Laser Printer RGB Filter - Color Test

<p>Several years ago I printed a set of RGB patterns on some overhead projector transparencies, mostly as a joke, to see if I could maybe get a color image out of black and white film, in the vein of Autochrome or Dufaycolor, only a lot less technically developed. I finally got around to running one over a sheet of ordinary black and white film (Arista EDU, 100 speed, if it matters) during some camera testing a few weeks back, and sent it in with my other film for processing.</p>

<p><br /> The process was simple, a basic 2x2 RGGB pattern copy-pasted until coverage over a full 4x5 sheet was accomplished, then printed onto the overhead projector transparencies. The pattern included registration marks for alignment. The overhead projector transparencies were then cut to the size of a 4x5 sheet of film, and placed facing towards the lens over the film in a standard film holder. Much cursing ensued during the placement of the film. Exposure was slightly extended to account for shooting through the overhead projector transparency.</p>

<p><br /> I scanned the negative with the overhead projector transparency facing the scanner optics. The registration marks turned out to be useless, as the cutting I did rendered the overhead projector transparency too large to fit in my scanner template for 4x5 properly alongside the 4x5 sheet film. I scanned this as a color negative, which my scanner software automatically inverted. I think due to the lack of a color cast in this film, the scan came out too red. I dropped the red level ONLY but a few notches, and I got the image below.</p>

<p><br /> Did that actually work? I have no clue. In real life, the blankets are blue, the dog is brown and white, and his eyes are brown. I see blue blankets, a marginally brownish dog, and maybe a brown eye? But I strongly suspect that is just processing artifacts. I'll try it a few more times with less blue and see what happens, but I think I'm just seeing things on this one. Anybody wanna try it and confirm I'm nuts? ;)</p><div></div>

<p>Well this is interesting.</p>

<div></div>

Huh. That looks a little more like color and a little less like random "noise" from the "filter." Thanks for tweaking that a bit. Now I really do need to try some more tests, just to satisfy my curiosity.

<p>Interesting idea. For your next shot try shooting a color checker so you can see if it's working at all.</p>

<p>You need a positive print to make this work. So make a contact print of the negative on another sheet of film, process that, and then sandwich with the color grid transparency. Scan as a positive.<br>

Alternately, you can sandwich the negative with a grid of Cyan, Yellow, and Magenta squares. Remember that those are the colors of the dyes in color negatives. (In slides as well.)</p>