12mm and 15mm Heliars on F3/F4/F5?

[L. M. Tu]

Talking about F-mount Heliars, will they clear those bodies? I think VC mentioned only the F and F2 and some of the Nikkormat models, but I think those lenses might fit in later F-series cameras. Am I right?

 

[jaredangle]

The mirror has to be locked up, and an external viewfinder used for framing. AFAIK the mirror on an F3/F4/F5 cannot be locked up.

F4 has a full-time mechanical lockup level attached to the DOF preview button, and the F3 has the exact same assembly as well. So I believe the Heliars would work for the F3/F4, but I'm not sure as to whether or not it would hit anything else inside the camera body.

 

[Bob W]

The F5 also has a lever to lock up the mirror. The only single digit F not to have one is the F6 I think.

Bob W

 

[L. M. Tu]

Yes, the F6 is the only body with no mirror lockup, unfortunately.