Zeiss Ikon 427 finder

[laptoprob]

Recently I got this strange finder. I wanted it because the full fov. just might be suitable for 25mm and it appears to be so.
It is a multi-frame brightline finder. 35 and 85 are indicated, in between must be 50 and beyond is 135. The latter is too small for proper usability I think.
Here are some pics showing the finder on my Leica IIf and side-by-side to the Russar 20mm finder.

 

[laptoprob]

images

images

And here what it's all about: What do the finders show.
Well, the 427 is kinda cluttered with all the framelines. Coloured greenish and darker because of the mirror system. Magnification around 0,4 I think. Barrel distortion is definetly noticeable.
The Russar is fantastically bright. Magnification around 0,5. Barrel distortion hardly noticeable. And wider than 25mm ofcourse.

 

[peter_n]

The 20mm Russar finder is an amazing bit of engineering, with mechanical parallax correction built in too!

 

[micromontenegro]

The full field of the 426 and 427 finders is for the 21mm Biogon

 

[laptoprob]

Well, that's what I've seen reported as well, but the full field compares very well to what my 25mm actually projects.