Eee Gads! My new enlarger leaks light...

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Hi all,

I am starting to play with my new enlarger in my new household darkroom. I have the Saunders/LPL 4550 XLG with VCCE head. I was surprised to see a lot of light leaking out of the negative carrier slot "painting" a thin line of light with a 270 degree arc along my walls perpendicular from the verticle axis of the enlarger.It is really quite bright. There are some other small light leaks around the heat shield for the bulb which also project out horizontally. I can't see anything projecting down toward the paper.

So here is the question:

Is there a problem with light shooting out like this? I do have black cloth hanging on the nearby walls where the light band hits, so I don't think any is reflecting onto the easle.

If there is a problem, then what to do? Perhaps a cloth skirt with elastic around the negative carrier slot to block the light?

The small light leaks at the heat shield aren't aimed at the easle and I think any cover-up there might get too hot (ie: catch on fire).

Any and all advice as to whether this is a problem and solutions if needed would be welcomed. Seems odd to design an enlarger with light pouring out of it...

Scott

-- Scott Jones (scottsdesk@home.com), June 02, 2001

Answers

As long as the walls where the light is striking are not white and reflecting light back on to the easel, you are probably OK. You can ease your fears by doing a fog test. Put the cap on the lens, put a piece of paper in the easel, turn the enlarger on for 5 minutes, then process this piece of paper with one straight from the box and see if you can detect any fogging by comparing them.

-- Steve Baggett (sbaggett@midsouth.rr.com), June 02, 2001.

Welcome to the wonderful world of Saunders.

No it is NOT alright to have light leaking from the enlarger. Get yourself some black velvet cloth and tape it to the enlarger creating "curtains" where the light is leaking from. Do not place the cloth tightly over the air vent, just drape it enough to block any light leaks.

The Saunders is a good enlarger, but little engineering design went into the light seals.

Enjoy it as it will produce wonderful images.

Bill

-- Bill Smithe (bs2@aol.com), June 02, 2001.


Scott,

I don't think you will suffer any ill efects from this. As noted above, do a simple test to see if there is any fogging, and then take the appropraite action if necessary. Enjoy.

-- Jim (jimzpace@yahoo.com), June 02, 2001.


John Sexton uses this same enlarger (or at least he did at the last workshop in his studio that I attended about four years ago). He has several home made devices for stopping light leaks at various points with this enlarger, one of which is the skirt that you mention. If you really want to get discouraged, put your head on the easel and twist around so that you can look up into the lens and lens carrier with the light on. What you see is what your paper is seeing when you print and you may see a lot of light leaking from around the lens board and therefore onto the paper. To stop extraneous light from that source I've fashioned a gizmo out of carboard that attaches to the two screws that hold the lens board in place on my Beseler MXT enlarger. I disagree with those who say that your light leaks aren't important. Everything has a cumulative effect in the darkroom and that light leak, combined with your safelight and perhaps other seemingly insignificant light from other sources, can all add up to a problem. Rather than trying to guess whether it's a problem, I'd try to fix it and not have to worry about it.

P.S. Saunders isn't the only enlarger that has light leaks out of the box. I've used Beseler and Omega enlargers, plus seen the Saunders. All had light leaks from several sources. Maybe Dursts are different - I've never used or seen one of those. Finally, the way I was taught to check for light leaks from the enlarger is to turn off all the lights, sit in the dark for 10 minutes, then turn on the enlarger light with the lens cap over the lens and look all over, under, and around the enlarger.

-- Brian Ellis (bellis60@earthlink.net), June 03, 2001.


Scott,

Just do a simple test for fogging as Steve suggested above. Think about it. Just think how much light is hitting your paper when you are making an exposure and how you can have pure(non fogged)white areas right next to pure black in a print. Just do the test and determine if this is a variable for YOU or not. Please let us know your results :) Most importantly, have fun!

-- Jim (jimzpace@yahoo.com), June 03, 2001.



John Sexton's enlargers do indeed still have mini-skirts. The correct fog test however is to get the test paper preexposed to a very light grey then block off 1/2 of it and expose to ambient light from the lens capped enlarger and more importantly your safelight or do two teast one for the enlarger and one for the safelight conditions. I was shocked when I saw my safelight results. As a result of the Sexton course I painted the walls adjacent to the enlarger flat black, screened any light leaks from my enlarger and redirected my safelights to bounce. George

-- George Nedleman (gnln@thegrid.net), June 03, 2001.

If it's any comfort, Beselers do the same thing. Mine is in a three sided booth sort of arrangement and the walls are painted flat black so the leaking light does not go any where.

The suggestion about doing a fog test with a prefogged piece of paper is a good one. You have to get the paper over its threashold to do a valid test.

-- John Hennessy (northbay@directcon.net), June 03, 2001.


Most enlargers have an amazing number of leaks.

Cover any ventilation holes that leak light with foam air-conditioner filter material; it's porous enough for good airflow but will block light.

I've used foam weatherstrip material to to seal the bottom of the enlarger head against the neg carrier. This was of course on an enlarger in which the head is lowered onto the carrier. Don't use foam on the bottom of the carrier.

-- John Hicks (jbh@magicnet.net), June 03, 2001.


Scott, Excellent choice of enlarger! I bought my LPL used and it too leaks as you describe. I remedied the situation thus: painted the walls around the enlarger matt black (the wall on the bulb side of the enlarger is only 8 inches from the head!). I then used small sections of black mounting board to form a box around the enlarger casing that covers the bulb. I fixed the card panels using tape and voila no more leaks! By the way, I ran some tests and before attaching the panels my printing paper showed no visible signs of fogging...but I fitted them just to be on the safe side! I haven't a problem with light leaks from the negative stage, maybe you need to fit some card/foam shims so that when you lower the negative carrier handle to clamp the carrier in place, the gap is lessened. Run some tests and if there seems to be no effect then I wouldn't worry, however if there is any sign of fogging then use some/all of the suggestions mentioned by previous contributors to the forum. Best of luck Paul

-- paul owen (paulowen_2000@yahoo.com), June 04, 2001.

Scott: A few observations and suggestions...do test. I think you'll find it doesn't make any difference. But if it does, I have found a 3M product very handy for totally stopping light from seams/joints which don't need to move. It's called autobody clay and it is black clay used in autobody work to fill joints. It comes in strips about 1/8" wide. It was very useful to stop massive leaks when I converted a B22 to a cold light. It scrapes off easily, which is more than I can say about silicone sealant. It really sticks to anything. For light skirts as discussed in previous posts, bicycle handlebar tape is very useful. Lots of these are adhesive backed on just one side of the tape, so they make good light skirts if you put them on just right. If you put it on just right, the unstuck side toward the negative carrier, for example, it will just touch and shut out the light without enough being there to fold under and cause a fit problem. Finally, painting the darkroom walls, ceiling, etc. makes sense but if you're enlarging wearing a light colored shirt the biggest source of stray light is you, because it reflects off you and you're the one standing right over the paper.

-- Kevin Crisp (KRCrisp@aol.com), June 04, 2001.


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