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RussHerm
30-Nov-2012, 14:24
Hi gang

I'm still a noob to LF (having only shot a few dozen sheets or so), and I'm not so accomplished at QUALITY DIY (thank goodness for duct-tape!)

I just ordered a pair of old lenses... Both Copal 3 shutter size, but only one lens has a good shutter...

Seeing as how Copal 3 shutters are much more $$ than I thought, i will need to wait on buying another shutter.

I plan on shooting each lens with the same shutter for the time being (I realize the f-stop will not be accurate for the other lens, but that is an easy calculation)

My question: are there any specific tools I should order while I wait for shipping so I can hit the ground running when the lenses arrive?

Also, are there any resources where I can study up on how to swap the shutter?

Thanks!
Russ

BrianShaw
30-Nov-2012, 14:31
Put away the duct tape, vice-grips, and WD-40 please.

The cells should screw out of one shutter and screw into the other. No tools should be required. You can move the aperture plate easily with a very small screwdriver.

Are you sure that the shutter is broken enough to need replacement, or might a good servicing bring it back to life?

RussHerm
30-Nov-2012, 15:24
That's great news Brian, thanks!

The other lens actually is a barrel lens that I intend to cover the front of it with the shutter... Sounds aweful, I know... But I read it in an article for this lens/shutter combo - and I couldn't b more excited

JBAphoto
1-Dec-2012, 16:14
Aaaargh! - Just use the shuttered on at the moment, or use the barrel one for dark situations. Don't mess around as damage repair is more expensive than waiting here or on APUG for the length and shutter you want at a sensible price

The ideal shutter for barrel mounted lenses is a Sinar Shutter, but that is another whole level away

Bogdan Karasek
23-Dec-2012, 13:16
Hi gang

snip
.......... (I realize the f-stop will not be accurate for the other lens, but that is an easy calculation)
snip

Thanks!
Russ

hello,

How easy is that "easy" calculation?
I have a Compur #1 and I have the following cells:
Symmar 150/5.6
Beck 150/3.8
Componon 210/5.6
Geronar210/6.8

The Compur #1 has an aperture plate with f4.7 > f32.

What is it that I have to do now if I want the right f stop for my exposure?

Regards,
bogdan

Bob Salomon
23-Dec-2012, 13:21
hello,

How easy is that "easy" calculation?
I have a Compur #1 and I have the following cells:
Symmar 150/5.6
Beck 150/3.8
Componon 210/5.6
Geronar210/6.8

The Compur #1 has an aperture plate with f4.7 > f32.

What is it that I have to do now if I want the right f stop for my exposure?

Regards,
bogdan

Lenses like the 150/5.6 fit a 0 shutter, not a 1 size shutter.

IanG
23-Dec-2012, 13:50
Lenses like the 150/5.6 fit a 0 shutter, not a 1 size shutter.

According to Schneider themselves the 150mm f5.6 Symmar was in a #1, this must be the older version though, Schneider don't give a date for their historical data. Later 150mmSymmars are in size #0 as you say.

Maybe this was because of the short lived splitable set with it's range of cells, sort of casket set, that all fit the same shutter.

There's some 150mm f5.6 Symmars on ebay at the moment on Compur #1 shutters.

Ian

IanG
23-Dec-2012, 14:14
hello,

How easy is that "easy" calculation?
I have a Compur #1 and I have the following cells:
Symmar 150/5.6
Beck 150/3.8
Componon 210/5.6
Geronar210/6.8

The Compur #1 has an aperture plate with f4.7 > f32.

What is it that I have to do now if I want the right f stop for my exposure?

Regards,
bogdan

If you know what lens was originally in the shutter (focal length) you can easily use a spreadsheet to calculate the actual apertures for each set of cells in comparison to the current markings.

F number = focal length divied by the diameter (of the aperture). So you back calculate the dameter for each current marked stop and then calculate the actual apereture for each set of cells based on their focal length.

Ian

Dan Fromm
23-Dec-2012, 14:56
Bogdan, there's an easy way.

Put the cells in the shutter. Hold the shutter at nearly arm's length with the front cell facing you. Slowly open the aperture until the diaphragm leaves just disappear. Slowly close the aperture until the diaphragm leaves just appear. Repeat a couple of times to be sure. Look at the aperture scale. The indicator will point to "wide open" for the cells fitted. Make a note of where it is. If it is to the left of the smallest number (indicates, in your case, an aperture larger than f/4.7) you're in trouble, this procedure won't work. If it is to the right (indicates an aperture no larger than f/4.7), to stop the lens down n stops, move the aperture across n f/stop markings, positioning roughly as far between marks n and n + 1 as it was between the markings it was between when the lens was wide open (half-way, for example). Calculations aren't needed if you can count on your fingers.