johnphoto
Member
As I put more film through my new S2, I'm finding a few minor issues that may or may not need to be addressed. At 1/1000, the slit doesn't open (no light reaches the film). At first I thought that's OK, I can live without it. But now I realize that at 1/500 the right edge of the image (left side of the gate) goes a little dark. I imagine this is because the rear curtain is closing a little too quickly.
My research so far shows that there are two easy-to-get-at adjustments on the bottom of the camera under a cover plate (2 screws).
Unfortunately the two references I have disagree as to which is which. Nico van Dijk's page
http://www.nicovandijk.net/rfrepair.htm
says the rearmost shaft adjusts the tension of the rear curtain.
Rick Oleson's Tech Notes identify the rear shaft as the opening (first) curtain adjustment.
My instinct tells me to go with Rick's much more detailed description on this one. I suspect I need to slow down the rear curtain a little to fix 1/500. True? (Clockwise turn of lens-side shaft?). Does anyone have experience with this adjustment? How much of an adjustment might be needed? How much tension is it under--will it be hard to hold while the lock screw is out and the jam nut loosened?
My research so far shows that there are two easy-to-get-at adjustments on the bottom of the camera under a cover plate (2 screws).
Unfortunately the two references I have disagree as to which is which. Nico van Dijk's page
http://www.nicovandijk.net/rfrepair.htm
says the rearmost shaft adjusts the tension of the rear curtain.
Rick Oleson's Tech Notes identify the rear shaft as the opening (first) curtain adjustment.
My instinct tells me to go with Rick's much more detailed description on this one. I suspect I need to slow down the rear curtain a little to fix 1/500. True? (Clockwise turn of lens-side shaft?). Does anyone have experience with this adjustment? How much of an adjustment might be needed? How much tension is it under--will it be hard to hold while the lock screw is out and the jam nut loosened?
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Vickko
Veteran
Typically the screw closest the curtain / film plane is the first curtain (the one that opens the slot), and the screw far away from the curtain / film plane is the second curtain (the one that closes the slot).
If the shutter is closing prematurely at 1/500 and 1/1000 sec, you have to either speed up the first curtain, or slow down the second curtain. But both curtains must have sufficient speed and tension, meaning that sometimes you have to adjust both curtains. This means to speed up the second curtain, and to speed up the first curtain more.
Ideally, one would open up the camera and clean and properly lubricate the shutter components, and then do the shutter tension and speed adjustment.
And, you need to test the camera "the day after" you do the adjustment, as the camera will "settle" overnight.
If the shutter is closing prematurely at 1/500 and 1/1000 sec, you have to either speed up the first curtain, or slow down the second curtain. But both curtains must have sufficient speed and tension, meaning that sometimes you have to adjust both curtains. This means to speed up the second curtain, and to speed up the first curtain more.
Ideally, one would open up the camera and clean and properly lubricate the shutter components, and then do the shutter tension and speed adjustment.
And, you need to test the camera "the day after" you do the adjustment, as the camera will "settle" overnight.
Frontman
Well-known
Rick Olson's diagram is correct, it looks like Nico van Djik's photo has the direction wrong for speeding up the curtains. The adjustment is easy enough to do, so long as you don't let your screwdriver slip, and lose all the tension in the drum. You should use a shutter speed tester of some type to make sure your adjustment is accurate.
I would recommend adding a little tension to the first curtain, and leaving the second one alone. It's more likely that the first curtain lost tension than that the second curtain gained any. As for how much to tighten it, that's hard to say, but likely at least half a turn, probably more.
I would recommend adding a little tension to the first curtain, and leaving the second one alone. It's more likely that the first curtain lost tension than that the second curtain gained any. As for how much to tighten it, that's hard to say, but likely at least half a turn, probably more.
johnphoto
Member
I've hesitated to touch it because of the inherent inadvisability of fixing something that's 98% ain't broken. However a friend who is very adept at fixing things came by today and we whipped off the cover plate. It looks as though the adjustment is essentially the same but with a much more sophisticated and user fail-safe mechanism than that of the S shown in my earlier post. No more danger of a screwdriver slip being accompanied by a sproing noise as the shaft spins and sheds all tension. Unless I'm missing something, an anti-clockwise rotation of the worm screw will cause an anti-clockwise motion of the shaft, leading to increased speed. Following Frontman's suggestion I'll try giving the 1st curtain shaft a 3/4 turn. The image in the next post shows how minor the problem is that I want to solve: a slight darkening at the left side of the gate at 1/500. For now I won't try for fixing 1/1000.
In an excess of caution we replaced the cover plate without adjusting anything, but tomorrow I'll give it a shot.
In an excess of caution we replaced the cover plate without adjusting anything, but tomorrow I'll give it a shot.
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johnphoto
Member
ChrisLivsey
Veteran
This much appreciated.
My "new to me" S3 suffers in a similar way. Speeds up to 500th look fine, 500th shows a tolerable edge effect (only really seen on uniform Zone V test shots) but 1,000 shows definite edges effect a little worse than your 500th.
I had hoped exercise would do the trick but 10ish films on and some exercise on blank has made no difference. No way was I tackling this if the first pictures were correct but the grub screw looks do-able.
Please carry on :angel:
My "new to me" S3 suffers in a similar way. Speeds up to 500th look fine, 500th shows a tolerable edge effect (only really seen on uniform Zone V test shots) but 1,000 shows definite edges effect a little worse than your 500th.
I had hoped exercise would do the trick but 10ish films on and some exercise on blank has made no difference. No way was I tackling this if the first pictures were correct but the grub screw looks do-able.
Please carry on :angel:
Luddite Frank
Well-known
That worm-drive tension adjustment on the Nikon is the sort of engineering and build quality that cause me to love and cherish this old machinery !
So much more rewarding than blobs of injection-moulded plastic...
So much more rewarding than blobs of injection-moulded plastic...
johnphoto
Member
A 3/4 turn increase in 1st curtain tension seems to have done the trick. Edge darkening at 1/500 is now very slight, and only would be noticeable in a shot like this designed to make it visible. Added bonus: 1/1000 has opened up. A slight but acceptable darkening at the leading edge and over the second half of travel. It's now good enough for me to use until the day comes when I absolutely must send it away for a proper CLA.
I don't suppose I am the only person tinkering with cameras this Christmas day, when one is supposed to be watching football.
I don't suppose I am the only person tinkering with cameras this Christmas day, when one is supposed to be watching football.
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Range-rover
Veteran
Did you reseal the screw for now so it will hold.
Range
Range
johnphoto
Member
Since only good things happened with a 3/4 turn, I decided to give it another 1/2 turn. Good things happened. 1/500 is basically fixed; 1/1000 in uniform except for a little corner vignetting (the lens was at f/2). So I'm a happy camper.
I'm not planning on resealing the grub screw. I tightened it down, it came to me unsealed; and I'm not going to be shooting thousands of rolls, or be in a stressful environment. Its purpose is to lock the adjustment screw; who guards the guardians? The two top speeds are running a little slow so a future adjustment can't be ruled out. But they are even and I know what they are via shutter tester, so good enough.
I'm not planning on resealing the grub screw. I tightened it down, it came to me unsealed; and I'm not going to be shooting thousands of rolls, or be in a stressful environment. Its purpose is to lock the adjustment screw; who guards the guardians? The two top speeds are running a little slow so a future adjustment can't be ruled out. But they are even and I know what they are via shutter tester, so good enough.
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B-9
Devin Bro
Glad your camera is up and running again!
This is a great source of info for any of those diy'ers around here.
Thanks for posting.
This is a great source of info for any of those diy'ers around here.
Thanks for posting.