Background lighting help

I got a black/white combination muslin backdrop set and did some test shots with my 3 year old and can't get the white backdrop to be white. I have two Calumet 200ws strobes and my 580EX II. I was trying to light the subject with my two strobes and use the Canon to light the backdrop unsuccessfully. I was also getting too much of the background light coming back on my subject. Do I need to snoot the background light or will that focus it TOO much? I need help! I also have three ebay YN460 strobes if I need to bring them into service.

How far the subject from the bg?

I would use your 2 strobes to evenly light the bg and then use your flash for the main light on the subject.

You need the backdrop to be lighter than the subject. Therefore in order to light the subject correctly condider the lighting in two separate segments. The subject and then the background. You need to light the background evenly and separately from the subject so no go on the snoot. You could put one of your 200's jacked up shooting into the black backed umbrella aimed at the wall. You have a small subject so you only need to evenly light a small amount of background. Set the background light just powerful enough to get the backdrop to 'blink' with the exposure warning switched on. Too much and the backdrop itself will give you flare. Also make sure the front and rear lens elements are very clean. a small smudge will cause flare also. Then move further from the wall and use your other 200 with a reflector to get the exposure and fill on the subject. Another solution, as Bobbyz says, may be to use the 200's exactly as shown below and then use the speedlights with umbrellas to light your subject. The more i think of it it's probably the way to go.

I was playing around with a setup like this the other day. The lighting was 4 genesis 400's

Thanks guys. I had the subject maybe 4-5 ft out. I cant' recall for sure. I will try using one strobe to light the BG, one as my main light and use my flash on camera for fill.

imahawki wrote in post #9316501
Thanks guys. I had the subject maybe 4-5 ft out. I cant' recall for sure. I will try using one strobe to light the BG, one as my main light and use my flash on camera for fill.

Problem with using one light for bg is that you will need to place it behind the subject to hide it. Then it can only make certain area of the bg white with white going to grey as you move away from the center.

With two lights on the side, you adjust their positions so that light from the two overlaps on the bg in such a way that light falling on the bg is uniform from one edge to the other, atleast in the part which will be shown in your frame.

In the picture posted above by "111t" the two umbrellas on the bg would need to angled so that light from the umbrellas falls more towards the bg. In the position shown, it won't work as half the light is falling off the bg and in the center won't be much light. Maybe it was quick diagram but I thought I shoudl point it out in case someone tries to replicate it.

Just use your flash as a main light, use a reflector as a fill if you need. You can also use main on camera axis like in beauty lighting (all depending on what you trying to shoot).

There are some ways where one light for bg can work. Say if you have a nice softbox hanging from middle center but positioned so that it is throwing nice uniform light on the bg. You can do it with a boom or ceiling mounted box. Some folks use bare strobes hitting reflectors in the ceiling and coming down on the bg. But then they have multiple strobes positioned a certain distance from each other long the background.

111t wrote in post #9316260
I found that it was necessary to aim the background lights perpendicular to the backdrop as shown in the diagram.

bobbyz wrote in post #9318583
In the picture posted above by "111t" the two umbrellas on the bg would need to angled so that light from the umbrellas falls more towards the bg. In the position shown, it won't work as half the light is falling off the bg and in the center won't be much light. Maybe it was quick diagram but I thought I shoudl point it out in case someone tries to replicate it.

Well that's exactly what i expected when i did the setup. But let me tell you, it works the way i showed it... it didn't work with the lights aimed towards the center. There was way too much spill onto the subject position. If you adjust the lights so that the backdrop is clipped in the middle, it doesn't matter if the backdrop at the edge is more clipped.

That's why i think the op may be able to get by with 1 light to the side and then use the other with the on camera flash as fill. A three year old is only going to take up so much space. I say try it both ways first with 1 light on the backdrop and 1 on the subject w/spedlight fill. If that doesn't work put both 200's on the backdrop and use speedlights to light the subject. You may want to experiment with the lighting prior to getting the subject in the studio.

Whatever you do, Bobbyz and I are expecting follow up photos and a full report.

We used to do this sort of setup with wide reflectors on Norman lh52 heads with homecobbled barn doors... This was a little sort of tinkering that we did over the Chrismas holiday to see if we could still do the lighting with the new Genesis 400's. The setup above is exactly what we came up with.

Try it.

One more thing, I jacked the contrast on my pic from above to point out something. When the photo was taken, the entire backdrop was blinking, however some detail was recorded where the two circular light patterns didn't overlap. Since the backdrop is a shamefully wrinkled muslin... it can be easily seen.