Testing for Enlarger Lens Flare

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Greetings, I would like to rule out enlarger lens flare as a darkroom problem. Does anyone know of a way to test for how much if any flare I am getting with my current setup. Thanks Keith

-- Keith Baker (doublehall@aol.com), March 13, 2001

Answers

Keith, Flare on printing stage is easily detectable on high contrast borders. If you print, for instance, a heavily dense negative showing part of the blank border, it might be obvious some "bleeding" from dense areas of the print. Another simple test, if you have a good lens, is printing detailed shadows while looking for resolution on near black densities. Flare is a killer of details on these situations.Good luck. Cesar B.

-- Cesar Barreto (cesarb@infolink.com.br), March 13, 2001.

A few ideas, if your lens is a concern, then I assume it's not a top drawer recent model from a major manufacturer. Borrow one of known high quality and compare prints. Don't underestimate how much light leaks out of the enlarger through the top of the cold light, through the gap between the lens stage, below the negative carrier, etc. If you're wearing a white shirt you'd be amazed, this can fog the paper a bit. Turn off the safelight and turn on the enlarger and check this out. Also, make sure your negative is properly masked, with no bright light coming out around it on the easel except where you want it. That spill over can bounce off just about anything like your magnifier, etc. and affect the print. Generally speaking, this isn't much of a problem, even with lenses dating back 30 years. If you're seeing something and you have a good lens that isn't all scratched up or fogged, it could well be something else.

-- Kevin Crisp (KRCrisp@aol.com), March 13, 2001.

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