I started working on a firmware for a DIY SLR film camera that will use also Canon EOS lenses. I'm using the Nucleo L152RE board equipped with a low power STM32 microcontroller (currently, learning how to use it's peripherals - but not first time microcontroller programmer). I will use the TSL2591 light sensor and for this, I will port the Adafruit Arduino libraries to C language. For the shutter, hopefully, I will get an EOS 6D shutter and start playing with it, but a mechanical shutter is also possible. For the EOS lens protocol, Magic Lantern forums were a valuable source of informations. If someone have the Canon EOS 6D shutter protocol (how is armed and released), and maybe a schematic with also voltages involved, will be much appreciated. The general idea is, film cameras are getting old and very old, the ones that are still manufactured (Leica and Nikon) are immensely expensive. So, there must be a DIY design for anybody to make, assuring the film continuous existence. Reusing parts from old cameras with old technology is not a long term solution so, it must be something that you can acquire from today's market. And in my opinion, Canon EOS lenses have the best digital interface ever. The electromechanical shutter can be also from other brands, but going with Canon will be great. I can think of the firmware functionality but I'm not very good with the mechanical part and also not yet having a CNC router that would help me make some parts... it will be a long term project for me, no time frames imposed.