It is possible, but not likely, that the lamp is the problem. I would suggest that the OP checks the following:
Originally Posted by paul_c5x4
1) Lamp (because it is the easiest thing to reach and/or fix)
2) Lens for fogging, fungus or haze. If the lens is dirty on the outside, use pure ethanol or propyl alcohol with a lens cloth to wipe it clean. If on the inside, it should go to a technician.
3) Check whether your light source assembly is properly aligned, all the lenses, diffusers, etc. are in their proper positions.
4) Make sure that your safety filter hasn't gotten stuck in the light path. This happened to me, and it took me a while to figure it out, I am embarrassed to admit . Okay, in defence, it was when I was starting out anew after a fifteen year absence. The lever that swings it out had disengaged, so I couldn't figure out how to get it out of the way until I opened it up and did some corrective tinkering. BTW, if you print on VC paper, then do not use the red safety filter in any event as it may not be safe for your paper. VC paper requires an orthochromatic (green-brown) filter. This at least is how I have it from my limited research on the subject.
My bet is 4, then 2, then 1 then 3. Let me know what you find .
Edit: I should have added that my enlarger is a Durst M605. It cannot be much younger than your L1200, so I do not think the filters are too old, unless the enlarger was standing in sunlight and the plastic has been UV damaged. Your L1200 probably has the same red safety filter that my M605 has. It can be removed without too much fuss. It is a bit like a gall bladder - one can live without it if one has to.
Last edited by dorff; 02-25-2013 at 07:36 AM. Click to view previous post history.