Topic: UV light sources

[DonkeyDave]

For Alternate Processes, I have a lack of sun....

Has anyone tried using Metal Halide Gro-Lights? There is a huge industry that has grown up over the last few years which basically seems to enable people to grow Hash in their attic. I've been looking at plans for using black light tubes, using industrial lighting metal halide, but they are all at least 3 times as expensive as using gro-lights which are more or less 'plug and play'. Most of the info on the net is US based, where there appears to be less interest in Grolights than the European side. Anyone tried it.
The kits come with ballasts, and variable reflectors to provide even lighting and stop hot spots, it would seem perfect for Alternate UV dependent processes - anyone tried it?

[Pete_R]

I believe grow lights actually have relatively small amounts of UV. They are designed to emulate daylight so most of the output is in the visible spectrum. You need UV light.

A cheap source is usually a second hand facial tanning lamp (like this one). That's what I use.

[DonkeyDave]

the sodium lights are daylight replicas, but the metal halide lamps (according to Sandy King) work well, he uses a large industrial metal halide type light, but they are quite expensive

[Andrej K]

As I mentioned in the email, I am using a philips facial tanner - http://www.philips.co.uk/c/light-therapy/hb175_01/prd/ - got it second hand for under 10 pounds and for smaller sizes it works perfectly. For larger sizes the best way may be building your own source from black light tubes - there are many how-to`s on the internet.

[Francois]

If you choose to go the fluorescent route, make sure the tubes are either labeled BL or UV for the best results. BLB tubes are said to be less efficient.

Or, if you want to go really neat, you could make a carbon arc light
http://www.youtube.com/watch?feature=player_embedded&v=wY06G2iSR8M#!

[Pete_R]

the sodium lights are daylight replicas, but the metal halide lamps (according to Sandy King) work well, he uses a large industrial metal halide type light, but they are quite expensive

I'd have to check but if I remember correctly, not all metal halide lamps are the same. They can have their spectral energy curve tailored to the purpose they are intended for. I'll see if I can find a source for that.

[DonkeyDave]

600w lamp ---   http://www.sunmastergrowlamps.com/SunmasterBlueIce5500K6000K.htm

looks to have lots of UV (as well as visible range light)

Sandy Kings' advice  -  http://unblinkingeye.com/Articles/Light/light.html

the large Metal Halide luminares are over £250 and you need to buy a bulb as well
the bank of tubes including woodwork etc is around £200
the hash kit is £80, includidng ballast reflector and bulb, but appears to be untried at the moment compared with the others

it looks like it should work?

[LT]

My (admittedly minimal) knowledge of most alt printing is that they are printing out processes that can be carried out in sunlight? If so, daylight synthesisers like grow lamps should be fine .... Just maybe not as quick as pure UV?

Then again ... Maybe not.

[LT]

What about vivarium lamps as an alternative?

[Pete_R]

600w lamp ---   http://www.sunmastergrowlamps.com/SunmasterBlueIce5500K6000K.htm

looks to have lots of UV (as well as visible range light)

Sandy Kings' advice  -  http://unblinkingeye.com/Articles/Light/light.html

the large Metal Halide luminares are over £250 and you need to buy a bulb as well
the bank of tubes including woodwork etc is around £200
the hash kit is £80, includidng ballast reflector and bulb, but appears to be untried at the moment compared with the others

it looks like it should work?

Reading Sandy King's article, it seems to me there are plenty of reasons not to use a HID/metal hallide lamps. Not sure why he does use it other than maybe improved sharpness but that seems to be more an effect of the luminaire and the focussing of the light rather than the lamp itself.

I would still suggest, at least as a starting point, using a tanning lamp. It's basically plug and play and cheap.

[DonkeyDave]

I want to eventually get to 16x20 for my exhibition, so the face tanner is too small, however I'm going to be starting out with 8x10s to learn the process.

Looking at face tanners on ebay, you can get the large commercial sun beds for not much - cheaper than making your own

[Francois]

Tanning beds would work just fine.
And if you're in a bind, maybe convincing a local tanning salon owner to let you have a good price on print exposures might be worthwhile.

[ChristineHickey]

Check out used screen printing machines. They can be had for cheap if you look. I bought an Amergraph uv unit with vacuum frame for $250US. It is enormous and can print 26x28. Amergraph and NuArc are good names if you can find them.