Anybody Ever Diffuse a Condensor Enlarger?

[John H. Henderson]

I have an upcoming employee art show at work, and looking back at all of my pict ures from the last year - 35mm, 6x6 and 4x5, I was disappointed to find that wha t I thought my best picture was on 35mm. I'm enlarging it to 11x14 on my Omega D3, and the film grain enlarges all too well!

I thought that perhaps a diffuser enlarger would hide the grain some. Any comme nts? I was wondering if I could put some kind of diffusing material above the n egative carrier. Has anybody tried this? Does anybody have any suggestions to a very economical material to try? (I'm NOT taking the ground glass out of the back of the Toyo!)

Thanks for any comments and suggestions.

[mark lindsey]

I suppose you could diffuse it, but remember that the loss of light from the diffusion will cause you to need more exposure time and this means more heat on your negative which can cause your negative to "pop" out of focus. Your negative is also exposed and developed with a condenser light source in mind, so expect a change in contrast.

[Peter Hughes]

A peice of white plexi. But, as Mark point out, the light loss will be considerable. I suggest upgrading your head to a Chromega lamphouse, which will provide you with diffusion AND plenty of light PLUS you can print color with it.

You might also rethink your paper and paper developer.

[Doug Paramore]

John: This might help a little...try part of the exposure through a piece of crumpled clear cellophane, such as a cigarette package. Try it for 1/2 to 1/3 of the exposure. You will get a little overall diffusion, but it won't eliminate the grain completely. You might also try a slight diffuson filter for part of the exposure. As the other guys said, white plastic will work but it kills the light if you get enought diffusion above the neg to do any good. I tried for months to tame the light on my D-2 condenser system and finally gave up and bought a cold light head. I have never regretted buying the cold light head. Doug.

[Paul Schilliger]

I had done this on my Durst Laborator 45 for Ilfochrome prints: I replaced the o riginal 150 W bulb by a twin 250/500 W quartz and fitted a small fan in a box relied to the lamp housing by a hose. This gave me plenty of light allowing for a thin ground plexi on the light travel.

[David Grandy]

I use a Omega D-5 XL with a colour head and while diffusion certainly helps by reducing dust on the negs I've never thought or read that using such a head would reduce grain. A condensor enlarger will have more contrast and the grain may appear sharper, but it's the same grain.

Although I use 4X5 I've never been concerned with 35 mm grain, as long as the image is razor sharp. The lack of grainyness in a LF print is nice but less important to me than the detail the big neg gives along with better shooting controls.

[David H. Miller]

I converted my D-2 to coldlight more than 20 years ago and am still happy. That's why I'm converting the 5x7 Elwood I'm restoring, too.

Best of all for 35mm, buy the Book of Pyro by Gordon Hutchings, some HP5+, and some pyro from Photographers Formulary. Use it carefully, and you'll say goodby to grain and praise the stain!

Seriously, it's smooth and marvelous. With a coldlight its amazing what you can get from the highlights, too. Then get a Metrolux so you can make the same print again and again.

Dave

[Blake]

Stephen Shuart sells flashed opal diffusion glass cut to fit your condensors...he's in shutterbug. I've used zero'd magnifier sheets (fresnel looking 8x10 plastic sheets found in the school supply section of my local Wal-Mart) cut to fit in my condensors...the light loss is minimal and it serendipitously fixed my uneven illumination probs.

[Dave Schneidr]

This may be a obvious, but where do you put the flashed opal glass or the plexiglass if you are trying to slightly diffuse the light from a condenser? Does it go above the moveable condenser lens, between the moveable and fixed condensers, or just above the negative carrier? Many recommend a sheet of heat absorbing glass if you use the 150 watt bulb in the D5 condenser lamp house, where does the heat absorbing glass get installed?

[Paul Schilliger]

The heat absorbing glas should be at the exit of the bulb housing, maintained in a special cooling tray, and the diffuser in the filter drawer. (At least this is what I did).