Projector Light tricks

[P3D Gabriel Jacob <jacob@xxxxxxxxxxxxxx>]

Sandman writes

>Part of the problem with projecting slides is the deterioration of the
>slide.  Well here is a newby suggestion.  Why not filter out some of
>the worst stuff before it hits the slide:
>
>We already heard 'bout the polarizing filter before the slide.  Cool
>reduce everything by 60%.  Well how about adding an inferred blocking
>filter (reduce heat) like the kind found on ALL CCD cameras?  
>Also, how about UV blocking filters like the kind that are on my
>glasses (or even just a thin plate of a blocking material like
>High Index Plastic)? UV eats the color and it is cheap as hell
>to block most of it?
>
>Any slide projectors out there already modified?

There was some discussion about these aspects a few weeks ago.
Most if not all projectors do have a heat absorbing glass in
them. What was concluded was that, this element of the projector
is probably one of the most crucial in protecting the slide.
In one of my recent fooling around projects I tried simulating a VM
stereo projector. In it I included a heat absorbing glass. The
details were posted recently. I realize you joined P3D recently (and
welcome to the club). I don't think Bob or John have put the recent
digests up on their server yet as these were quite recent, but I could
email you the recent digests if so inclined. 
BTW, CCD cameras as you mention include a IR filter. Over the holidays
I bought a Tyco VideoCam. This was bought against the advice of some
P3D members. They had some very good points, but I bought it for 4 
reasons. First it has dropped down to $36US(at Costco in Canada)! Second
I can take out the electronics and CCD and make it much more compact.
Third there is no IR filter to keep cost down on the cheapo video cam
and the optical lens can be easily taken off, so that it can be converted
into a pinhole or by replacing the cheap lens, dramatically improving
the clarity. Fourth, in 20 years it will be a collector item, among the
young tykes of today, looking for something from their childhood. ;;-)

As I mentioned, it doesn't have a IR filter, which makes it 
respond very well to viewing in the dark. I put a Kodak Safelight No.11
filter over a halogen lamp (the kind without the heat absorbing filter)
and was able to see in the dark very readily with it. I had some
photos and lithos on a wall and the photos were gray (absorbing IR?)
and yet the litho print was as very viewable. The CCD is gray scale and
has to be connected to a VCR for recording. 
I tried putting a beamsplitter on it but that didn't work very well.
When I take off the lens, will try it with other combinations.
Maybe ultimately it can be made into a 3D see in the dark camera. ;-)
Or maybe if mounted on to a train set or radio control car with wireless
video transmitter, it could be driven from a first person perspective.
Now think of that, 3D, see in the dark, first person perspective radio
control car or train set. It boggles the mind. (I am joking here folks.)

Also I connected it to a video wireless transmitter, my kid and I had
a riot when we secretly planted it in the washroom. Boy was my wife mad
when she saw it! ;;;-) Sorry I didn't tape it or have pics on the net of it.

Gabriel





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