Elwood 8x10 modifications

[MTGseattle]

Since LFPF site is being bogged down I figured I would ask this over here.

My floor anchors for my Elwood column failed. (user error) and the working height with the thing sitting on the floor would have had me printing on my hands and knees I decided to tackle a side quest during my get the darkroom working again mission.

I have the Elwood mounted on the wall now, and I have a test led light source arriving today.

Question #1
Is there an optimal distance between light source and negative? In its "normal" form and using an Arista 1010 cold light, there was approximately 3 inches between the diffusion panel and the negative.
The diffusion panel in question is white acrylic that is 3/16" thick and was mounted to the posts that I guess held the original Elwood glass pieces.

Question #2 the diffusion panel is shiny on both sides. I would think that this is not ideal, but maybe it doesn't matter? I'm asking because I was thinking of using it again rather than driving across town to get a textured piece.

Question #3 can Newton rings occur regardless of light source type?

Not exactly a question #4 My thought as far as evaluating the diffusion panel was to take a given light source and incident meter that then take a reading of the same light shining though the diffusion piece. I figure if it's more than 2 stops different, I'll get a thinner piece.

 

[koraks]

Is there an optimal distance between light source and negative?

For enough for even illumination, not further than that because you just lose light. Other than that, doesn't really matter much - assuming a diffuse light source. For a condenser setup and/or point light source, different story altogether of course.

Question #2 the diffusion panel is shiny on both sides. I would think that this is not ideal, but maybe it doesn't matter?

I've worked with diffusers with shiny sides and never noticed any issue.

Question #3 can Newton rings occur regardless of light source type?

Yup. Newton rings are a function of two fairly smooth surfaces on top of each other. I can sort of see how they might be more or less apparent depending on a light source difference though. However, a diffuse light source does not make a setup immune to Newton rings.