Accura Focusing Ground Glass ? What does it fit?

[Kino]

Finally digging through my boxes of filters and misc. photo stuff to sort out what is useful and what is not, and I came across this ground glass focusing aid.

Problem is, I really don't know what it fits and internet searches have been unproductive.

Would seem to fit an early 35mm SLR like a Practica or similar with a waist level viewfinder. Anyone know for sure?

It is well built and appears to never have been used.

.

 

[Kino]

DOH! Nevermind.

I turned it over and realized it is for any 35mm camera to check critical focus while the shutter is held open on "B". It has spring loaded ball bearings that clip it into the gate. Actually, its quite nice!

There are several on the 'Bay right now, but the sellers are as clueless as I was moments ago...

 

[AgX]

A bit of thinking.., the cover speaks of focusing and ground glass, thus it hardly can be a finder attachment.
Though a film-rails focusing aid did not come to my mind... maybe if you had given me more time; you solved that enigma a minute after I read your post...

A nice thing.

 

[John Koehrer]

Will it fit the film gate? It would allow GG focus at the film plane.

 

[Kino]

Will it fit the film gate? It would allow GG focus at the film plane.

Yes, that is exactly what it does. Pretty sad I didn't get it immediately...

 

[Kino]

For anyone interested; here it is in action...

 

[AgX]

-) it even is so narrow that it has play to the guide rails. Thus it fits in this point.

-) I guess at the studs are springloaded balls. Will they fit, not harm, all film gates?


When would one use it other than for checking/repairing camera or lens?
I think of critical focusing a plain finder camera.

 

[Kino]

Probably intended for macro work with leaf shutter rangefinders.

It did not seem to interfere with the Minolta SRT shutter, but other cameras might not be so forgiving...

 

[btaylor]

I just ordered one on the ‘bay. It sure beats the kludges I have used in the past, “magic” tape on a piece of glass or bits of old groundglass held onto the rails while trying to hold the loupe at the same time. It’s a quick way to check rangefinder accuracy.

 

[John Koehrer]

I just ordered one on the ‘bay. It sure beats the kludges I have used in the past, “magic” tape on a piece of glass or bits of old groundglass held onto the rails while trying to hold the loupe at the same time. It’s a quick way to check rangefinder accuracy.

Exactly, I used small GG or even Pentax focusing screen but that gadget would have saved a bit of tape.

 

[Kino]

I have since discovered an interesting fact: the Accura GG Focusing Screen depends upon a MINIMUM camera aperture of 35mm x 24mm.

So far I have found that the Petri 2.8 Super Color Corrected (35.33mm x 23.35mm), Petri 1.9 Super Color Corrected (35.32 x 23.43), Petri 7s (35.15 x 23.21) and Fujica V2 (34.95 x 23.44) rangefinder apertures will NOT work with this focusing aid.

However, the Retina IIc (35.00mm x 24.04mm) will accept the device.

I need to measure more cameras, but the trend so far is that Japanese Rangefinders have smaller apertures than one German example.

 

[McFortner]

I just snagged one off of the 'bay just now as well. Should be a big help when I'm adjusting the rangefinder on my FSU cameras.