07-16-2020, 07:54 PM
Sorry BC, I can go overboard with the abbreviations, and it wasn't even necessary. People use different terms, but I meant Flange to Focal plane Distance. Normally you can't adapt a mirrorless lens to a DSLR because to have the same FFD there would not be room for the rearmost elements. The F/11 lenses (from the drawing you linked to earlier) don't seem to have glass in them. I am pretty sure I've never seen a rangefinder, or mirrorless lens that could be made significantly shorter just by shortening the end of the lens.
FFD's concerned are EF is 44mm, RF is 20mm so the RF F/11 lens would have to shortened (extended less) by 24mm. Amazingly this is not optically a big issue. Of course Canon would have to provide the EF mount, and shorten the tube.
And who knows if it would even work. Possibly shortening the tube would shorten be focal length at least a little. But if it worked, I might finally get closes enough to the very high nests of some of the Herons, and Hawks that nest very high up in trees, or get photos of birds on rocks that are a ways away from the cliffs on the shore near where I live. I could endure Live View to get to do that!
FFD's concerned are EF is 44mm, RF is 20mm so the RF F/11 lens would have to shortened (extended less) by 24mm. Amazingly this is not optically a big issue. Of course Canon would have to provide the EF mount, and shorten the tube.
And who knows if it would even work. Possibly shortening the tube would shorten be focal length at least a little. But if it worked, I might finally get closes enough to the very high nests of some of the Herons, and Hawks that nest very high up in trees, or get photos of birds on rocks that are a ways away from the cliffs on the shore near where I live. I could endure Live View to get to do that!