Enlarger for slide projection?

[djmx]

Hello,

It is possible to use a 35mm condenser enlarger with projection lenses, UV/IR filters, cooling system and a more powerful light source to make a DIY slide projector? :confused:

It would be feasible?

Thanks

[Greg Lockrey]

The issue would be brightness. Projector lamps are very bright with strong fans to keep them cool. Enlargers for the most part aren't very bright past a couple of feet.

[djmx]

And changing the lamp and the ballast for a more light output?

[Greg Lockrey]

As long as you can find a way to keep the negative cooled down. I would think it would be cheaper to find a used projector.

[Lightbender]

I think the OP was intending to project larger than normal slides, such as 4x5, 6x17, 5x7, maybe even 8x10.

What about using an overhead projector? It may need to be modified with a prism and a better lens though.

[rmmx]

como te fue con este proyecto?? pudiste?

[Drew Wiley]

Large projectors actually existed at one time, and I suppose one might stumble upon
a used one, but refurbishing something like this might prove a problem. With enlarging heads, you have to be careful to distinguish the burning position of the lamp. Bright lamps like halogens have a certain angle they are specified for, and not
just any voltage is available for every application. You need to check with a specialty
supplier. Also, the diffusion boxes, filters, and wiring in an enlarging head might not stand up to continuous heat. You can increase your cooling fan capacity, but still enough heat and UV might get through with a powerful bulb to cause damage and maybe even fade your transparency. I once had a Durst color mural enlarger which required a 10-amp 220-Volt fan. Combined with the lamp output, which needed ground parabolic quartz mirrors to withstand the heat, this machine doubled my monthly electric bill ! Needless to say, I had to vent the heat outdoors with expensive 100% silicone ducting.

[hiroki]

I am thinking about building a large format slide projector myself. Because of the heat issue with bright lamps I was thinking along the line of an LED light source. Like LED floodlights. I thought maybe my Technikardan could serve as a projecting device (big black/dark box with a film holder and lens). Basically I could use any of my lenses depending on what scale I want to project. The only work (at least I imagine) would be to cut a film holder to let light through from behind and building an adapter from the rectangular LED flood light to the back of my Linhof. Either as a bag with soft material (may be easier) or wooden/plastic or some other hard material.

Anyway, the problem with the 35mm slide projector/enlarger, I think, is that it's made for 35mm size film. Even with further distance from the slide and a brighter lamp I would still imagine that there's quite some light fall off towards the corners. I'd think that it's made to lit 35mm evenly, but by far not 4x5 or bigger.

[tgtaylor]

Noblex - I think that's how it's spelled - manufactured 4x5 projectors in the late 1990's and sold at B&H for $3000. Although I haven't been on the lookout for one, one did pop-up on ebay a few years back for $2000. It didn't get any takers: The seller was located in Europe and had a feedback rating of 1.

If anyone needs 4x5 slide mounts, I have a couple of hundred of 4x5 Blair mounts I can sell: $25/hundred + shipping.

Thomas