help for a novice

[don lee]

First time on your site but pretty familiar with old gear. Question is what am I missing to mount this lens to the lens board? thanks!



153252

[B.S.Kumar]

Welcome!

You need to mount the universal iris to the lens board first. Drill the appropriate holes in the board to do that. Then it is simply a matter of opening the iris, inserting the lens into the opening and closing the iris to hold the lens firmly. If the lens is heavy you may need to figure out a way to support the weight.

Kumar

[don lee]

Welcome!

You need to mount the universal iris to the lens board first. Drill the appropriate holes in the board to do that. Then it is simply a matter of opening the iris, inserting the lens into the opening and closing the iris to hold the lens firmly. If the lens is heavy you may need to figure out a way to support the weight.

Kumar

Ah so does the Universal iris grab the lens on the end with threads?
that makes sense because i can see nail holes where it came loose from the board.
I assumed the lens protruded through the board and was held by a retaining ring but was confused because the hole isn't big enough.
thanks very much

[Steven Tribe]

Yes the cut hole in the lens board is too small to utilise the range of diameters offered by the universal iris clamp.

Note that the clamp has two controls. One wing nut allows movement and secure clamping, the other makes adjustment so that the iris blades "go into" the lens thread. So:

1. release clamp nut.
2. position the lens and move the iris in whilst still holding the lens.
3. maintain slight pressure on the movement nut and at the same time turn in the locking nut.
4. check that lens is really clamped (Wiggle!).

I wouldn't personally reccommend the system for lenses weighing over about 0.5 kilo.

[don lee]

Yes the cut hole in the lens board is too small to utilise the range of diameters offered by the universal iris clamp.

Note that the clamp has two controls. One wing nut allows movement and secure clamping, the other makes adjustment so that the iris blades "go into" the lens thread. So:

1. release clamp nut.
2. position the lens and move the iris in whilst still holding the lens.
3. maintain slight pressure on the movement nut and at the same time turn in the locking nut.
4. check that lens is really clamped (Wiggle!).

I wouldn't personally reccommend the system for lenses weighing over about 0.5 kilo.

[don lee]

That's great I appreciate your help. Silly me, I saw an iris and thought it went behind the lens to control exposure!
Regards

[Drew Bedo]

don lee: I may be wrong, but hat lens clamp is not a common item. Take care of it.

[Steven Tribe]

Universal iris clamps were a cheap item around 1900. Not any more! They are really useful items, especialy when many lenses have lost their flanges/rings.

It is quite easy to mistake these lens clamps for the loose irises that were also available in different sizes. I enclose a Swedish catalogue page from 1914 showing both of them with sizes available.
Most of these were no-name makers, but at least 2 firms made their own, rather more elegant, models (Clement et Gilmer and ICA). They are mostly associated with continental tailboard cameras.

[Jac@stafford.net]

They are expensive when found. I recall a post here long ago about a modern version available. Can't find it at the moment!

[Steven Tribe]

I have to admit that I have never purchased an iris clamp, although I have a number. They always came along with a reisekamera sets (13x18, 18x24 and 24x30cm) with interesting lens and lots of plate holders. The same "bonus item" phenomenum has happened with Sinar lot buys which included half hidden Sinar Copal shutters and cable releases.

[pound]

They are expensive when found. I recall a post here long ago about a modern version available. Can't find it at the moment!
Probably this http://www.chamonixviewcamera.com/irislensboard.html

[Leszek Vogt]

Probably this http://www.chamonixviewcamera.com/irislensboard.html

Does anyone know if this iris closes completely ? Thanx.

Les