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View Full Version : Gel vs Umbrella



TC
05-18-2004, 12:02 PM
I have some umbrellas, where the black backing comes off, so it's something like a light box. Which would work best for making the light less harsh, The psuedo light box or a diffusioon gel?

filmmaker58
05-18-2004, 08:32 PM
Just go by this rule: The larger and closer the source, the softer the light. When you bounce into an umbrella, it becomes the source, which is larger than the opening of the lamp, so it's going to be softer than even a lamp with diffusion on it. Shoot that light directly into a 4x4 frame of gel, and it becomes the source, so it will be softer.

Experiment by comparing the light when projected through a gel from 10 feet away from a subject, and that same light bounced into a white card 3 feet from the subject.

Aejaz
05-20-2004, 02:26 AM
hmmm

TC
05-21-2004, 08:42 AM
hmmm?

filmmaker58
05-21-2004, 10:59 AM
Was that too complicated? Sorry, maybe I'm not explaining well enough. It's hard to answer the question directly because the light will probably be about the same quality (I'm guessing the umbrella will be a bit softer). So many things things are dependent on light properties. The size of the source, and the distance from your subject. You can have a huge softbox, but if it's 20 feet away from your subject, the light will have similar softness to a light 3 feet away with a sheet of 250 gel on it. Scattered (soft) light drops off quickly, leaving only the harsh beams traveling over distance. Robert Rodrigues got great results from a photoflood with diffusion gel on it in El Mariachi because the light was close to his subjects. The bottom line is that you need to experiment. Set up your camera, and look at the light on a subject using different techniques. But it's a pretty simple formula, the larger and closer the source, the softer the light.

CamOp
05-21-2004, 04:23 PM
Size of source equals sotness of light is right on.

For some reason I am feeling the need to be picky and honor tradition.
Gels don't soften, diffussion does. Gels effect color or intensity.

filmmaker58
05-21-2004, 05:10 PM
I guess in my slang I've always considered diffusion gels to be the ones you clip on the light (opal, 250, 216, etc), and and just diffussion to be silks, grid cloth etc. on frames. But that's just my version of the language.