Is there a rule of thumb for distance from subject to strobe arm spread?
Posted 25 October 2012 - 01:39 PM
Is there a rule of thumb for how far to spread the strobe arms based on how far from your subject you are? e.g. if you're 5' from your subject you want to have your arms 10" extended on each side or is it merely a function of the angle of coverage of your strobe and playing with arm extension until you get the light coverage you want?
Posted 25 October 2012 - 02:11 PM
The general rule, with strobes pointed straight ahead, is to spread the strobes by the same distance as the subject is from the camera. If the subject is one foot away, the two strobes should be six inches to each side - one foot between them. This arrangement minimizes backscatter. If you cannot spread the strobes far enough, point the strobes sightly outwards to illuminate the subject with the edges of the light cones.
Edited by jlyle, 25 October 2012 - 02:13 PM.
8mm, 12-50mm, 45mm lenses
My web page.
Posted 26 October 2012 - 05:20 AM
Posted 26 October 2012 - 12:04 PM
Posted 29 October 2012 - 02:56 PM
You need to know the angle of coverage of your strobes which is given by the manufacturer
This equation assumes you point the strobes straight forward and that they are in line with the port
the distance between the strobes in your case is 2.85 the subject distance
So if your arms plus clamps are 14" each and the tray is 12" the total is 40" and you can get 14" close to a subject. To go further away you need longer arms as the strobes need to be behind the port
Edited by Interceptor121, 29 October 2012 - 03:37 PM.