb, and the TIFFs created with dcraw are 18Mb.

    Have a look at my pics [umtstrial.co.uk], too. :)
    • Re:Linux and RAW. (Score:5, Insightful)

      by afidel (530433) on Wednesday June 16, 2004 @08:15AM (#9440476)
      Yeah but when you convert you lose the ability to do all of the advanced image manipulation stuff based on sensor information. There are tons of different transforms that work MUCH better if they have the info directly from the sensors rather than a pixel value extrapolated from those values. Personally I think I would run Photoshop and my camera vendors RAW utilities under xover office before just dumping the data to TIFF, otherwise why not just use superfine JPEG?
      • Re:Linux and RAW. (Score:2, Informative)

        by ookaze (227977)
        If you read the DCRaw story and homepage, you would see that the Photoshop CS plugin using at least part of dcraw, but, most importantly, that dcraw produces better results than the proprietary converter softs (see the links on the homepage).

        The cool thing about the RAW format is that you can then apply all the transforms the camera is doing, but with a more powerful computer, meaning you use, hopefully, more powerful, but more demanding algorithms. You can still refer to your camera to get the actual sett
    • Readers may also be interested in Free Software for the Nikon D70 [fsck.org.uk].
    • ICC color profiles (Score:5, Interesting)

      by Speare (84249) on Wednesday June 16, 2004 @10:01AM (#9441386) Homepage Journal
      The huge missing-feature for working with RAW images on Linux is not how to read the files, but how to manage color. ICC profiles are a critical part of the process to go from sensor to screen to printer without major swings in color fidelity.
      • sensor * sensorprofile = calibrated image

        calibrated image * deviceprofile = output

      High-end cameras can attach or apply various sensor profile transforms to the actual sensor data, leaving the pixels in a factory-average sRGB, such as AdobeRGB colorspace. Some can even apply or attach custom tone curves or custom colorspaces if you put the profiles on the memory card.

      I haven't used Sane in a while, but it would also need a sensor profile capability.

      Since the 2.0 release of GIMP, it has been making small steps leading up to support for attaching color profiles, but not actually applying color profiles.

      I've heard that some people on the Xorg team have been considering the full scope of solutions for this problem, but I would rather they just hit the 90% mark with one feature: load an ICC display profile and program a single head on the video card to apply that transform for all X output on that head. Let's not wait for the whole thing (how to profile, how to work multihead, how to manage multiple profiles, etc.) to spring out of the head of Zeus.

      CUPS or some other printing subsystem should be able to take ICC printer profiles also, and prefix printer jobs with those profile transforms where appropriate.

      Then you'll see a LOT of people in the photography world erase their Windows and their Photoshop, and join the marketplace vote against product activation.

    • I just did a digicam presentation for my LUG and included info on dcraw. There is also VueScan which allows more complex RAW manipulation, though the UI is a bit wacky. Cross platform non-free software, but it works well, and deals with scanners, files, etc.
  • Beyond megapixels (Score:5, Informative)

    by Ianoo (711633) on Wednesday June 16, 2004 @08:13AM (#9440463) Journal
    I think the general sentiment of this article is very true. I remember when I bought my first digital camera, it was a case of the biggest number of pixels winning. In those days 1.0MP cameras were pretty expensive, and I remember being overjoyed that I managed to get a great deal on a Kodak that reached this "magic figure" producing 1152x864 images - rather than most of the other cameras within my price bracket at the time which were between 640x480 and 1024x768.

    Skip forward to last month, and I bought my third digital camera. There were 3MP, 4MP and 5MP models within my price range, but in the end, I settled for a 4MP model with a great lens, full manual control and some nifty other features (a Canon Powershot A80, I'd recommend this model to anyone after a fortnight of snapping with it). It produces 2272x1704 images, quite a lot bigger than I'm ever likely to need.
  • Why Megapixels? (Score:5, Interesting)

    by KlausBreuer (105581) on Wednesday June 16, 2004 @08:16AM (#9440481) Homepage
    Well, you do need a certain minimum of megapixels, so you can have your photo printed. See, I never print photos on my PC (which is why I don't need an inkjet* with highly expensive ink (1 liter = 1 kg Gold)), but bring or send them to the photoshop instead.
    They will print it using a seriously good printer on great paper, and charge a pittance for it. Some shops (and websites) also allow me to design a nice hardcover book full of my photos and text, which makes a great present for friends and family.

