How to adjust a condenser enlarger?

Luke_H · Jul 23, 2006

Hello everyone. I'm new here, and would like to figure out how to adjust the condenser head in an Omega enlarger I use in a college course.

The contrast I'm getting out of my prints only reaches what I consider 'normal' range when I'm using a #3 Ilford filter on Ilford's MC paper.

I've heard that you can control contrast to a degree by moving around the lenses in the head. However, the instructor won't go over it with us, or seems to not want me to mess with my enlarger. It won't be hard for me to put them back into place how I found them, so I'd like to at least know the proceedure, or what adjustments cause an effect on the contrast in the prints.

I can't remember what model my enlarger is, but I want to say it's an Omega or Besseler. It has a rectangular head with about 3 lenses on 'shelves' inside by the light bulb.

Anyway, if anyone can shed any light on the issue, I'd love to hear it.

Thanks,

Luke

ksmattfish · Jul 23, 2006

I've never heard of this, and I use an Omega condenser enlarger and a Beseler condenser enlarger. One good reason not to fool around with the condesers would be that dust or scratches can be a nightmare. Leave them alone, safe in their housing unless there is a problem.

Contrast is controlled by a lot of different things. I'd just work on controlling it with exposure and development of the film. Increase contrast by underexposing and increasing development. Decrease contrast by overexposing and under developing.

Agitiation also affects contrast. Do more shaking for more contrast, slow down for less contrast.

I don't really see any problem with you getting "normal" contrast at grade 3. 2 or 2.5 is usually considered in the middle of the scale. I print a lot of my stuff at grade 3. Your idea of normal contrast is probably different from the next guy anyway.

Philip Weir · Jul 23, 2006

Must agree with "ksmattfish" The only enlarger I can remember using where you fiddle with the condensers is a Durst 138, where you would change the condensers to concentrate the light for a smaller negative. It sounds like a funny enlarger to have the lenses inside by the light bulb. The light bulb should be above the condensers and the lens below that. Maybe you have an upside down enlarger. [only kidding] Philip.

ksmattfish · Jul 24, 2006

Philip Weir said:
The only enlarger I can remember using where you fiddle with the condensers is a Durst 138, where you would change the condensers to concentrate the light for a smaller negative.

Yeah, I think that's fairly typical. My Omega DII has a set of big condenser lenses for 4x5 and 120, and some little ones for 35mm. Although I have never had any problems just using the big condensers when printing 35mm. It probably adds a little exposure time, but not worth that hassle of switching them out all the time for the 35mm printing I do.

My Beseler enlarger changes the position of the enlarging lens for different formats, but that's probably because it's designed for the condensor head to be switched out for a diffusion head.

nealjpage · Jul 24, 2006

We had two in our college darkroom that had movable glass lenses (i guess that's the term) inside the head. One was a Besseler 67 and the other was an Omega D2. i was never able to figure out the best position for them either. I think Phillip is correct: it has something to do with the size of your neg. I dunno....

Luke_H · Jul 24, 2006

I might have just been misinformed then. I'll continue to use filters. I typically end up using #3-#5 to give the photos some oomph. I am not a fan of the color gray I guess.

Thanks for the responses.

ksmattfish · Jul 24, 2006

Luke_H said:
I might have just been misinformed then. I'll continue to use filters. I typically end up using #3-#5 to give the photos some oomph. I am not a fan of the color gray I guess.

If you are using #5 to get "normal" contrast, you definately need to increase the contrast of your negs. #5 usually won't be solid black and white with no gray, but it should definately be very high contrast.

If you want solid black and solid white you need to get some lith film. Enlarge your photo onto the lith film (comes in sheets), and then you can make contact prints with no gray.

Torus34 · Jul 24, 2006

Old engineering maxim: 'Never open something up to see why its working right.'

Luke_H · Jul 24, 2006

I typically shoot with the spot meter and bracket one stop either way, resulting in 3 images to work with. I have been shooting/developing everything at it's intended speed. My prints have the correct range. I probably just have a different opinion of what looks correct, having spent most of the past year and a half scanning my b&w negatives.

#5 renders the images mostly black or white. It also brings out grain to a high degree. #2.5 is more around what the instructor considers correct looking.

There are other students who have switched to different enlargers (of the same make/model) in the room and had huge increases in contrast, so I was just curious. I imagine the number of hours on the bulbs, or the bulbs themselves have an effect. I've just been putting up with my enlarger like a beat up pop gun at the fairgrounds.

ksmattfish · Jul 24, 2006

Regarding your initial question, possibly what you heard was that condenser heads have higher contrast than diffusion heads.

mysteryscribe · Jul 24, 2006

my thought is that if the equipment belongs to the school and they dont want you messin' in the head, you probably would be better off to leave it alone.

They tend to frown on people tinkering with their stuff. Well they used to at least.