What's causing my spots?

[jmxphoto]

Ok, so I got a ton of Kodabrome #2 off ebay a while ago. It was a rediculously good deal, $53 for a 250ct box, 8x10. I've been using this as contact printing paper for a bit but now I'm trying to projection print on it and I'm running into problems. My exposures are around 6-10sec F32. At these settings I seem to be getting little light specs on my prints that get more diffuse if I go t 3sec F22. I'm thinking around F11 I should be good but that's obviously a miniscule time period that's not really usable. The dots aren't on the contact prints so it's not the paper.

The dots seem to be on the negs, I've dusted the negs, gently cleaned the neg, used compressed air to blow off the lens (both sides), and the condensor lens. The negs were processed months apart in different batches of Xtol, fresh fix, etc.

When I was checking the head for a hi/lo switch I noticed some pretty thick dust on the bulb (which is factory original actually!). Could that have caused it? I'm a little stumped. My only other thought is that maybe it's water marks on the back of the film that F32-22 renders too sharply. I don't know, I'm grasping.

Here's what my problem looks like:


That's about a third of the area of the 8x10. Please excuse my blah almost-macro work.

I think I'm going to try some different paper tonight and see what that yeilds, but I'd love some help. I'm a little stuck.
-James

 

[DWThomas]

Dust on the condenser or diffuser in the enlarger? To me, the fact that they get more diffuse with larger apertures suggests it might be such a condition.

DaveT

 

[jmxphoto]

I don't think there is a diffuser though it is a frosted 150w lightbulb. Should there be a diffuser if there's a condenser? I'll redust the condenser as well and see if that clears it up too. Are condensers especially delicate? Any cleaning instructions other than air in a can? Thanks for the help!

 

[jmxphoto]

I think you hit it perfectly! I took the condenser apart and there was pretty much a layer of gack all over everything. Compressed air didn't faze it, nor did a static brush so I used a mild glass cleaner (windex vinegar) and paper towels, then compressed air before assembly. It should be an order of magnitude better now. It almost makes me wonder how this thing was stored in its previous life!

Sorry for such a n00b question. This is the first darkroom I've put together. At least we have a great example pic of what a ton of dust on the condenser looks like! Thanks so much for that suggestion. It would have been a while before I took that apart.

 

[Anscojohn]

JMX,
I used to clean my condensors on a regular basis--about every ten years (VBG)

In ye olden dayz, it was considered important to ground the enlarger to a cold water pipe to keep static electricity from attracting dust. I guess, nowadays, most plugs are grounded, though.

 

[fschifano]

All that is good. Obviously, the smaller the aperture, the greater your depth of field (of depth of focus) will be. But you have another problem, and that is too much light. Either the lamp in your enlarger is oversized, or the thing was designed when slower papers were more common. You need to cut down on the light a lot so you can get at least 10 seconds at f/8 or so. That gives you some time for dodging and burning, and also lets you use an aperture where the lens is most likely to be at its best. First, make sure that the correct lamp is installed. Often, and mistakenly, a larger lamp has been fitted to the machine. This is not good on a couple of levels. First, it's too bright. Second, it can throw more heat than the machine is designed to handle. If the correct lamp is installed and you still have too much light, then get some neutral density gels from Rosco, cut them to size, and place them in the light path above the negative. I have an old Omega B600 that is just too bright, and that's how I solved the problem.

 

[Rich Ullsmith]

I would still rule out the paper by printing an 8X10 to mid gray, no neg in the slot, just to check. Contact prints are a little more contrasty, and plenty of black too, where your dots would not show anyways. It's cheap and quick to rule out the paper. With older papers, on occasion I find disparity (particularly in an open pack) between the top sheet and something from the middle.