Home made 8x10 enlarger questions

[Paul Ewins]

I'm just kicking around the idea of making a simple horizontal 8x10 enlarger. The maximum elargement will probably be 16x20, but allowing for possible cropping 3x seems to be a reasonable limit. At 3x enlargement what will be the approximate distance between the lens (say 300mm) and the negative?

At this stage I think I'll probably have a simple overlapping box arrangement to provide most of the extension and rails and bellows from an old speed graphic to provide the fine focus.

OK, now for what is probably a stupid question... Is it possible to use a flash as the light source, say something like a Metz 45? Or a couple of them, as they are cheap secondhand. I've heard of pulsed Xenon heads and that set me wondering. Admittedly, it would be difficult to focus but there may be ways around that.

[Turner Reich]

Why not use some banks of LEDs for the light source? And yes a horizontal enlarger is very do able. Sounds like you have given some thought to it. I don't know about the flash though.

[Brad Rippe]

Paul,
I like the idea of a homemade enlarger. I was considering building a simple two box 8 by 10 system as well. I'm not sure about the flash idea because it seems it would be difficult to dodge and burn with a flash, or even a series of flashes. LEDs or conventional incandescent might be a better way to go. I think it possible to have the two boxes slide past each other if lined with felt, and there wouldn't be the need for rails or gears etc. For the negative carrier would you compromise a film holder by cutting out the center panel? Good luck and let us know how it goes.

-Brad

[Andrew O'Neill]

I tried the LED route but the most contrast I could get was the equivalent of a grade 4 paper. That was with Ilford MG IV FB and Forte Polygrade V FB. I am quite satisified with an Aristo 1212 with V54 tube. I can get just under grade 6 on both papers.
I've never tried a flash. If it does work, you can still expose your paper in bursts and it is possible to dodge and burn with short blasts. I use a burst system with the 1212. I learnt that method from Fred Picker.

[Paul Ewins]

Apart from the (probably silly) flash idea, I was leaning towards compact fluorescent bulbs as a light source but will have a look at short tubes too. I have read Huw Finney's LED enlarger webpage, but the electronics look beyond my scope and scaling it up to 8x10 looks to be a prohibitively costly exercise at this point in time.