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John Randall
17-Jul-2000, 19:51
I have an Omega ProLab Variable condensor enlarger and have read that a diffusio n enlarger is better than a condensor enlarger. My question is, if I replace the incandescent lamphouse with a coldlight head and then remove the condensors wil l this result in a diffusion enlarger?.

Doug Paramore
17-Jul-2000, 20:12
John: The coldlight cell goes in the place where the condensers are, inside the big aluminum tube and right on top of the negative. Unplug the cord to the light bulb and plug in the two cords to the cold light head. Takes about ten minutes to convert. It is worth it. The highlights glow with cold light, and you will do a lot less spotting. The effect is the same as a diffusion enlarger. You won't want to go back to the condensers.

John Randall
17-Jul-2000, 20:27
Thanks a lot. I'm going to do it as soon as I find a coldlight head.

M.
18-Jul-2000, 01:50
Many people prefer their perception of greater apparent sharpness of prints made with a condenser enlarger. No flames please.

Pete Andrews
18-Jul-2000, 11:19
I can never understand why people are so eager to give up a perfectly good condenser source for the dubious "advantages" of a cold light head. One cold-light system actually pre-heats the negative stage, a bit pointless surely? And since most condenser enlargers are actually semi-diffused anyway (most of them use a diffuse opal bulb), the difference, purely in terms of the Callier effect, is quite unremarkable.

Blake
18-Jul-2000, 11:50
I have to agree with Pete especially when you consider that a condensor source can be double diffused with opal glass for about ten dollars and the difference is even more unremarkable including the dust probs. Soak your money into a good enlarging lens instead.

John H. Henderson
18-Jul-2000, 12:39
Where does one find this "opal glass?" A big city photo shop? Home Despot?

Charlie Stracl
18-Jul-2000, 13:49
The serious recent analyses of diffusion vs. condensor seem to indicate:

You can get virtually equal results if you adjust development to match your light source. There are slight differences, but they are really very slight if you adjust your development/

The advantages of diffusion seem to be a very slight improvement in not seeing dust and very minor scratches.

So, as far as I'm concerned:

1)If you have an enlarger with a light source that works well, stick with it.

2)If you are buying a new enlarger without a light source, a cold light head is the least expensive light source available for B&W. Be sure to get one that has green and blue phosphors so you can use VC paper. These tubes work fine with graded papers, too. A 4x5 cold light for your Omega runs about $200 new. None of the enlarger manufacturers come close to that price for any 4x5 light head.

3)For color work and B&W, most enlargers are diffusion, but not cold light. They work fine, too.

In my early years I had a cheap condensor enlarger and was very happy with it and the images it produced. Then I had a Zone VI VC cold light enlarger. I didn't like it, but only because the light wasn't bright enough for me to focus easily and it really didn't work well for smaller formats. Now I've got Saunders enlargers (color diffussion) and I really like them.

The Omega 4x5 enlargers are workhorses. I would stick with the condensors if they are working for you. If you need to print negatives of a size for which you do not have the condensor, a 4x5 cold light might be cheaper than the smaller condensors. Otherwise, spend your money on lenses, paper, a fine easel, and other tools.

By the way, substituting a different light source will not in any way damage your enlarger or condensors. Just be sure to treat the condensors with great care. They are crude optics, but scratches on their surface can be focused by main lens, which can ruin your print.

Blake
18-Jul-2000, 13:56
John try,

www.stephenshuart.com

Blake
18-Jul-2000, 13:59
sorry for being so ineffecient with my multiple postings,

click on Jena Optical glass then scroll to opal diffusion glass, 28 bucks.

Paul Schilliger
18-Jul-2000, 16:15
Having so many enlargers specialists at hand, I seize the opportunity to jump in and ask a question -excuse me, John- that is not directly relevant to your question: Can a scratche d condenser be repared? One of my old Durst Laborator main condenser has a nice scar in the middle of th e convex surface, and it appears on the paper when the lens is focussed. Any hint? I think I had seen, b ut longtime ago, a product that could fill and obliterate scratches in glas. Never saw it again since. Than ks!

Pete Andrews
19-Jul-2000, 07:56
Paul. Try an auto-windscreen repair specialists. They have some amazing "glues" that can fill quite deep chips and scratches. They might even do the job for you, if you can get chatting to one of their repairers. Make sure that the scratch is thoroughly cleaned out before hand. The transparent filler can be scraped flush with the glass with a scalpel blade, and polished down with metal polish. I shouldn't think the surface finish of a condenser is too critical. Don't know how the repair'll stand up to heat though.

Paul Schilliger
19-Jul-2000, 14:08
Thanks, Pete. Excellent idea! I will explore this possibility.

Doug Paramore
19-Jul-2000, 16:36
The color heads with built-in filtration for LF format enlargers will give much the same effect as the cold light heads. Those that use the high intensity light bulbs through a diffuser box work well. The only negative part is that they use up expensive light bulbs quickly. I won't quarrel with those who like the condenser enlargers. I converted mine several years ago and have never been sorry. The I had was blocking up of highlights, which can be compensated for with development. I don't like to have to compensate for over exposed negatives with development for every shot with lots of contrast. In my considerable efforts to control the contrast from the condensers, I found the best solution by using white plastic sheets cut to fit the condenser carrier and placed next to the negative. When I got enough diffusion to be effective, there was little light left. Sorry, folks, but cold light does make a difference, as does the color heads.

Cameron Mosley
19-Jul-2000, 22:45
If you currently have a condenser head and want to see what a print from diffused light source looks like, simply look at your contact sheets. This is a fairly accurate representation of a diffused print. If I print my contact sheets with a #3 filter ( using a condenser head), I will usually have to print the enlarged negative with a 2 - 2 1/2, and it still doesn't compare to the tonal range of the contact print. From my experience, you lose a zone's worth of detail in the highlights with a condenser head. That being said, you can still achieve excellent results with a condenser light source, but I would try both before making ruling one out.