John,
I wouldn't think the fixer would cause the emulsion to turn pink. Could it be just the color of the base stock, I have seen tinted base stock before but don't remember seeing any in pink, its usually just a little brown like sepia.
In the past I have used Liford Ilfoline IN-5 for PC flim work but a few years back I attempted get more and couldn't find any. I did find that Freestyl Photo still has a fairly good selection of sheet films but the prices are bloody expensive these days. 25 8x10 Sheets of Ilford FP4+ is $102 about $4 per sheet. www.freestylephoto.biz
Tell me more aobut you photo plotter. I always wanted to build one but never had the time. What did you use for the drum? How are you doing the pixel timing as the drum rotates? Are you using a rotary encoder or just timing from an index pulse. What RPM are you running?
After I finish up my CNC mill project I want to build UV laser diode raster based direct PCB writer. Volkan Sahin has already done some testing with great results. This eliminate the film and photo plotting entirely.
Craig
--- In Homebrew_PCBs@yahoogroups.com, Jon Elson <elson@...> wrote:
>
> Hello,
>
> I just got a box of Kodak Polychrome recording film PRD on eBay for a
> steal. probably $100+ of silver
> in it, for $9.99 plus postage. I built a laser photoplotter years ago,
> and have had to recalibrate it for film a
> couple times as films became unavailable. I have almost used up my box
> of Agfa HTR3 film, which worked
> great, but Agfa is out of the film business, so I have to retool again.
> I get an image with this Kodak PRD film,
> but when I put it in the fixer, the clear areas turn quite pink! I
> called Kodak, they don't sell this stuff anymore,
> but somebody there said to dilute the fixer. I tried that, didn't seem
> to make any difference.
> I am using Kodak rapid fixer, not really designed for graphic arts
> films, but worked fine on the Agfa film.
> Anybody who works with litho film ever seen anything like this?
>
> My photoplotter uses a single 670 nm 5mW laser diode and some lenses to
> produce 1000x1000 DPI
> raster images at 0.6 inches per minute (raster lines can be up to 18"
> long wrapped around a drum rotating
> at 600 RPM.)
>
> If I can get this film to work, it looks like it will be fine for PCB
> master artwork, which I also use for solder
> stencils made from .003" brass shim stock. I'm just afraid that reddish
> background will interfere with the
> UV passing through the film.
>
> Jon
>