Results of leaking enlarger tests

[scott jones]

As many asked from my last post about my Saunders/LPL 4500 XLG enlarger leaking light(http://hv.greenspun.com/bboard/q-and-a-fetch-msg.tcl?msg_id=005NaN), I am posting my results from tests that I have just run.

My safe light (Patterson orange tabletop dome light 15w) tested safe even at ten minutes at 6 feet away (I process prints in a JOBO so my paper is exposed for o nly the time of the enlargement exposure; no trays). I was using Polymax Fine Ar t DW FB glossy paper pre-exposed to a light gray of approx Zone VI-VII.

I then put the lens cap on the enlarger and ran the same ten minute test on a pr e-exposed piece of paper with the safe light off but TONS of light spilling out of every conceivable crevice of my enlarger. I have black velvet on the walls in the corner that I use for the enlarger so there is no wall bounce, but after my eyes got used to the dark, I was amazed at how much light was hitting all aroun d my easle. I could easily see my hand with great detail. I could just make out the coins that I placed on the paper for incremental testing on this piece of pa per. I also tried to do the worst case scenario by having the enlarger head way down close to the paper. I was sure that my test would be very positive by the l ooks osf all of this.

To my great surprise, the print showed not a trace of fog from all of this light . My conclusion is that at least in my situation, it looks like I don't have to spend any time making "miniskirts" for my leaky enlarger (actually I'm quite rel ieved; this seemed like a big pain to me). My thoughts are that enlarging paper is slow enough that this type of light is insignificant. So as many of the peopl e who responded to my previous post hinted at, it may not make any difference wi th the leaks in this enlarger unless you have a direct bounce off a wall or obvi ous light hitting the paper. Light falling outside of the paper doesn't seem to have any effect at least in my case.

Any comments are welcome and I posted this in the spirit of feedback to all thos e who responded with prevoius comments about light leaks in enlargers in general ...

Scott

[Charlie Stracl]

Thanks for sharing your results.

I've never detected any problems from light leaks, but that doesn't mean they can't cause problems.

[Jim Billlups]

Scott,

Thanks for the update... This is valuable information. Now we want to see some of your work Have fun with that new enlarger!

[Nicholas Fiduccia]

Scott,

Did you dry the paper before evaluating the results? Fiber paper usually dries down darker than when it is wet. Thanks for sharing this!

Nick

[scott jones]

Yep! Dried paper still shows no signs of fogging.

[paul owen]

Scott, If your tests prove ok then I wouldn't worry about the light leaks, BUT, I do second the advice on your previous thread about wearing light coloured clothes when printing. I wear a red t-shirt after realising that the white one I used to wear seemed to "illuminate" the easel.Whether this had anu effect on the paper, I'm not sure, it was just a little disconcerting! Hey, who knows, maybe we could market red darkroom t-shirts!!!! Regards Paul

[Chris Ellinger]

Thanks for posting your test results. I use the same enlarger. Do you use the masking attachment that goes under the negative carrier? That thing leaks a lot light. I took mine apart and painted the underside flat black. Seems to help a bit.

[paul owen]

Scott, I received the negative masking stage and the glass 5x4 neg carrier that I ordered this afternoon, and have just finished some prints. The glass carrier makes a real difference in keeping the film flat, especially 6x9 negs that for some reason didn't want to lie flat. But the masking stage does leak a hell of a lot of light at its edges. I have had a quick look and I think that I will need to add a few strips of weatherseal type foam strip. The light is escaping through the slit that allows the masking blades to travel and is spilling over the frame. A real pain in the ass!! The stage just cost me #100. Still, a little DIY and it should be right (fingers crossed) I ran a quick test and there doesn't appear to be any fogging, and the prints are great, but its still a bit offputting when these beams of light are illuminating my darkroom!! Regards Paul