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View Full Version : Problem mounting Fujinon lens - please can anyone help?



Riverman
23-Oct-2011, 12:10
I have a Fujinon 300mm f8.5 lens in Copal 1 shutter that I am trying to mount in a Canham board.

When trying to mount the lens today I noticed that a small screw was sticking up and preventing the lens board from sitting flush to the shutter: see attached images.

I have other LF lenses (including another Fujinon that is also in a copal 1 shutter) and none of them have this protruding screw.

Is this a fault with the lens? Should I attempt to unscrew the protruding screw? Any advice or pointers very gratefully received.

Thanks

BrianShaw
23-Oct-2011, 12:11
Yes, you can remove it. Or you can notch the board to accomodate the screw. It is intended to keep the shutter from rotating but there is little risk of that if the shutter is properly attached.

Riverman
23-Oct-2011, 12:29
Thanks Brian. Very helpful.

Riverman
23-Oct-2011, 14:09
Would anyone happen to know what size screwdriver I need to unscrew this screw (very small I'm guessing)?

Gem Singer
23-Oct-2011, 14:16
Riverman,

The small screw in your picture is called an index pin. It comes standard on new Copal 0 and Copal 1 shutters.

Most lens manufactures use Copal shutters nowadays, so it bears no relationship to the brand of lens mounted in the shutter..

Some brands of metal lens boards come equipped with a notch or recess for the index pin. However, Canham boards do not.

Simply remove the pin with the proper sized eyeglass repairer or jeweler's screw driver.

It does not affect the operation of the shutter.

Be sure to tighten the retaining ring sufficiently so that the shutter cannot turn in the lens board, and it will be fine.

Alan Gales
23-Oct-2011, 14:20
Stanley used to make an inexpensive set of small screwdrivers that came in a 2 piece hard plastic case with a clear lid and the bottom piece in red. They were readily available at most hardware stores. I bought my set years ago. If these are not available now I'm sure something has take it's place. Just check your local hardware store.

Tony Evans
23-Oct-2011, 14:39
NexXtech Electro Screwdiver Set, at The Source (in Canada), Radio Shack (in USA).

Leigh
23-Oct-2011, 18:11
The pin is an anti-rotation device.

It engages a small slot on the periphery of the lensboard hole, and prevents the shutter from rotating and coming loose.

I use them on all the lenses I mount, although many folks prefer to remove them.

I've had shutters lacking the pin rotate and come loose.

If you want to use the pin as intended, take a file, drill bit, or hacksaw blade and cut a small clearance slot at the 12 o'clock position on the lensboard hole.
The pin is less than 1/10th inch in diameter, so the slot need be no larger than that, and only half that depth.
The hole can be any shape as long as it clears the pin. It need not be pretty since it's not visible when the shutter is mounted.

- Leigh

Riverman
24-Oct-2011, 10:59
Thanks so much for these helpful replies. What did newbies do in the pre Internet age? This board is extremely valuable.

E. von Hoegh
24-Oct-2011, 11:16
What did newbies do in the pre Internet age?

Lenses didn't have those locating screws back then.

Leigh
24-Oct-2011, 11:22
Lenses didn't have those locating screws back then.
They most certainly did. All of the shutters from the 1930's-1950's that I've repaired had the anti-rotation pins.

They've only recently been omitted from new production shutters, probably to save money.

- Leigh

E. von Hoegh
24-Oct-2011, 12:01
They most certainly did. All of the shutters from the 1930's-1950's that I've repaired had the anti-rotation pins.

They've only recently been omitted from new production shutters, probably to save money.

- Leigh

It was a toungue-in-cheek comment. Should have added the winking smiley.:o