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soupdragon

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Help needed again.

I have a Nikon W 360 6.5 lens.
It all works but the aperture ring is rather too stiff in operation.
I don't want to return the lens as the dealer will only offer refund but not service or repair and it is my favourite optic.

So, is there anyone in the UK that can service copal 3 shutters?

On a slightly more technical level, can I fit the front and rear element groups of the Nikon into my Schneider Compur 3 shutter which is f5.6?
 
I thought we'd maybe been here...

Is there a spacer, normally a metal ring, between the shutter and the lens board?

Is the aperture ring still too stiff when the lens is removed from the lens board all together?
 
The role of the spacer is to prevent overtightening, resulting in a pinched aperture ring...
 
Linhof & Studio does servicing of shutters: https://www.linhofstudio.com/large-and-medium-format-camera-servicing/

Does your "Schneider Compur 3 " already have a lens mounted in it? If so, and it were mine, I'd prefer not to swap lenses out. In any case, while the No. 3 Copal and the No. 3 Compur are interchangeable, the aperture scale on your No. 3 Compur would not be correct for your 360 mm Nikkor W.

Also I'd say to be sure to consider MartyNL's posts.

Just curious, what's the top speed on your No. 3 Compur?

David
 
David Lindquist said:
Linhof & Studio does servicing of shutters: https://www.linhofstudio.com/large-and-medium-format-camera-servicing/

Does your "Schneider Compur 3 " already have a lens mounted in it? If so, and it were mine, I'd prefer not to swap lenses out. In any case, while the No. 3 Copal and the No. 3 Compur are interchangeable, the aperture scale on your No. 3 Compur would not be correct for your 360 mm Nikkor W.

Also I'd say to be sure to consider MartyNL's posts.

Just curious, what's the top speed on your No. 3 Compur?

David
Click to expand...
The Compur has a top speed of 1/250 with an aperture of 5.6.
Whilst this is larger than the Copal I could work around it.
 
MartyNL said:
I thought we'd maybe been here...

Is there a spacer, normally a metal ring, between the shutter and the lens board?

Is the aperture ring still too stiff when the lens is removed from the lens board all together?
Click to expand...
The back of the Copal shutter has a step in the machining which holds the aperture ring clear of the lens board.
I did take it off the board and it's remains as stiff to operate.

The aperture ring also goes way past the f64 marking which leads me to think something has failed internally or I have knocked it somehow.
 
Ok.
Have you tried the aperture without the lens cells fitted?
I've had instances when the lens cells have been so tightly screwed in that they impinged on the operating mechanism.

The aperture going way past f64 is quite normal. I believe this is what a tiny screw was for on the back, to act as a limiter, but the lens is totally fine without the screw and most people remove it.
 
MartyNL said:
Ok.
Have you tried the aperture without the lens cells fitted?
I've had instances when the lens cells have been so tightly screwed in that they impinged on the operating mechanism.

The aperture going way past f64 is quite normal. I believe this is what a tiny screw was for on the back, to act as a limiter, but the lens is totally fine without the screw and most people remove it.
Click to expand...
OK, figured out the problem.
I took the shutter out of the lens cells and the mechanism was still stiff.
I wanted to remove the aperture setting ring but this appears more complex than I had anticipated.

Eventually I decided to clean where I could using cotton wool buds and Kami scanning fluid.
After a matter of moments the aperture ring was moving more freely.
The cotton wool buds removed a considerable amount of dirt and what could be grease.

Having repeated the process for about 20 minutes, the ring now moves as expected.

I'm not convinced I have sorted the problem long term as I suspect I have just diluted whatever substance was causing the stickiness.

I hope that with regular cleaning the magnitude of the problem will diminish.

My only fear now is that whatever it is will migrate somewhere inaccessible.
 