    But the requirement-limit is at, what, between 3 and 5 megapixels. Using more is useful for cutting images and having only a small part printed, but this happens rather rarely.

    Instead I want the following:

    * a good optical lens (come on, an f of 2.8 is not that great, unless you live in a really sunny country) with a solid optical zoom (who CARES about digital zoom?).

    * Use standard AA rechargable batteries - they are cheap, hold a heck of a charge by now, and are easily replacable - with plain batteries if necessary.
    Keep in mind that these things have to be replaced every now and then, and a propriatary one isn't cheap.

    * Use CF cards. Cheap, fast, big, and under steady development.

    * Allow me to access the camera via USB as an external drive, without needing some kind of stupid program.

    * Reasonably small, so I will usually carry it with me in my pocket instead of leaving it at home due to bulk/weight.

    Currently, I use the Canon A70/A75/A80. I can recommend them all, except for the lens (2.8, but this currently is standard, except for the great Olympus 5050 with 1.8), and the interface (I have to pop out the CF to read it - I'm not using some kiddy-aimed windows program here).
    Not too expensive, either (nope, I have no connection to the manufacturer).


    * Tip: Buy a used postscripting laserprinter with >= 600 dpi. Dirt cheap, toner lasts forever, you'll love it. And no drivers needed, ever.
    • come on, an f of 2.8 is not that great, unless you live in a really sunny country

      Actually, 2.8 is fine on a camera that gives acceptable quality at ISO 400. The lens I use most on my Canon D30 is a Tamron 28-75 f/2.8 and it's fine for available-light shooting indoors. In fact I don't recall when I last used the flash on that camera. Outdoors I drop to ISO 100 or 200.
    • Re:Why Megapixels? (Score:5, Insightful)

      by StateOfTheUnion (762194) on Wednesday June 16, 2004 @09:21AM (#9441008) Homepage
      * a good optical lens (come on, an f of 2.8 is not that great, unless you live in a really sunny country) with a solid optical zoom (who CARES about digital zoom?).

      There's a lot more to a lens than the F-stop . . . 2.8 is pretty darn good in a lot of the pro-lense market for SLR's. Getting larger aperatures than this often causes significant distortion in the lens . . . hence the super-expensive cost of the really fast lens, or in the case of a lot of consumer level digital cameras, crummy optics that result in a loss of sharpness . . . this is going the way of the megapixel wars . . . uninformed consumers think that larger aperature and bigger zoom = better camera . . . typically the truth is larger aperature and bigger zoom = crappier overall sharpness and more lens distortion . . . which amounts to crappy looking pictures.

      Personally, I'll take my Nikon Coolpix 5000 with its slower lens (3.3) over just about any faster lens consumer digital camera any day . . . I know that the optics aren't perfect, I bought it 4 years ago, but even by today's standards, the optics are a lot better than most consumer digi-cams I've seen. And I'll take my Digital SLR over that . . . any day.

    • Even if you are not going to print your digital photos, there is still one reason you might want the highest pixel count:

      zooming in on the details.
      • The problem is that the sensors are not all alike. The Sony F828 has a lot of pixels but also more than just the RGB filters (adds cyan). Normal cameras just have RGB filters. Fuji rotates the sensor a bit and offers sensors with higher dynamic range. The Foveon chip stacks sensors so a 3.4 MP camera has 10 million image sensors, and an image quality somewhere in-between 3.4MP and 10MP as a result.

        In short, relying on just the MP count is not really going to help anymore, especially now that companies
      • Re:I'll tell you why (Score:5, Informative)

        by joebok (457904) on Wednesday June 16, 2004 @11:08AM (#9442087) Homepage Journal
        Part of the articles intent was to make a distinction between the "quality" of pixels - 8 megapixels on a small sensor (top-end "prosumer") will likely have more noise than 6 megapixels on a larger sensor (digital SLR) so that when you are viewing the images 1-1 the details can still be better with a lower pixel count.

        There is also the matter of the Foveon "X3" chip - it's got only about 3.5 megapixels but each pixel records the red, green, and blue coming to it rather than the traditional sensors that will only record one of the colors (the final image is then an interpolation). The manufacturers say this is equivalent to 11 megapixels, but I don't think it's quite that good - certainly comparable to 6 to 8 however.
    • 1. Digital zoom is sometimes useful - treat it as "lossless cropping" when you shoot JPEG.

