To breaking the limits of original 110A/B front standard, to mount bigger size lens/shutter, I did try many ways to expand its ability, from beginning the target was to accept #0 shutter only, then by add additional spacer ring, now Byron accepts #1 shutter too, but due to the 'bottle neck' that spacer ring brings, some lens with big rear element is limited.
Lens board study
150 Lens mount study
#2 shutter (Yes! #2 shutter, not #3!!), I had to re-design whole front standard to take it. But at least initial test showed it is possible! see here:
Project I'm possible
The nearest distance Xenotar can get
Now, for a easier way to mount/un-mount this big eye, I need to develop another front standard/ lens board system, differ from the previous version.
They will be similar to normal view camera, with a somewhat rectangular lens board, and front standard will have a spring clip to lock the board.
The board, with maximun size of open hole to 60mm, Byron surely expands its lenses option, and since front standard extrudes a little bit, avoiding struts conflicting with shutter, so #2 shutter is possible too.
75mm lens on Byron
With new design, it may be no problem any more, but I need test first.
New system is specifically designed for big size lenses, it may not allow lens to stay in camera body when folded. I will try to keep the lens in, if lens board reverse the direction.
Oh, another minor thing, bellows needs new size too, for those big rear...
I got a Grandagon 4.5/75mm lens in #0 shutter, the one shown in image above, a beauty.
New front standard/ lens board system plans to take this lens as wide angle end limit, not because front standard extruding or backward some distance, to avoid the blocking of camera bed, but by rising the lens a little bit.
The only chance to avoid the blocking, is to rise the lens.
I checked Grandagon data, it has 195mm image circle in f22, so there is plenty area to move.
Another way to solve the problem is by rising the lens a bit, makes less blocking area, thus eliminates the shading in negative area.
This way works in two conditions, 1. lens image circle is big enough for rising. 2. lens rises enough distance.
195mm image circle is big enough for rising, the only problem is how high can we rise the lens?
But again, I need the test to approve it.
And why 61mm in dia. opening? Well, I want to directly mount the lens, and Grandagon 75 has a 60mm dia. rear, that is why.
(16/05 add)Just back from factory, lens board spring clip parts are so small, and complicated, very difficult to assembly, and I don't like the effect, need to find a simpler way to hold the board......
(18/05 add....)Had reduced spring clip into one part only, with spring(s), and bolts.
(To be continued..)