Thread: Inexpensive Over-volting of Tungsten Sources?

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  1. #1 Inexpensive Over-volting of Tungsten Sources? 
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    Was thinking of ways to get more out of practicals and was wondering if there were any inexpensive ways to overvolt the hell out of off-the-shelf tungsten sources... Like 220volts or even higher, to try and take them from ~2800 to ~3800 and increase their output in the process. In theory it'd be great, as then when you use 80c or 80d filters (to get them even closer to daylight) the added output would supplement the stop-loss...err light loss... from the filtration.

    Is it generally bad practice? Does it blow fuses or set houses on fire or something? Are there easy to find (and cheap) transformers that don't hum to beat the band?
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  2. #2  
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    You can do it as long as you know what you are doing. I do it all the time

    By increasing the voltage (and the current) the longevity of the bulb would go down, the colour temperature will increase and the luminous output will go up as well as efficacy. But, if you over-do it...the longevity may go down to a fraction of a second :)
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  3. #3  
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    Cheap no, but a Variac has a boost setting of 120% I think. 220 will pop any (110) tungsten globe instantly.

    http://www.parts-express.com/pe/show...m_campaign=pla

    Nick
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  4. #4  
    Senior Member Eric M Hurt's Avatar
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    Seems like a lot of work and a big pain in the a*s instead of just getting a larger bulb and a few more amps............
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  5. #5  
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    Bahhh, 120% (as in a 20% increase only?) isn't worth it... especially if the bulbs blow at anything higher than that. Needs to be a pretty huge increase to see a substantial difference, and as Eric suggested, it'd be easier (and probably cheaper) to just get better, brighter, whiter bulbs...

    Pawel, can you give specifics as to how (and how far) you push your bulbs?

    Thanks for the input.
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  6. #6  
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    I use Osram HPX globes, which are already stressed to different degree depending on the model. Some are only rated to 15h burn time.
    If you increase the voltage, the current also goes up, so the output increases expotentially. We are only talking up to 10-30% increase in voltage depending on the specific lamp.
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