Headshots against cyc fabric

I was asked to shoot some headshots in an auditorium, on the stage they have a drop down white cyc fabric. I am trying for as close as possible white background for the shots. How does the cyc fabric absorb light? Would you back light it or would it be better to bring a roll of white paper?

Thanks in advance

Ok, I'll ask. What is 'cyc' fabric?

If you want white then I would take a roll of white.

Do a few test shots against theirs when you get there and if you like the results, use theirs. If not, use your white.

saea501 wrote in post #17927828
If you want white then I would take a roll of white.

Do a few test shots against theirs when you get there and if you like the results, use theirs. If not, use your white.

Good advice.
Test with their fabric, if it works then just leave the paper in the car.

I don't know why you wouldn't be able to blow it out to white. Being able to light it from behind is just a bonus.

Bassat wrote in post #17927781
Ok, I'll ask. What is 'cyc' fabric?

I'll repeat the question - what is "cyc fabric"?

https://www.rosebrand.​com …644/128-Poly-Cyc-IFR.aspx

"A synthetic substitute for muslin without the wrinkles, Poly Cyc drapes and lights beautifully." it says.

Interesting.

Methinks, as long as you blow out the background to pure white, why does it matter how it absorbs light? (Unless you're trying to figure out how much flash power you need?)

I'd probably be more concerned about how it reflects light, as this will determine how far away my subjects need to be from it, and/or whether to take a couple of large black foamcore sheets to use as flags (one to each side of the subject, just outside the frame).

EDIT: read the original post again. Well, in any case, I'd rather light the background from the front than from the back.

Sorry for the delay, thanks for the help. I tested the cyc with one light and it came out a bit grey so the roll may be an option. I was hoping not to have to purchase a new roll and do this with minimal lights. I do have the option of lighting from behind.

Thanks again

White is white. If something is white, it doesn't absorb visible light. If it did, it would not look white. Bringing in white paper in place of the fabric backdrop should not make any difference.

If it's coming out grey in the photos, you just don't have the ratio of subject to backdrop lighting correct. You should be lighting the backdrop 1 to 2 stops brighter than the subject. How much the backdrop lights spill side lighting onto your subject depends on: the ratio, the distance between the subject and backdrop, and what additional structures you have in place to flag off the backdrop lights (such as v-flats, or the use of gridded softboxes to light the backdrop). For a headshot, you probably don't want the backdrop lights hitting your subject at all, so flag them off or put distance between the subject and backdrop. When the backdrop lights sidelight your subject, you get more of a high-key look, like a cosmetics ad beauty shot, not a clear separation from the backdrop as in your profile pic.

One white background setup:

IMAGE LINK: http://www.ipernity.co​m/doc/diamantstudios/3​6576666

IMAGE LINK: http://www.ipernity.co​m/doc/diamantstudios/3​6576672

You haven't said what you're using for lights, but because this is just a headshot, you can get away with fewer lights than if it were a full body shot. You could put some manner of directional light--ideally diffuse and wide--on the ground just behind where you have the subject stand, aimed at the backdrop (to project a big spot centered at their head level), and not have to worry about flags. Then you just need one light plus reflector for the subject lighting, or two lights if you want stronger fill or a hair/rim light, etc. But you really only need one light to blast the backdrop, provided you have the power for it (doesn't usually take much to blow out an already white wall).

You have to light the white drop separately.

Promo headshots for my dance troupe, using a blown-out white paper backdrop.
We were going to use the large space in the dance studio, but it got booked at the last minute and we got bumped, so we went to the home of one of the performers.

I had the last few feet of my little roll of white paper, and three Speedlights. Not really ideal, but you gotta just make it work sometimes. By standing far away - that is, in the next room - and shooting with a long focal length, I can use a tiny backdrop to still get headshots and even 3/4 shots. This BTS shot is standing in the doorway to the next room, I took a few more steps back for the actual shots, and shot through the doorway.

Setup.

IMAGE LINK: https://flic.kr/p/F7wq​2K

IMAGE LINK: https://flic.kr/p/pRNg​wx

IMAGE LINK: https://flic.kr/p/pTjv​TK