1

Does anyone know if a datasheet is available for the Canon 24-105mm diaphragm unit? I'm wondering if there's a way to use an Arduino or suchlike to control the diaphragm via the flex cable, but I can't find any specs or datasheets anywhere.

Improve this question
3

NB: this answer was written when the question was asking about the shutter, rather than the diaphragm. It may be deleted soon.

There is no shutter in the 24-105; almost every camera system smaller than medium format has a focal plane shutter in the body, rather than a leaf shutter in the lens. The only exception I know of is the Pentax Q system.

Improve this answer
3
  • Really? Huh. What exactly is this, then? youtu.be/WtsW9Hwa4UY?t=121 – Bas Jan 27 '16 at 8:54
  • 3
    That's the diaphragm which controls aperture, not the shutter which controls exposure. – Philip Kendall♦ Jan 27 '16 at 8:55
  • Ugh, brainfreeze. Apologies, I'll reword the question. – Bas Jan 27 '16 at 9:03
2

The best answer I could find to this by googling was a "Pick and Place" blog article where the author describes what he's discovered about the EF-S mount connections:

https://pickandplace.wordpress.com/2011/10/05/canon-ef-s-protocol-and-electronic-follow-focus/

It looks like you send signals on DIN's rising edge (DIN is the middle of the five small contacts), and controlling the diaphragm involves sending the $07$13 opcode, along with a two-digit hexcode value for the specific aperture setting you want. Opening it up to wide open uses the opcode $13$80.

I think. I could be wrong. I just did a quick google. :)

Improve this answer

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.