showwx+ Laserprojector for pcb exposure - composite video quality issue

[Amper]

Hi!

im currently doing a few experiments trying to expose some dry film with a showwx+ miniature laserprojector like the one mikeselectricstuff has done a teardown on. The first test with the testscreen of the device itself has shown promising results, not the very best quality, but still the 450nm of the blue laser is sufficient for exposure and the lines are clear enough. However now i ran into a pretty pathetic problem: These things seem to accept only composite video. I tried with a raspberry as the source but with unusable results. I suspect that the problem is the signal source, no so much the projector it self.

Can anyone recommend a good source for composite video that allows me to show a single frame? b/w would be fine as only the blue will take effect anyways. I dont want to invest in some converters if they turn out to produce the same horrible quality.

Or does anyone know if there may be a different way of feeding it some other signal?

[Photon939]

I have one of the original Microvision Showwx projectors - if you poke around on ebay you might be able to find a VGA dock for it, I got one for mine. It allows for much higher quality video input.