Diffusion vs Condensergreenspun.com : LUSENET : Large format photography : One Thread
Having read of the differences in final prints between using a diffused light sourse or condenser, I am curious to see the differences on my own prints. Not having oodles of $, space, etc., I must use only my D2 (condenser). I was wondering if I placed a thin, opaque plastic sheet under the condenser & over the neg. carrier if that might create the conditions to guage a real difference between the two? (Adjusting for a new D-max).
I notice that my contact prints (4x5) have much better tonal scale & detail in the denser parts of the negative - is this a result of a print made without the effects of the condenser? Thanks for any feedback I really enjoy this forum and am learning lots! Cheers, Matthew.
-- Matthew Hoag (firstname.lastname@example.org), March 23, 2001
Hi, Matthew, If you look back on older posts you'll probably find some discussion about it. And certainly you'll find some contradiction. For sure, it can be stated some few points: 1- some diffusion is always welcome for the purpose you want (printing a step wedge can show it pretty fast); 2- there'll be some, maybe expressive, light loss; 3- one should be careful not to print some diffusion texture; 4- a softer head may leave you more confortable to explore controls on exposure and development of modern emulsions. In short, try it. It can be the shortest and cheapest way to work with two heads in one. Good work. Cesar B.
-- Cesar Barreto (email@example.com), March 23, 2001.
Matthew: Several years ago, I tried to place a diffusion disc over the neg to approximate the cold light effect. I used sheets of white semi-transparent plastic. I found that when I used enough diffusion to kill the effect of the condensers, the light was too dim for effective printing. I gave up and bought a used cold light head for my D-II. I have never been sorry I did. The effect you get with a cold light is about the same as your contact print. You don't lose the detail in the highlights and there is a much better tonal scale. You may gain some highlight detail and tonal scale by backing off your development time for film. Check with Midwest Photo Exchange for used cold lights. They get them from time to time and the price is usually pretty good. The tubes in a cold light head are supposed to last for about 10,000 hours, so the cost is pretty cheap. You should be able to get one for about $150 used, and it is a drop-in installation. A straight diffusion head will also give you the same effect as a cold light. The modern color heads are diffusion, but are much more expensive than cold light. A cold light head is an excellent investment if you are serious about printing.
-- Doug Paramore (firstname.lastname@example.org), March 23, 2001.
Mathew, 4 Months ago I converted my Omega from a condenser to a diffusion enlarger, and posted detailed instruction on how to do it on this site. Unfortunately, I may have filed it under the wrong category, nvertheless look in the "Darkroom:printing" category,and you will find it there.
-- Andre Noble (email@example.com), March 23, 2001.
Contacts(and Polaroids which are contact prints) have a much extended tone scale because the picture hasn't gone through a lens, even the best lens has some dispersion, cannot do anything about it, this produces loss of range, Condensors have "shaper" and more contrasty pictures, mor problems with scratches and dust. Diffused(cold light or light box0 is "softer" and makes retouching less needed. Try and try until you find what pleases you. Enjoy
-- Andrea Milano (firstname.lastname@example.org), March 26, 2001.
I too placed a diffuser just after the heat absorbing glass and had a drastic light falloff. I replaced the tungsten bulb by a 500 W halogen and installed a fan system. This was working well for Ilfochrome prints. But the Ilford color control filters were in steps sometimes too far apart and a color head would have given me more control. Many labs get rid of beautiful enlargers for next to nothing due to the trend for digital prints.
-- Paul Schilliger (email@example.com), March 26, 2001.