Slide projector - discharge lamp light source?

Anyone aware of a make / model that used mercury or other discharge lamp light source for conventional ie 35mm photographic format slides, not scpecialised large format systems

Reply to
N_Cook
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I'm a bit lost, here.

Discharge lamps are not continuous-spectrum sources, and would probably not work very well when projecting color images. And with mercury, you'd have to filter out the UV, not to mention the ozone generated by the UV.

Reply to
William Sommerwerck

not

to

So am I, video projectors and back projected TVs seem to manage fine.

Reply to
N_Cook

They don't melt or burn like film does.

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Reply to
Michael A. Terrell

ve

Well, at the very least the 'image' can be electronically colour corrected to compensate for the uneven spectrum of the source. On the other hand, one probably only needs to to provide illumination in the

3 [or 4??] colour layers that slides use. I have not noticed any 'ozone' smell around mid-sized video projectors, so what's with that?

Neil S.

Reply to
nesesu

Do you need one or are you just thinking out loud? Are 35mm slides still popular? If you're not seeing them maybe the technology isn't calling for discharge illumination.

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Reply to
Meat Plow

Just curious. Just repaired a Kodak carousel projector with 300W bulb and wondered what the power requirement for a lumen for lumen equivalent discharge lamp would be , or is it just smps gives the edge. But then is there a problem with smps supplying a filament lamp, in the way of thermal runaway

Reply to
N_Cook

I think the technology is stagnant. Same goes for home movies on film.

There isn't sufficient need to improve the design.

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Reply to
Meat Plow

Agreed. Slide projectors never got past tungsten-halogen lighting.

Discharge lamps would no doubt be more efficient. But... not only would you have to correct for color balance, but the bulb would have to be "mated" to the projector's optical system.

Reply to
William Sommerwerck

Large theater projectors are still an arc light ? There must be some sort of white/color balancing scheme for them. Same could be used on other forms of HID illumination.

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Reply to
Meat Plow

I'm not sure. I seem to recall that some use some form of tungsten lighting. Don't hold me to it.

The "scheme" is simply to have a standardized color temperature. The prints can then be balanced accordingly.

Reply to
William Sommerwerck

They're used for lighting on film and TV so can be pretty good. As well as for DLP etc projectors.

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Reply to
Dave Plowman (News)

On 3/1/2011 9:25 AM William Sommerwerck spake thus:

Nope; xenon arc. Like this:

formatting link

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Reply to
David Nebenzahl

I seem to recall that modern cinema projector lamp houses make use of short-arc xenon discharge lamps, but as you said, don't hold me to it ...

Arfa

Reply to
Arfa Daily

Speaking of HID lights, does anyone know where I can get a schematic for a Philips EUC 120 C/00 Lampdriver?

Thanks, tm

Reply to
tm

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