Topic: Anyone made a UV exposure box for alt process printing?

[grit]

Thought you all would be the right group to talk to for this.

Maybe 4-5 times a year, I get a wild hair up my nose to make platinum prints. The California summer sun is reliable, but the winter sun is not, so I am therefore considering building a UV exposure box. I have roughly the same amount of electrical knowledge of a 12-year-old, and have soldered something probably 3 times in my life, but I'm also somewhat motivated.

I found these instructions; they seem reasonable, but I will consider any and all alternatives. I'm hoping not to spend a lot of money, so the box just needs to end up functional, not necessarily pretty. I'm also willing to consider commercial solutions as opposed to building my own, but everything on the market seems like overkill for what is basically a once-in-a-while hobby.

Anyone who has made a UV box or has other relevant experience: is there anything I should be aware of before embarking on such a project?

[Francois]

I haven't made one but I think you should check out Mat Marrash's youtube channel. https://www.youtube.com/watch?v=klr2Sk_XCgY&t=1s
He made one using off the shelf parts from Amazon. If you can plug connector A in plug B, you can do this.
While he doesn't do this, I would suggest repurposing an old drawer for the box. Minimal carpentry.

The important thing is the wavelength of the light. And it turns out that black light leds are just in the proper range for a lot of alt. printing processes.
I don't know how well they would work for platinum, but it's easy to find out. Here's a blog post on just that https://www.timlaytonfineart.com/blog/2020/3/how-i-updated-my-uv-printer-for-platinum-printing-with-led-lights

[Pete_R]

For doing cyanotypes I used to use one of these face tanning lamps. They can usually be picked up cheap on local advertising sites where people have bought them, used them once and then sell them.

[grit]

Interesting! Thanks for the link Francois, that does seem easier than the Emulsive version. I bet IKEA's odds-and-ends department would have something I could repurpose, like an odd drawer or some kind of box.
 
Pete, I'm surprised that kind of lamp worked. Did you get decent results? How big a print could you make?

[Pete_R]

Pete, I'm surprised that kind of lamp worked. Did you get decent results? How big a print could you make?

Why the surprise. Tanning lamps use BL tubes which are the shorter wavelength types compared to BLB lamps and so are actually better for alt processes. In the Tim Layton article Francois linked to he says he used BLB lamps but in John Barnier's 'Coming into Focus', a sort of bible of alt processes, he says BL lamps are the ones to use and that BLB lamps put out much less UV and are more expensive.

I got excellent results with the tanning lamp and pretty short exposures (long time since I used it so don't remember exactly). I only ever printed up to A4 as that was the largest negative I could make but the tanning lamp easily covered that. I just used a cardboard box to support the lamp above the paper. Very simple and cheap.