      2. These Canon cameras use PTP. Doesn't act as a USB drive, but isn't proprietary either. Gphoto can read from them. No need to get a CF reader.
      • No need to get a CF reader.

        Actually, I preferr to use the CF -> PCMCIA adapter for reading CF cards. I have a 256M card I keep in my digital camera, and often never empty it, I'll keep the pictures on the card so that I never forget. And while there are some nice USB2 card readers out there, PCMCIA's bus speed (which doesn't even compare versus Cardbus, and I don't recall the USB2.0 speeds) is far, far superior than my laptop's USB1.0 speed.

        Downloading 200M of images, takes quite a bit over USB,
    • Re:Why Megapixels? (Score:3, Informative)

      by archeopterix (594938) *

      See, I never print photos on my PC (which is why I don't need an inkjet* with highly expensive ink (1 liter = 1 kg Gold)), but bring or send them to the photoshop instead.

      The ink is only that expensive if you buy the original cartridges from your printer manufacturer. The printer manufacturers strive to make their cartridges incompatible with everything else, but for most ink printers you can get a decent continuous flow system. This way you buy only ink, which costs an order of magnitude less per liter th

  • Previous Stories (Score:5, Informative)

    by Roofus (15591) on Wednesday June 16, 2004 @08:21AM (#9440516) Homepage
    Since I haven't read them, and I don't see them posted here anywhere, here are the links to the first two stories:

    http://www.thetechlounge.com/article.php?directory =beyond_megapixels_part_1 [thetechlounge.com]

    http://www.thetechlounge.com/article.php?directory =beyond_megapixels_part_2 [thetechlounge.com]

    Ah yes, I can feel the Slashdotting coming on now =)
  • by fdiskne1 (219834) on Wednesday June 16, 2004 @08:25AM (#9440529)

    I am what you would consider a serious amatuer photographer. (Note that's not seriously amatuer.) I like taking nice photos and blowing them up/enlarging the best of them to frame and hang on the wall. I've even had one professional gig where I got paid for taking official photos at a wedding. A few extra bucks for me and some decent photos at a cheap price for the couple.

    Here is my perfect camera:

    1. Six Megapixel. You can print out an 8X10" photo at the same quality as 35mm film. More is better, but does an amatuer really need any more than that?

    2. An SLR. This is a single lens reflex. It focuses the image onto the focusing screens by using the light coming through the lens (what you see through the view-finder is what you get) and has interchangable lenses.

    3. Has a nice optical zoom. How many X makes a nice optical zoom? I suppose that's up to the individual, but I think 10X or more. More is always better when it comes to optical zoom.

    The Canon Digital Rebel seems to be the perfect camera for me. The price is still a bit out there, in the neighborhood of $1000, but I'm sure it will come down as time goes on. I'm thinking we are nearing the end of the major advances in digital cameras. Not that we can't improve them, but they are practically at the quality/price levels of film cameras. You can get a cheapie for less than $100 that takes "okay" 3 megapixel images. Great for 4x6 snapshots. You can also spend about $1000 for everything a non-professional could want. Any improvements beyond this are gravy and probably wouldn't profit the researcher or manufacturer much.

    Oh! And ignore digital zoom. I wish it didn't exist. I can enlarge it on my computer after the fact and get the same effect.

    • Six Megapixel. You can print out an 8X10" photo at the same quality as 35mm film.

      In the past six years, I have ordered a print at that size only twice. And they were pretty blurry (taken with a mid-range compact camera) if you look at them from close by (what I usually don't do with pictures that hang on the wall).

      An expensive camera does not give you good pictures if you don't know how to create a good composition.

      Has a nice optical zoom. [...] I think 10X or more.

      I hardly ever zoom in all the wa

    • Oh! And ignore digital zoom. I wish it didn't exist. I can enlarge it on my computer after the fact and get the same effect.

      Not quite. The photometry of the photo will be based on the entire picture. If you take an un-zoomed picture and then crop it, the photometry will be off. Probably not by much, but it's still off. Digital zoom at least allows the camera to choose the correct settings for the image you have framed.

