Simple UV exposure box question. Are these the right lights?

[Candlejack]

So the title pretty much has the question in it.
Are these the type of lights one would use to make a UV exposure box?

 

[Vaughn]

They should work, but a lot will depend on the processes you are using.

 

[Candlejack]

They should work, but a lot will depend on the processes you are using.

Ill be looking to use cyanotype and van dyke. Im realizing now these light strips arent the SMD 5050, but the lower powered ones. What do you think, pull the trigger on these or just go with smd5050?

 

[Candlejack]

They should work, but a lot will depend on the processes you are using.

A5 paper size will probably be the largest ill work with.

 

[Nicholas Lindan]

Cyanotype is most sensitive to 320-360nm, but there is still a response at 400nm. If a shorter wavelength selection is available I'd take it. Otherwise, these should work fine.

 

[Vaughn]

Cyanotype is most sensitive to 320-360nm, but there is still a response at 400nm. If a shorter wavelength selection is available I'd take it. Otherwise, these should work fine.

I'd like to get down to 365 or so for carbon and platinum. But I found this interesting:

"Light sources that emit most of their radiation at long wavelengths of 400nm and above give images of higher contrast than sources that emit a greater percentage of their energy at wavelengths below 400nm." -- Sandy King, https://unblinkingeye.com/Articles/Light/L2/l2.html

So you might see some differences in contrast based on light source/wavelengths -- and also a small change due to changing the length of exposure (less self-masking with short exposures).

 

[Patrick Robert James]

I used some similar to those when I built a UV exposure unit. I packed them together tightly and with negs from my Canon pigment printer I get exposures with cyanotype between 1:30 and 3:00 with most falling in the 1:45-2 range. It took forever to solder them together though. Plus I added a different power source and computer fans. Probably neither was necessary. That was about two years ago. If I did it again I would get the light bars that everyone seems to be using. You probably won't get the super fast times, but it would be way more convenient to make. Get as many as you can fit in the box you want to use. No point in trying to save a few bucks because that will cost you time in the end. Only having to wait two minutes for an exposure was a complete game changer for me. My other advice for you is to build it as big as you think you will need so you will only have to build it once. I wish I would have made mine a little bigger so I could print from 17" negs If I get one of those printers but for now it works fine with 13" negs so it isn't too much of a loss.

I can go dig up the UV strips I used if you want to know what they were, but like I said, the bars would make things much simpler.