Rear cap size for the 90mm SA

[Carography]

I just aquired a 90mm Super angulon. The front is a snap on 67mm.
What size cap am I looking for on the rear? I dont think a snap on will work very well. Probable need a slip on type.
Any info help full
Here's a photo of the lens.

[Per Madsen]

It is a 57 mm rear cap on mine (Super Angulon with Compur 00 from 1961).

[Steven Ruttenberg]

My Schneider SA 90mm f5.6 I just purchased is huge. 82 mm front filter thread and rear looks to be as big.

[Randy]

Guessing the f/5.6 is substantially larger the the f/8. My f/8 feels like it's made out of plastic - so light.

[Luis-F-S]

Did you try measuring it? That's what I'd do. Trace the outline of the lens and the measure what you traced. L

[Jerry Bodine]

I put the calipers to my 90 f/8 SA lens that has factory slip-on caps to measure the barrel OD sizes; front is 70mm, rear is 57mm.

[Bob Salomon]

I put the calipers to my 90 f/8 SA lens that has factory slip-on caps to measure the barrel OD sizes; front is 70mm, rear is 57mm.

Don’t those caps have the size molded inside in the center?

[B.S.Kumar]

Don’t those caps have the size molded inside in the center?

No, Schneider caps have an undecipherable code. Fuji caps have the size molded inside.

Kumar

[Mark Sampson]

Once upon a time, you could visit your local camera store and rummage through a drawer full of random lens caps until you find one the right size. Kinda miss those days- most of my lens caps are non-original and came from such sources.