Basic DIY camera for educational use

bgstcola wrote:

Thanks, looks cool, but it seems like this is more about hacking a mouse (programming, electronics, etc.) that it is about cameras.

The Raspberry Pi is cool as well, but again I feel like it is more about electronics and programming than it is about cameras (the camera is a complete module if i understand correctly) .

I'm looking for a project where the students should spend their time making the optics work so that they can focus the light on the sensor and so on. Maybe that is not even possible to do in a simple way? So it should be mostly a camera project and not too much about electronics.

I did wonder about the intent of the educational project. The trouble with demonstrating the optics of the DIY camera, independently of the sensor, with the projects mentioned is that the image projected onto a ground glass/sheet of paper, or whatever, will be very small and you would need a good magnifying glass in order to make out any details!

The Raspberry Pi camera sensor is a 1/4.0 Sony IMX219PQ and the image-circle is 4.6mm in diameter or 2.6 mm High and 3.68 mm Wide. The sensor used on the iPhone XS (larger than that on the X ) is a not so huge 5.6 mm x 4.2 mm, on a 1/2.5 size sensor.

It sounds like it may be more useful to have a lens that projects a decent size image circle, so that this, when projected, can be seen easily with the naked eye. Medium format lenses from a 6x6 camera will produce an image of 56 x 56 mm which may be about as small as you want to go? There are some inexpensive second hand cameras that might be suitable: Lubitel 166 TLR , the Holga 120N or anything similar as a donor.

Overhead projectors and epidiascopes have useful lenses that will have at least a 200mm image-circle so are capable of use in large-format photography with 4x5 inch images or greater.

This project listed below is rather similar to the system proposed by ProfHankD, except that it uses more expensive photodiodes, rather than LEDs and the self-powered element , of the design is not strictly necessary. They are using a fresnel lens to produce these low resolution 30x40 pixel images.

https://www.vision-systems.com/articles/print/volume-20/issue-7/departments/technology-trends/camera-design-prototype-self-powered-camera-uses-off-the-shelf-components.html

http://www1.cs.columbia.edu/CAVE/publications/pdfs/Nayar_ICCP15.pdf

Finally, a different approach, used by some, is the use of a DIY large-format digital scanning back using a hacked flatbed scanner to produce the images:

https://www.instructables.com/id/DIY-4X5-Camera-Scan-Back/

https://makezine.com/projects/deluxe-scanner-camera/

https://petapixel.com/2014/12/29/medium-format-camera-made-using-parts-epson-scanner/

http://www.stockholmviews.com/diyphotogear/scannercamera.html

Over to you.