Film-Tech Forum ARCHIVE: HELP i need a pair of Solar Cells

This is topic HELP i need a pair of Solar Cells in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Marin Zorica (Member # 1716) on 03-12-2004, 05:48 AM:

Hello!!!!!!!!
I know that everbody using solar cells for reading analog sound from film, but here in my contry situation is not so cool, becose on mostly projectors insteed solar cells the photodiodes are instaled (they are 1PP75 made by tesla in polish, or BPW 34 made by siemens that i using in projectors becose they are smaler than 1PP75) also we using exciter lamps.
I saw solar cells and work with them only in theters that buy that, in my local theater i also want to upgrade sound from mono to stereo but when i get a price of cell from dealers here the price is 200 - 300$ for each, but that is to expensive becose for pair of cells i can buy a CP 50!!!!!!!!.

Now, if enebody got some old cells, dusty or dead procesor or anything that can help me with upgrading soun please tell me, expecialy if you are from europe, you don't need to give me for free (even i like to someone give me a old cell, or something for free [Smile]

), you may sold to me for some price, becose i want to upgrade sound but the prices of eqipment here is so high that i can't buy that.
The amplifiers and speakers for system i made by my own ( i alredy made a 2 stereo aplifiers for that).
If someone have enytnig let me know.
I also have one more question, on forum i saw people talking about some cyan tracks, what is cyan track, and what for we need a led readrs insteed exciter lamps for that????.

Posted by Steve Kraus (Member # 476) on 03-12-2004, 07:25 AM:

On color film the image is formed of chemical dyes formed during processing, the silver having been removed. The dye image is almost completely transparent to infrared (IR) light and unfortunately IR is the strongest portion of the light put out by a standard incandescent light bulb such as an ordinary exciter lamp.

Thus, the major portion of such a light beam will pass through a color film without being modulated (regulated) by the soundtrack.

This is not the case with B&W film where the image is silver nor on the Technicolor dye transfer color prints which actually start as B&W and also have silver soundtracks.

To avoid this issue the film laboratories do something called "application" where a special processing fluid is rolled or sprayed onto just the soundtrack area. This special treatment causes the silver to retained in the soundtrack so that it can be read with a light beam that is mostly IR.

The film labs would like to end this as it is awkward and is the cause of much waste such as when the special developer splashes into the picture area or is not applied evenly.

The replacement will be a track made of dye only without silver and it will be in the cyan layer only. Thus, it must be read with a red visible light source.

Without the red light source the cyan track will be barely audible.

Posted by John Pytlak (Member # 331) on 03-12-2004, 09:44 AM:

Kodak has technical information about silverless soundtracks on its website:

http://www.kodak.com/country/US/en/motion/support/dyetrack.shtml

Lots of additional information and links on the dyetracks committee website:

http://www.dyetracks.org

Posted by Jean-Michel Grin (Member # 1360) on 03-15-2004, 08:40 PM:

Hi Marin !

Do You need stereo Cels for Your projector ? I have a lot for sale ! (but that depend from my boss authorisation) What kind of brand of projector that You Use ?
Recently I modified various Simplex's sound readers for Dye tracks reading, and maybe my boss could seal to You somes part (sorry for my weak English :-) ) BUT: for Dye track compatibility whith a direct Scan sound reader You must buy a Red light source. I don't remember the brand name but I can search It for You if You give me the Brand Name of Your soundhead.

If You're interesed just send me a private Email and I can Ask to my boss for a price for stereo cells.

Nota: We got Dolby CP 50 and CP 55 for sale too !

Bye,