Last edited:
Good news about your aperture ring.
The excess rotation is because the shutter is a general-purpose item, intended to be used with a variety of lens cells, each with different focal lengths. The physical size of the aperture will be different for each focal length and the apparent excess is there to accommodate this.
You will notice that the shutter speeds are permanently engraved (1/60th is always 1/60th whatever the focal length*) but the apertures are on a separate metal strip wrapped around the barrel
You can safely use the extra-small apertures beyond f64, as the aperture mechanism is independent of the shutter, but you may then encounter problems of diffraction. These are discussed very extensively elsewhere on the web, if you care to look. Diffraction fuels a good deal of debate.

* This is not perfectly true, but an explanation belongs in a different thread.
 
Great news about freeing up the aperture ring!

And while you may be right regarding the lube scenario's, I believe a great number of these lenses, especially the big one's, just haven't had the use and care/storage of their smaller relatives. Bearing in mind, they've been designed to consistently deliver in professional, and not amateur conditions.

Recently, I picked up some gear from someone deceased. All of the kit was spotless but had lacked use and left sitting in an unlived in home. Most of the prontor shutters felt a little lazy at the slower speeds at the time, especially the 240mm. But once I got them home, gave them some time to acclimatise followed by a little gentle exercise, they stated behaving as normal.

They need regular use and not sat idle, something I'm been a little guilty of, of late.
 
David M said:
Good news about your aperture ring.
The excess rotation is because the shutter is a general-purpose item, intended to be used with a variety of lens cells, each with different focal lengths. The physical size of the aperture will be different for each focal length and the apparent excess is there to accommodate this.
You will notice that the shutter speeds are permanently engraved (1/60th is always 1/60th whatever the focal length*) but the apertures are on a separate metal strip wrapped around the barrel
You can safely use the extra-small apertures beyond f64, as the aperture mechanism is independent of the shutter, but you may then encounter problems of diffraction. These are discussed very extensively elsewhere on the web, if you care to look. Diffraction fuels a good deal of debate.

* This is not perfectly true, but an explanation belongs in a different thread.
Click to expand...
Thanks.
I'm learning all the time here.
 
MartyNL said:
Great news about freeing up the aperture ring!

And while you may be right regarding the lube scenario's, I believe a great number of these lenses, especially the big one's, just haven't had the use and care/storage of their smaller relatives. Bearing in mind, they've been designed to consistently deliver in professional, and not amateur conditions.

Recently, I picked up some gear from someone deceased. All of the kit was spotless but had lacked use and left sitting in an unlived in home. Most of the prontor shutters felt a little lazy at the slower speeds at the time, especially the 240mm. But once I got them home, gave them some time to acclimatise followed by a little gentle exercise, they stated behaving as normal.

They need regular use and not sat idle, something I'm been a little guilty of, of late.
Click to expand...
I know where you're coming from.
Not so long back in my Hasselblad days, the entire camera/lensfilm back would be temperamental without use.
 
Well, the aperture setting ring became stiff again shortly after my first attempt at cleaning.
After a few very large glasses of Brandy I decided to remove the two screws that are visible on the setting ring.
To my surprise the steel adjustment ring could be easily lifted out of place.

Sadly I did not photograph this but what I found was a punch formed nylon shim designed to create the correct friction for the aperture ring. Both this, the adjustment ring and the anodised aluminium face of the shutter body were effectively glued together with a low quality lubricant (I suspect amateur tinkering).
I cleaned all of the clutched surfaces with a solvent and removed any visible residues.
Yay!, complete 100% success, the aperture ring now rotates perfectly throughout the range with no change in resistance.

Getting the two retaining screws back into place was the biggest challenge as I have fat fingers and poor eye sight.

Result............
 
Glad to hear you got the stiff aperture ring sorted out. I hate working with those really tiny screws. If I'm smart, I avoid it.

Thank you for the information on your Compur 3. I have a brochure from Prontor dated 1988 (by then production of the Compurs had been moved to the Prontor works) showing that the then newest version of the No. 3 Compur had the top speed increased to 1/250 sec.

During the period of time that both the No. 3 Copal and the No. 3 Compur were in production, I wonder how the production numbers of the two compared.

David
 
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