I am looking for suggestions on lighting a 30' wide white background evenly. I have used one silver BD and two umbrellas last year. I could not get the light in the middle to match the out sides where my lights must stay I am looking for a very evenly lit background. I was thinking of trying a Retro laser reflector to shoot light in the middle this year does any one else have any suggestions?
I've got a 35' wide white cyc wall in the studio and the simplest way I've lit a huge section of it is shooting into v-flats made of two 4 x 8 foamcore sheets. If the strobe head is moved into position where it fills the open v-flat uniformly, it will throw very even light. One of these on each side will do very nicely in most situations. I've also used a "tree" of stacked white umbrellas which works very nicely, but is a bit more time-consuming to set up. Metering across the cyc wall, I've been able to get very even readings.
squeakski wrote:
I am looking for suggestions on lighting a 30' wide white background evenly. I have used one silver BD and two umbrellas last year. I could not get the light in the middle to match the out sides...
A beauty dish isn't an ideal tool to use as a background light. A third umbrella would probably have been better.
What was the problem with the lighting? Was the middle too bright, too dim, had a hot spot, etc.?
How were you using the two umbrellas? That is, was the left umbrella aimed to light the right side of the BG, the the right umbrella the left BG; or were you lighting left with left and right with right?
I had some hot spots on the sides to get the middle bright. I was thinking that the umbrella’s would spread the light out more and the BD would keep it a little tighter. Getting light to the middle is my main problem.
I learned from my job operating a copy camera that the inverse-square law needs to be taken into account when trying to light a copy board / flat art or a background with lights from the side.
You need to take into account the footprint of the sources, their distance to their respective sided and the distance / overlap of the two in the middle. If both lights are aimed at the middle the overlap of the two will usually create a hot spot in the middle. it is necessary to feather the lights out closer to their respective sides about 1/3 of the way in from the edge to wind up with more even light between middle and edges. That will vary depending on how far the lights are away from the background and how big their footprint is and how much of that footprint is bouncing off the ceiling adding "spill fill". The closer the lights are to the sides the more rapidly they will fall off across the background. So the further they can be placed the less fall off and the easier it is to create evenness across it. As with a LightSphere sometimes bouncing the light off a similar white ceiling is an effective way to help evenly light the space.
Tone around the feet on the floor in the foreground can be controlled by feathering the key and fill in front to put more or less light there as need to balance the light bounce from the back with the frontal sources.
With a digital camera rather than running around with a meter I find it simpler to just open the lens 1/3 to 2/3 stops wider than I want to shoot at and use the clipping warning to show me whether or not the lighting is even. When I can get the entire background clipping at the same time I know it's even, then I can stop down the lens to put it at, or as I prefer, a bit under clipping at capture.