    • by Zog The Undeniable (632031) on Wednesday June 16, 2004 @08:49AM (#9440722)
      Don't good LCD viewfinders make SLRs redundant for digital cameras? There really isn't much point in having all that moving-mirror hardware; if you must have a bigger image for focusing, electronic viewfinders are available. I speak as someone who also uses a medium format SLR, by the way.
      • You'd need a very high quality electronic viewfinder to match the quality of the image as seen through an SLR. LCDs also drain far more power from your batteries than an optical system. The mirror also serves to help keep dust off the CCD whilst changing lenses, although this could be worked around.
      • by Agent Green (231202) * on Wednesday June 16, 2004 @09:08AM (#9440904)
        Firstly, there are no good LCD viewfinders...especially when we're talking about still frame quality of any kind. Secondly, there is no need for an SLR mechanism on a digital LCD viewfinder, since the picture is being fed from the imaging CCD anyways. Cameras such as the Canon D300, 10D or any other digital SLR don't use LCD viewfinders, because that's not what their customers really want or need...and it would defeat the purpose anyway.

        When I was in the camera market, I was going for either the Digital Rebel or the gigantic Sony 8MP thing...and eventually settled on the rebel. (Okay, its was the EF Lens capability that won me over). I find that being able to make image adjustments is a lot easier when I'm looking at exactly what will be photographed, instead of some downsized representation. That, and I take good pictures from anywhere in the ballpark with an additional zoom lens. :) More or less, I can do more serious amateur photography without spending my entire livelihood on film/development/printing, which allows me to take many, many more pictures.

        Granted, this works because I bought my camera to be a camera...not some kind of camcorder...which is one feature most LCD viewfinder cameras offer.
    • More is always better when it comes to optical zoom.

      Any lens that has more than 3x optical zoom will be making some heavy compromises to do so. You're up against the laws of physics here, if you want to fit such a lens into a portable package. You really would be much better off carrying several lenses (that's what SLRs are for) or two bodies with a different lens on each.

      Canon makes a 28-300 lens for people who absolutely cannot change lenses in the field (for example, photojournalists in the middle of
    • An SLR

      In the digital world, if it's not an optical viewer then the image is being taken from the sensor, so "SLR" is irrelevant: what you see is what you get on all digital viewers -- they're using the imaging sensor.

      10X or more

      You're talking about going out to, say, 350mm. Good luck hand-holding that sucker.

      I note you don't mention anything about dynamic range of different sensors, charge leakage to adjacent cells, white balance limitations, pincushion & barrel distortion and so on. You shouldn't b

      • In the digital world, if it's not an optical viewer then the image is being taken from the sensor, so "SLR" is irrelevant: what you see is what you get on all digital viewers -- they're using the imaging sensor.

        That's true and not a problem when everything is still. However if you're either panning the camera around to catch something or the action is fast, how quickly the viewfinder responds become an issue. Also, with an SLR you don't burn any power running the viewfinder.
    • My coowore picked up that camera for closer to 700

      (since he had lenses for canon - no lens.

      That puts the digital SLR surprising close to the high end consumer stock.

      Very appealling.

    • I'm thinking we are nearing the end of the major advances in digital cameras. Not that we can't improve them, but they are practically at the quality/price levels of film cameras.

      Not so sure. For a long time I was convinced I'd get whichever Canon digital SLR dropped below a grand, to use with my set of old EOS lenses preferably. But you know, there's a huge difference in size from the Sony snappy we've picked up in the meantime and an SLR body. There are limits to what one can do with glass, but I'm go

    • Unless you need to print really big prints all the time, another good choice is the Canon PowerShot S1 IS.

      Despite the fact it's limited to 3.2 megapixels in resolution (which means you can still print 8" x 10" pretty clearly with a good-quality printer), the PowerShot S1 IS has one thing that many people ignore: a decent lens system. With its true 10x optical zoom, this camera can zoom the lens at very high levels with very little optical distortion caused by the lens.
  • The article glazes over everything and provides less information then a product pamplet . . . unless you don't know anything about digital cameras, haven't seen a digital camera, have never touched a digital camera, never read about a digital camera, and you've been living under a rock, I wouldn't bother reading this article.

    In all seriousness, the really odd bit about this article is that the author doesn't seem to know his audience . . . he writes about the most basic of features at a very high level fo

    • > The article glazes over everything and provides less information then a product pamplet . . . unless you don't know anything about digital cameras, haven't seen a digital camera, have never touched a digital camera, never read about a digital camera, and you've been living under a rock, I wouldn't bother reading this article.

      Amen. From the article:
      "There are two major factors that characterize a good focusing system: speed and accuracy."


