Zeiss Ikon, Epson R-D1, Nikon FM3A: same eyepiece/diopter size?

[Mazurka]

Do these camera share the same eyepiece size so that screw-in diopters are interchangeable?

[jlw]

Nobody actually owns a Zeiss Ikon yet; it hasn't been released to the public. Going by the published photos, I'm guessing its eyepiece is considerably larger than the others.

If the FM3A takes the same eyepieces as the FM2n, then it does share the same eyepiece size with the R-D 1. When shopping for Nikon diopters to use on an R-D 1, you've got to buy the newer ones with the non-knurled rim. The older ones with the large, knurled metal rim have the same thread size, but their outer diameter is too large to work on the R-D 1 -- there's a bulge below the eyepiece that interferes with the rim.

[Mazurka]

Thanks for the tip, jlw.

I seem to recall reading somewhere that they do share the same eyepiece size. From the following pictures and using the hot shoes as a rough reference, the Zeiss Ikon and Epson eyepieces seem to have very similar diameters. Whether they are an exact match is another matter, of course.

http://dc.watch.impress.co.jp/cda/static/image/2004/09/30/zeiss106.jpg
http://www.luminous-landscape.com/images-26/rearviewclosedsmall.jpg

[Mazurka]

The Zeiss Ikon does share the same eyepiece with the Bessa R2A/R3A and by extension, the Nikon FM/FE series:

http://www.cosina.co.jp/seihin/co/ikon/sido.html

[ZeissFan]

Interesting how the eyepiece appears screwed on for the RD-1 while it's integrated into the body of the Zeiss Ikon.

[Sean Reid]

Mazurka,

Sure, you're welcome to use my photo of the R-D1

Sean