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View Full Version : "Swapped" shuttered lenses, where to get calibrated/zero'd and new scales made?



Daniel Stone
27-Jan-2013, 16:56
Thought that this might be something others might get some use out of, and I can gain some info I need as well for my current situation.

So my case:
I purchased a Fujinon-A 300mm this morning from a Japanese dealer on ebay, but the shutter has been swapped from another lens. Sale here:

http://www.ebay.com/itm/FUJI-FUJINON-A-300mm-f-9-in-Copal-No-1-Shutter-is-not-original-/251220216922?ssPageName=ADME%3AX%3ARTQ%3AUS%3A1123&nma=true&si=uYV7RsSHUWxkeH0JYt4N3p3wbdY%253D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557

Think this lens needs to get 'checked' for cell spacing and all that, so its back to factory specs for best performance for the shutter its now mounted in? Also, need to get an aperture scale made, sources(besides SK Grimes)?

thx,
Dan

Dan Fromm
27-Jan-2013, 17:34
Dan, people will jump on me for suggesting that if it fits a #1 at all then the cell spacing will be ok. Watch out, here comes Leigh, followed closely by Bob Salomon. But that's usually the case. The tolerances aren't that loose and it is a relatively long lens so the error, in % of focal length, will be small.

As for the aperture scale, well if you're going to use it the one that's there will do just fine. Here's the trick: open the diaphragm wide. Hold the lens at arms' length, put a ruler across the front. If the exit pupil's diameter is 33.3 mm -- it should be, the shutter's maximum is 30 mm but the front cell should magnify the aperture some -- then slowly close the diaphragm until the blades just appear. Open up until the blades just disappear. Iterate a few times. The pointer's position on the scale will be f/9. The scale is marked in 1/3 stop intervals. Count down from f/9 to the aperture you want ...

If you have resale in mind, then having the scale replaced would be a good idea. If you can find Fuji, asking them if they'll sell you a scale is worth a try.

Yours for solidarity among Dans,

Dan

Louis Pacilla
27-Jan-2013, 17:48
You may be able to purchase the correct scale set for the 300 A -Copal 1 through a Fuji dealer/official repair center. You may have to contact a dealer in Japan. I bet you can buy them factory made from the official Fuji repair center for far less then Grimes charges.

I had a set made for 75mm f4.5 Grandagon N they charged me $89 did not engrave 3rd stops like I asked and only marked it to f32. I mean WTF?:eek: Anyhow I found out I could order then from a Rodenstock dealer for around $20 for a pair w/ 3rd stops and to f45 like it should have been from Grimes.

Hey I had to wait a few weeks for Grimes to custom engrave the scales, So if you have to wait a couple of weeks to get them from Japan it wont be much longer and I bet you save the cash so you may as well try.

Just a thought.

Daniel Stone
27-Jan-2013, 17:50
Dan,
This lens is planned to remain "in the fold" :), but having a pretty aperture scale applied and measured accurately might silence the voices in my head long-term in regards to its true accuracy ;)

The "other option" would be to have T-stops done(since I shoot mostly transparency film now) instead of f-stops, if we're getting really cwazee :D

Nathan Potter
27-Jan-2013, 17:59
I also have had questions about cell spacing on obviously modified lenses as well as unmodified samples.

1. Generally new and unmodified lenses: If spacers are present between cells are they always the same number and/or thickness for every lens of the same model? Or put another way: Do the top manufacturers customize the spacers for each individual lens?

2. Is there a spec published by any of the big producers on the spacer requirements for lenses made by that particular producer indicating actual dimensions that we could measure using a micrometer, or is a custom adjustment made on a optical bench using an actual resolution test like a star or resolution target at the factory?

Scanning back threads here seems to produce less than definitive answers to these questions.

Nate Potter, Austin TX.