working distance Bronica SQ-Ai

[romunas]

Does anybody knows flange focal distance of Bronica SQ-Ai? I need to know it for producing monocle for my one.

[Jon Shiu]

I am not sure what you mean, but there is a mark on the side near where the dark slide goes in. It looks like a 0 with a line through it. I believe it marks the focal plane.

Jon

[romunas]

Thank you for answering. But i asked something different. Sorry for my English i'm not very familiar with English

[Bob-D659]

You can measure the distance from that mark to the front of the lens mount yourself, and from a quick google, it should be around 101mm. Info from here

http://www.graphics.cornell.edu/~wes...habetical.html

[Jon Shiu]

Not sure why you couldn't measure it yourself with the info I provided?

Jon

ps not sure what is meant by a monocle?

[Keith H]

.............ps not sure what is meant by a monocle?

Good question Jon, and one I was about to ask.

[MattKing]

Could it be a reference to an eyepiece correction lens - a "diopter"?

This would make sense if by "working distance" romunas meant "effective viewing distance".

[DWThomas]

Hmm - on the SQ series, the chrome ring the lens seats against measures approximately 85 mm from the film plane. With the slight extension of my body cap pinhole adapter, I get a pinhole to film distance of about 90 mm.

But I suspect this may not be the answer to the intended question -- maybe the question is a reference to "eye relief"? Unfortunately, I'm not aware of the answer to that. There are a half dozen different viewfinders, so it might help to know which one, if that has anything to do with the question.

Maybe a quick sketch could bridge the language gap?

[werra]

I guess the idea is to convert the lens to spotting scope, something like http://www.bdimitrov.de/kmp/lenses/a.../monocular.jpg .
From http://www.bdimitrov.de/kmp/lenses/index.html#adapters : "The monocular converter K converts K mount lenses to monoculars. It provides magnification equal to that of a lens with five-times the focal length. For example, a 50mm lens appears to be 250mm and a 300mm lens appears to be 1500 mm."

[romunas]

You can measure the distance from that mark to the front of the lens mount yourself, and from a quick google, it should be around 101mm. Info from here

http://www.graphics.cornell.edu/~wes...habetical.html

101 mm is the distance for Bronica s2a not SQ.
My friend found another site: http://www.geocities.co.jp/Hollywood/1089/mounts.html