Aging tungsten light characteristics?

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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

-- Chris Jordan (Boston) (postmaster@jordanphoto.com), June 06, 2002

Answers

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 (walton@ll.mit.edu), June 06, 2002.

That makes sense. Thanks!

-- Chris Jordan (Boston) (postmaster@jordanphoto.com), June 06, 2002.

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