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Pair of Omnis for creating bright white background?
http://www.paulcbuff-techforum.com/viewtopic.php?f=8&t=4426		 Page 1 of 1
Author:  jzucker [ Fri Apr 25, 2014 8:31 am ]
Post subject:  Pair of Omnis for creating bright white background?
When shooting fashion white backgrounds, I have been using a pair of einsteins with 7" reflectors, pointed at the background, about 10 feet apart, 2-3 feet from the bg and angled to overlap slightly and to produce about F11(ish) against the white paper. (Camera typically at F8)

With the 7" reflectors, there is a slight hot spot and falloff. I was wondering if the omni would give me a wider spread from the same distance and allow me to eliminate the hotspots?

The one advantage of the 7" reflectors is that I don't have to flag the model from the edges of the light hitting the background. Maybe with the Omnis I'd have to setup some black v cards?

Thoughts?
Author:  Technical Support [ Fri Apr 25, 2014 9:41 am ]
Post subject:  Re: Pair of Omnis for creating bright white background?
7" reflectors will have and 80 degree spread, vs. the Omni with a 30 degree spread. The slight overlap may be what is causing the hotspot.

I would cross light the back ground, i.e. left light aimed at the right, right light aimed at the left. The more distance you can have between the lights and the back ground, the more even and full the coverage will be.
Author:  jzucker [ Fri Apr 25, 2014 3:32 pm ]
Post subject:  Re: Pair of Omnis for creating bright white background?
Technical Support wrote:
7" reflectors will have and 80 degree spread, vs. the Omni with a 30 degree spread. The slight overlap may be what is causing the hotspot.

I would cross light the back ground, i.e. left light aimed at the right, right light aimed at the left. The more distance you can have between the lights and the back ground, the more even and full the coverage will be.


Thanks, i was thinking the omnis with the sock vs the 7" reflector. So I'd be getting 120 degree spread but I'll give a try to the cross lighting. The issue with that is that some light may spill back on the model creating hot spots.
Author:  Luap [ Fri Apr 25, 2014 4:25 pm ]
Post subject:  Re: Pair of Omnis for creating bright white background?
It's not about beam spread - it's all inverse square law. Using Omni's would be worse than 7" reflectors. With diffusers, you would get all kinds of forward spill light. Without diffusers, or with grids the beam would be too narrow.

I have to agree with Tech – cross aiming them and taking some test shots is the best solution I know of.
Author:  Technical Support [ Fri Apr 25, 2014 4:25 pm ]
Post subject:  Re: Pair of Omnis for creating bright white background?
Yes, the socks will have a wider spread, but depending on how close they are, the middle of the back ground will be brighter than the top and bottom, since they will be farther away (assuming the light was placed at half the height of the BG).

This can certainly be done with either reflector, but I generally can light a full 9x10 backdrop with ~14 feet between the background lights, using a 7" reflector and barndoors (or otherwise flag for the subject).
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