Several lights through Diffusion Frame

[Felix Wiedemann]

Sorry for asking a question that I could easily find out by testing, but perhaps someone already has experience with this and I don't have much time to work this out.

 

So far I have mostly used a sinlge light only to go through diffusion frames. In this particular case I will need more stop than I get out of say a 10K through an 8x8 diffusion frame. A bigger lamp is not an option in this case, but I have access to more 10Ks. So my question is: Will two 10Ks (both filling the 8x8 frame) give me substantially more stop that one 10K, perhaps even comparable to a 20K ? What about 3 or 4 10Ks:-)

 

Thanks a lot !

[David Mullen ASC]

Sorry for asking a question that I could easily find out by testing, but perhaps someone already has experience with this and I don't have much time to work this out.

 

So far I have mostly used a sinlge light only to go through diffusion frames. In this particular case I will need more stop than I get out of say a 10K through an 8x8 diffusion frame. A bigger lamp is not an option in this case, but I have access to more 10Ks. So my question is: Will two 10Ks (both filling the 8x8 frame) give me substantially more stop that one 10K, perhaps even comparable to a 20K ? What about 3 or 4 10Ks:-)

 

Thanks a lot !

 

Sure it will give you more light - it's done all the time (especially with a long diffusion frame, like a 4'x8'), adding more lights behind a large diffusion frame. The only thing is that it helps to use a thick enough diffusion so that the two lights blend into one that fills the frame, not two slightly softened sources side by side creating two shadows.

[boy yniguez]

Sorry for asking a question that I could easily find out by testing, but perhaps someone already has experience with this and I don't have much time to work this out.

 

So far I have mostly used a sinlge light only to go through diffusion frames. In this particular case I will need more stop than I get out of say a 10K through an 8x8 diffusion frame. A bigger lamp is not an option in this case, but I have access to more 10Ks. So my question is: Will two 10Ks (both filling the 8x8 frame) give me substantially more stop that one 10K, perhaps even comparable to a 20K ? What about 3 or 4 10Ks:-)

 

Thanks a lot !

yep, every doubling of the light adds one stop - one to two, two to four, four to eight and so forth.

[Felix Wiedemann]

Thanks a lot for your help !

[Chris Millar]

yep, every doubling of the light adds one stop - one to two, two to four, four to eight and so forth.

 

Mind that this is true with respect to those sources and those sources only - if there is any other lighting (ambient or otherwise) then this equation wont hold true for the light the film eventually receives.

Edited October 7, 2009 by Chris Millar