Hi. I am new to wet plate photography. I am hoping to get some advice about how to make studio portraits using artificial light.
I’ve understood that collodion is sensitive to blue/green wavelengths but not so much to yellow/red wavelengths, and some say that strobes and LED lights are not effective for wet plate photography.
Here are my questions:
1)I have Profoto Acute2 2400. Would this be too weak?
2)Another light I have is Yongnuo YN-900 LED Video Light(900 LEDs, 5500K). If I use a blue filter over the light would that help?
Any tips or technical advice is greatly appreciated!
2400WS is barely going to accomplish the job. If you plan to modify the light source (IE: use a softbox or similar to make the light more flattering) then you will find it even more difficult. And you should plan to modify the light quality if you want to make flattering portraits. I see
so many strobe-lit portraits done on collodion that used unmodified light (or marginally modified) and they are almost always
very unflattering. The more successful strobe/collodion portraitists I've watched use one or two 4800WS heads in a light modifier, plus a fill light. (Or a very good reflector)
And as others have pointed out, blue filters won't help you at all. The remove some wavelengths, but they don't
amplify anything.
If you are limited to a single 2400WS strobe, then you need to work to get the best speed out of your collodion. There are a couple of things you can do to achieve this: use a fast collodion. The UVP-X formula Brian Cuyler makes (at UV Photographics) is about one stop faster than most other formulas. In your scenario, one stop could make the difference between failure and success. Secondly, learn the limits of your materials: test and test some more to determine exactly how far you can push your development times without fogging the blacks. You may want to experiment with how much restrainer (Acid) you can add to the developer to extend development times. Just watch out that you don't create an unflattering tonality in doing so (ugly contrast) The longer you can leave developer on the plate, the brighter the image becomes. There is a very real limit to how far you can take it, of course. Adding one or two grams of Potassium nitrate (Saltpeter) to your developer can brighten the higher values a bit also.
I believe Wilfried Thomas uses strobes for his portraits, and this is how to do it well:
https://wilfriedthomascollodion.files.wordpress.com/2017/12/morgane-ambrotype.jpg Take a look at Giles Clement's portfolio too - he does a very good job with strobes and tintype.
I hate to single out any particular practitioner, but here is an example of what I regard as a very unflattering wet plate portrait, made with unmodified strobe:
https://petapixel.com/assets/uploads/2013/08/Lumiere_Tintype_Collodion_Ambrotype_1423.jpg