      I'd like to know what he means by "accurate". My fir

  • That's all? (Score:4, Interesting)

    by baxissimo (135512) on Wednesday June 16, 2004 @09:37AM (#9441151)
    I found this series to be a pretty big let down. I guess I was expecting too much, but I was hoping the author would go down the list of where digital doesn't live up to film as a call to action for camera makers and consumers. But no, the series for the most part just talks about existing digital camera features like autofocus and zoom lenses. Oh well.

    I want to see some serious discussion about things like color gamut. The gamut of film (especially slide film) is much better than that of digital cameras. Is anyone working to improve the situation for digicams? There's a interesting looking article at extreme tech that talks about gamuts here [extremetech.com].

    Basically current sRGB devices don't cover the full range of colors which the human visual system can percieve (nor does film, but film comes closer than digital). Think of deep violet for instance. You simply can't get those hues on a monitor, and so today's digital cameras just don't record those colors. However, it is likely that some day we will have monitors and hardcopy ouptut devices that perform as well as the human visual system. So ideally the pictures I take today would have the full range of color information, even if they're forced to display only a subset of those colors on current display devices. That way, in the future when "uberdisplays" are available, my pictures from 2000 will still look nice, and not washed out and cheesy like color photographs from the 60's do today.

    If you widen the gamut of CCDs, you'll probably want to add a few bits to each color channel as well -- use 12 bit color instead of 8 bit for instance.

    And as long as you're adding bits, the other thing it seems like digital cameras could possibly offer some day is point-and-click high dynamic range (HDR) images, say in EXR [openexr.com] format. Couldn't one build CDD sensors with automatic gain control (ISO) on a per-pixel basis, and then assemble the results into a HDR image? Currently the way to make HDR images is by taking several photos of the same scene and carefully merging them together, but that's pretty cumbersome.

    With HDR images, you have much more flexibility to adjust the exposure and reveal detail in the shadows after taking the image.

    What other cool things could digital cameras offer that would take us beyond simply replacing film cameras?
    • First of all, a number of cameras (especially higher end cameras) let you choose the Adobe RGB color space, which while not matching human vision is better than sRGB. Also, since a lot of people are just going to be displaying for the web sRGB may be all they ever need - and since the printer range is stuck around the same area as Adobe RGB I'm not sure what benefit you'd get from a much higher range since no output device could support it.

      As for the higher dynamic range, the Fuji SuperCCD does something
  • Only DSLR's and some Nikons do that.

    I've been shooting digital for a few years, and 4:3 STILL look ugly to me.

    Please, add 3:2 outputs.
    • Actually some Olympus do as well (my gf's C-4000 for example).

      (who is currently researching and trying to narrow things down between Canon and Olympus, while simultaneously arguing with myself about budget)
  • Flash Capabilities (Score:3, Insightful)

    by BenEnglishAtHome (449670) on Wednesday June 16, 2004 @09:52AM (#9441298)
    Other than a brief mention of "virtual fill flash" from Nikon, I don't see anything in any of these articles about flash capabilities. I don't care about the built-in flash, but having an external, powerful, fully integrated flash unit sitting a foot above my lens, held by a high-quality bracket, is extremely important to me. My Nikon F5 is almost never used without the SB28 flash unit (I tend to shoot people, indoors) and the combination is *SO* much more than the sum of the parts.

    So here's my question and one of my big selection criteria: What non-interchangeable lens digital cameras are available with highly integrated and powerful external flash systems? All the usual requirement of a good lens, etc., also apply. Anybody have any experience/knowledge to share?
  • Its all child's play compared to 4x5 large-format photography. I think it will be a long time before they are able to manufacture a 4x5" CCD or CMOS sensor economically. If they do, well then it will probably slide into the back of my view camera like sheet film, polaroid holders, and roll-film holders.

    However the right digitoy makes a nice light meter.
  • Needs (Score:2, Informative)

    by ericlp (749865)
    As mentioned, it is all in what you need it for. Many of today's consumer digital cameras are nothing less than outstanding. If you have had to suffer through the growth of digital cameras like I have ( $20-25,000 ) DCS1 Camera circa 1992 ( 1.5 megapixel approx ) and lousy color and contrast ) All you pukes :) should be thankful today.

    Pros will always need large megapixel cameras. Example: Group shots, even then the industry is still working out bugs. The Kodak DCS n14 ( 13.5 megapixel camera )is aweso

"I may kid around about drugs, but really, I take them seriously." - Doctor Graper