LF/ULF contact prints using 35mm enlarger as a controllable light source.

[Lachlan 717]

Finally getting around to learning contact printing now that the house renos are done…

First, I don’t have access to a room to set up as a darkroom, either permanent or temporary, so will be looking at a hydroponics grow tent. So, room will be a consideration.

It also means I will need a table top light source for exposure.

Given the cheap cost of old 35mm enlargers, especially if they have a crap lens, led me to consider it as a controllable (via stopping down/up) light source.

It will also be easy to set up/pack up.

I will need up to 7x17 and 11x14 which should be fine with 35mm base boards.

Thoughts?

[Mark Sampson]

If you use enlarging paper, a 35mm enlarger should be just fine.
If you want to use contact papers, like Azo, Lodima, or Lupex, then your exposure times will run into minutes. That's what I found when using a 4x5 enlarger to expose Azo. The common practice for this type of paper is a suspended light bulb of high wattage.
Of course alt-processes, platinum, salted paper, etc., require a great deal of light, like sunlight.

[Oren Grad]

Yes, that makes perfect sense. I use my 4x5 enlarger with color head as my light source for contact printing with standard variable contrast papers, because that's what I already own. But there's no reason a 35mm enlarger couldn't serve as well.

[Lachlan 717]

Thanks, Mark and Oren.

This is going to be the charcuterie board for contact prints. If I like it, I’ll probably order the main course.

[xkaes]

As mentioned, it should work fine, as long as the column gets high enough with your (unspecified) lens -- set at "infinity". One thing to keep in mind that all enlarging lenses (in your case, it really doesn't even need to be an enlarging lens) have plenty of light fall-off when used open wide. So stop down at least two f-stops to minimize that problem -- unless you like lighter corners.

If you need the bright light from a wide open lens, just make sure you get the enlarger head WAY UP HIGH -- which kinda, sorta defeats the purpose. A light meter can tell you how much light fall-off you have.

[Mark Sampson]

Now that I think of it- 20 years ago when I played around with Azo, I took the lens out of the enlarger and let the cold-light shine directly onto the contact frame. That still led to minute-long exposures. With enlarging paper, that would be too bright. Have fun- Best of luck!

[Lachlan 717]

Longer exposure should be fine - allows a bit of D&B if required. Thanks!

[ic-racer]

Unless you need to use the dichroic filters of the enlarger, you might have a more even exposure across the paper with a lamp 5 or 6 feet away.

A sensitive method of checking even exposure across the paper is to expose the paper to the light without a negative.

[nolindan]

Ditto Mr. Racer. Cheap enlargers are crap when it comes to producing even light. Hang a bulb from the ceiling - good enough for Edward Weston.

If you want to go full luxe look for a nuArc contacting printing light. It's a point source, though, so dust will be a problem. The liight has a filter slot, unfortunately it is the wrong size for VC filters.

[monochromeFan]

Ditto Mr. Racer. Cheap enlargers are crap when it comes to producing even light. Hang a bulb from the ceiling - good enough for Edward Weston.

If you want to go full luxe look for a nuArc contacting printing light. It's a point source, though, so dust will be a problem. The liight has a filter slot, unfortunately it is the wrong size for VC filters.

if a person is contact printing LF or ULF, they should look at using an LED screen for the light source.

It was, maybe still a thing, but people were doing "darkroom prints" by taking a photo with a camera or cell phone, tossing it to grey scale with photo shop, and inverting it into a negative. And then putting a sheet of regular enlarging paper on the monitor in a dark room of course, and then turning the monitor on to make the exposure.

Also, you COULD get contast filter sheets to lay on the negative. That would not be cheap though. Have seen ultrafine or freestyle have an option to buy custom sized contrast filter sheet.