Aging tungsten light characteristics? : LUSENET : Large format photography : One Thread

I'm noticing a dramatic increase in contrast put out by my tungsten bulb, combined with a decrease in intensity. Given the age of the bulb (2+ years), its a matter of time before it blows. Does anyone know if tungsten sources begin to shift toward "magenta", or know what exactly is occuring in the aging process? Just curious. Thanks,


-- Chris Jordan (Boston) (, June 06, 2002


When it is time to change the bulb in your enlarger, it does have a tendency to shift to the red/magenta side. At work we have a system for all enlargers to talk with each other called the R System. We monitor everyday due to the differences everyday.... Chris, we change bulbs sometimes every 4 months due to the R values drastically getting different. As the bulb burns out it will get warmer (going to the red spectrum). When this happens, you will be fighting a loosing battle with no consistency later when reprinting if you keep track of your color numbers. Get a number of bulbs and have them on hand.

-- Scott Walton (, June 06, 2002.

That makes sense. Thanks!

-- Chris Jordan (Boston) (, June 06, 2002.

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