What kind of lighting for 4x5 wet plate portrait photography?

[4x5fan]

I haven't been able to find any successful information on studio lighting for wet plate portraits using a 4x5 camera. Can someone suggest the type of possible studio lights I can use and where I can purchase them?

[Mark Woods]

If the wet plate process you're using is blue sensitive, strobes are the best bet.

[ghostcount]

Sign up on Quinn's forum at www.collodion.com then read these (compiled by Garrett).

http://www.collodion.com/forum_posts...-strobes#72996
http://www.collodion.com/search_resu...KW=fluorescent
http://www.collodion.com/forum_posts...ting&PID=34845
http://www.collodion.com/forum_posts...ox-light#74527
http://www.collodion.com/forum_posts...exposure#74510

Fair warning... it's a subject often asked and answers can get pretty technical so the discussion are long and drawn out. Regardless, there's valuable information in these links, you just have to filter what you think is relevant to your needs.

[vdonovan]

The short answer is: a LOT. For our tintype portraits at Photobooth we had two Profoto Acute2 powerpacks, driving two flash heads going into a large softbox and another head acting as fill, along with several reflectors. So over 4000 watt/seconds of light, and it was barely enough.

[4x5fan]

Would it help if I did it outside on a sunny day?

[vdonovan]

Well, you asked about studio lighting. Depending on the solution, wet plate collodion has an ISO of about 3 (or less), so you can figure it out from there.

[Mark Woods]

I have a Speed-O-Tron quad head that will output 9600 watt seconds. I suggest something like that for your needs. I know my still lifes use it all to get a decent stop. My film is EI 50, so I have a ton more sensitivity than your EI 3.

[goamules]

The easiest and best wetplate lighting (brightest for shortest exposure) is outdoors, in open shade, facing north. It's free, easy, and you should get about a 2-10 second exposure in the middle part of the day, depending on lens speed, clouds, etc. Go to Collodion.com like suggested above, and the Wetplate Photography website. Then choose a manual, and you'll learn fast.

Artificial lighting for wetplate can be expensive, and slow. With a bank of compact florescents, you may be at 1 minute exposure. Good for still lifes, not for portrait sitters. Strobes put out a lot more light, but still less than for film....wetplate is mostly working by the blue and UV end. So you get about 1/3 or less of the power you think you are. So you have to blast your sitter with a thermonuclear EMP..... to me, it ain't worth it, I shoot in natural light.

[jcc]

If I remember correctly, we pumped this set up about 6 times—all at maximum power—and it still wasn't enough! More importantly, not all collodion are created equal. Some will be slower than others. Depends on its mixture.
But what was already stated above is true, they are all more sensitive to UV-blue-greenish spectra. Natural light is wonderful during the day, but not quite bright enough at night.

[Joe Smigiel]

I'm tempted to tear a hole in my roof. For indoor work you can't beat a large north skylight because that makes it closer to outdoors (assuming your glass doesn't absorb UV).

In an attempt to mimic that kind of lighting I purchased a 4' square, 16-bulb T5 fluorescent fixture (Quantum "Bad Boy") and filled it with 54w actinic aquarium lamps. I get manageable exposures (3-8 seconds in the f/5.6-f/8 range) with it at portrait distances. Cost was about a grand.

I also have a Speedotron 9600ws quad light that allows for a one-pop exposure in the f/5.6 - 8 range as it drains two 4800 Blackline packs, but I prefer the continuous lighting.

As mentioned before, your best option is probably clear north skylight outside in open shade if that fits your vision.