How many inches across is copal 0 opening?

[gardnermounce11]

There's a seller on ebay selling a lens board at a steal. I don't think he knows what he's selling as I've asked him what copal it is and he hasn't responded, though he did post a photo of himself measuring the opening which looks to be right at 1.5 inches. Does anyone know copal sizes in inches? If it's #0 then I'm jumping on it, but I want to be sure.

[c.d.ewen]

Look it up here (http://www.skgrimes.com/products/index.htm).

Charley

[Gem Singer]

Copal 0 opening= aprox. 35mm= approx. 1.4 inches.

1.5" sounds right for a Copal 0 shutter, measured roughly.

[gardnermounce11]

Copal 0 opening= aprox. 35mm= approx. 1.4 inches.

1.5" sounds right for a Copal 0 shutter, measured roughly.

"Measured roughly" is putting it lightly ;)

[Gem Singer]

Lens board openings are usually metric, and it's difficult to measure millimeters accurately with a ruler. Even more difficult to measure the diameter of a circular opening.

I/10th of a millimeter is insignificant when it comes to lens board openings. There is plenty of room error.

I'm quite certain that it is a Copal 0 opening. However, if you have doubts, don't purchase the lens board.

[Jeffrey Sipress]

http://photoweb.net/pw_tech/copal.html

[Bob Salomon]

How do you know it is a "steal"? What camera does it fit?

[Leigh]

The correct mounting hole diameter for a Copal #0 shutter is 34.8mm, which is 1.370 inches (mighty close to 1 3/8" which is 1.375").

The hole is larger than the shutter threads because there's a lip on the shutter side of the retaining ring.

This is apparently done to avoid damaging the shutter threads when mounting, by providing extra clearance. (Just speculation on my part.)

- Leigh