Finding Wrinkle Free Chroma-key Fabric Backdrops?

Greetings Professionals!

I will be doing outdoor fashion photography and a fabric backdrop is my preference over paper. I will need to test clean white and chroma-key backdrops. I'm considering either Muslin fabric or a stretch Lycra fabric. I've never attempted this before and I would appreciate some professional insight and suggestion in order to avoid hick-ups during production.

Thanks in advance for your timely remarks!

Ok! Thanks Sandy!

I'm thinking of shooting a keyed background outside to save money really. I intend to test this out during a personal project before I consider doing it for a paid assignment. I will create a canopy to assure even shade and use a single strobe light as my key. WAngell, do you foresee a discrepancy with shooting a keyed background outside? I foresee that I may experience issues with a few aggravating bugs; that's about it though.

Macintosh, if you need to be wrinkle-free, the stretchy material over a frame is probably best. Outdoors, I'd worry most about wind turning it into a sail. Depending on what you're doing, you might not need completely wrinkle-free; if you light mostly from the front, plus had it slightly out-of-focus, then tiny wrinkles won't have any effect. In this case, depending on how large your scene is, you might even get by with one of those "pop open" backgrounds (they are loaded with tiny wrinkles).

Another option, if you're building a substantial structure, with a back wall under your canopy, is to paint the back wall. Stage supply stores used to typically stock the official (expensive) paint of a major name brand, but I think there have been alternate paint formulas posted on the internet that work about as well for something like 1/3 the cost.

When you say, "use a single strobe light as my key...," do you mean this would be the ONLY light? This would be a problem for the chroma key - when you let part of the background go full black, there's no color info there, and the software can't automatically find these areas. So you should get at least some light over the whole background.

If you've never used chroma key before, be forewarned that there are a lot of difficulties - the background has to be appropriately sized and lit to appear real. (Fantasy backgrounds have a lot of appeal as everyone knows they're not real, so they're not so finicky about the details.)

I've done some serious experimentation with (mainly) green screen 6 or 8 years ago, and came to the conclusion that none of the systems can be fully realistic - you have to settle on some level of what is "good enough" quality. As an example, people tend to lose "mass" from their hair - the outer parts of the hair, with loose strands, tend to take on the color of the chroma key, so are not dropped out; blonde hair behaves much differently than dark hair.

Anyway, high quality chroma key is not as simple as many would have you believe. Best wishes on your project.

Ps, official green screen software usually has an adjustable feature to deal with so-called "smear," where a slight greenish cast enters the outer parts of the subject. If you don't use such software, be prepared to deal with it by hand.