Lens angle of view question - Speed finder

[jolefler]

I've mounted a Symmar 135/5.6 on my Anni Speed and questions of compatibility with the optical tube finder are arising. It's not a huge deal and it's easy to work around, but....

The images and ground glass view are substancially more inclusive than the optical finder indicates, even with the mask removed. I was under the impression that the finder with mask was set for a 127 to 150mm lens. Are there differences in angle of view for LF lenses of the same focal length?

Again, it's an easy problem to get around, but it sparks my curiosity. Probably a better question for the Graflex site, but there are a number of folks here on both. Thanks in advance for replying.

 

[Jim Jones]

The optical tube finder with a no. 4 mask is intended to cover from 127 to 150mm focal lengths. This mask does not intrude into the tube finder's field of view, but does provide four centering indicators at the edges of the view.