DIY Photographer Builds Full-Frame Camera, Open-Sources the Project (dpreview.com) 13
Boston-based engineer and photographer Wenting Zhang built his own full-frame camera and open-sourced the project on GitLab for anyone else to build upon. The camera, named Sitina S1, features a 10MP CCD sensor, custom electronics, and a 3D-printed body. Digital Photography Review reports: Zhang says he started the project in 2017, and it's not finished yet. "Engineers are usually bad at estimating how long things will take. I am probably particularly bad at that. I expected this project to be challenging, so it would take a bit longer, like probably one year. Turned out my estimation was off," he says. He makes clear to point out that this is a hobby project, purely for fun, and that his camera isn't going to achieve the level of image quality found in commercially available products from established companies. Despite that, his project provides a fascinating look into what's involved in building a camera from the ground up.
Although CMOS has become the dominant sensor technology in consumer cameras, owing to factors like speed, lower power consumption and cost, Zhang's camera is built around a 10MP Kodak KAI-11000CM CCD sensor with a global electronic shutter, which he selected for a rather pragmatic reason: it was easy to source. "Most manufacturers (like Sony) aren't going to just sell a sensor to a random hobbyist, so I have to buy whatever is available on eBay. This 10MP CCD turned out to be available," he explains. The choice of sensor has a useful benefit. As he explains in one of his videos, designing and building a mechanical shutter is complicated and beyond his area of expertise, so his DIY design is based on using an electronic shutter. For similar reasons, he chose to use an LCD screen as a viewfinder rather than a prism-based optical design, resulting in a mirrorless camera.
Zhang wanted his design to be compatible with existing lenses. His mirrorless design, with a short flange distance, provided a great deal of flexibility to adapt different lenses to the camera, and he's currently using E-mount with active electrical contacts. And that's just the start. Zhang also needed to integrate a CCD signal processor with an ADC (analog to digital converter), a CPU, battery, an LCD screen and buttons. He also designed and built his own circuit board with a power-only USB port, flash sync terminal, power button and SD card slot, and create the software and user interface to tie it all together. Finally, everything fits inside a 3D-printed enclosure that, to my eye, looks rather attractive.
Although CMOS has become the dominant sensor technology in consumer cameras, owing to factors like speed, lower power consumption and cost, Zhang's camera is built around a 10MP Kodak KAI-11000CM CCD sensor with a global electronic shutter, which he selected for a rather pragmatic reason: it was easy to source. "Most manufacturers (like Sony) aren't going to just sell a sensor to a random hobbyist, so I have to buy whatever is available on eBay. This 10MP CCD turned out to be available," he explains. The choice of sensor has a useful benefit. As he explains in one of his videos, designing and building a mechanical shutter is complicated and beyond his area of expertise, so his DIY design is based on using an electronic shutter. For similar reasons, he chose to use an LCD screen as a viewfinder rather than a prism-based optical design, resulting in a mirrorless camera.
Zhang wanted his design to be compatible with existing lenses. His mirrorless design, with a short flange distance, provided a great deal of flexibility to adapt different lenses to the camera, and he's currently using E-mount with active electrical contacts. And that's just the start. Zhang also needed to integrate a CCD signal processor with an ADC (analog to digital converter), a CPU, battery, an LCD screen and buttons. He also designed and built his own circuit board with a power-only USB port, flash sync terminal, power button and SD card slot, and create the software and user interface to tie it all together. Finally, everything fits inside a 3D-printed enclosure that, to my eye, looks rather attractive.
Full frame camera? (Score:1)
For non-photographers, what is a full frame camera and how does it differ from a regular DSLR camera, or the camera that's built into modern phones?
And why would you want one? What does this get you that the other cameras I listed above don't have?
Re: (Score:3)
> A full frame camera captures the image in one single frame...
This definition is incorrect. Another comment here provides the correct definition and also a link to Wikipedia.
Re: (Score:2)
As others have mentioned, you are 100% wrong on this one. Not even close to being correct.
Re:Full frame camera? (Score:5, Informative)
It's the sensor size [wikipedia.org]
Larger sensors, everything else being equal, tend to be better (resolution, dynamic range, light gathering capability etc). Increased die area costs though. High end dslr's tend to be full frame. Cheaper ones a smaller format with about half the area.
Cameras on phones tend to have tiny sensors because you couldn't fit the appropriate optics for a large one.. and it would dramatically increase the cost of the phone. Most image quality improvements in phones in the last decade have not been from physical improvements but from heavy reliance in computational photography [wikipedia.org] along with some AI to recognize patterns and fudge things to look nicer.
Re: (Score:3)
To add to our post one of the most important factors for full frame is the relationship between focal length and depth of field. Given the larger sensor a comparatively longer focal length is required. How this manifests in pictures is the the longer focal length on the full frame camera (for an equivalent field of view) creates a narrower depth of field which is often a very pleasing result in an image. Smartphones (to your point of computational photography) go to a lot of effort to fake this by applying
Sensor size (Score:3)
"Full frame" means the sensor it the same size as a standard 35mm 135 film frame (24x36mm). With a larger sensor area, individual pixels are larger, so you get lower noise. This improves performance with low light or fast shutter speeds. The main disadvantage is that you need larger lens assemblies.
Re: (Score:3)
The main disadvantage is that you need larger lens assemblies.
Which of course also means increased weight.
Tangent - sometimes full-frame lenses that are considered good but not stellar on a full-frame camera will give great results when used with a smaller sensor (since often the lense's shortcomings manifest more towards the edges).
Re: (Score:2)
The first response to your question is wrong. "A full frame camera captures the image in one single frame ..." is incorrect, as the subsequent respondents pointed out. I am adding a comment thinking you might be interested in why there is a distinction. Going from film to digital, over a roughly 20 year period 1995 - 2015, meant developing the technologies - and that was not trivial. Various low quality cameras came out, but for the top tier camera makers like Nikon, Canon, Sony, Minolta, etc., the came
Vignette like from the early steam age. (Score:2)
But nice nonetheless. It has a decent body for such a project which is also good. However, the photography thing itself does need work before it's viable and quality is up to modern standards. But being open source perhaps some others will pitch in and help.
Overall a neat hardware project. Extra brownie-points for trying this and seeing the first iteration through IMHO.
Re: (Score:2)
I believe some people think CCD create better images, but is that still the case?
"Better" is a word that is doing a lot of heavy lifting. There are a lot of different ways in which to describe image quality. CMOS is objectively better in some areas: it's far easier to create higher resolution sensors, it consumes lower power (which funny enough leads to an interesting point about noise, CCD is usually cited as the lower-noise option all else being equal, but localised sensor heating raises the noise of the sensor meaning CMOS actually may produce the lower noise). There's also some very