Distance between flash head and umbrella...

[rpcrowe]

Obviously the softness and the intensity of a flash modified by shooting into an umbrella will be different as the umbrella is moved closer or further from your subject.

However, given that the umbrella would be in the same position relative to the subject, how does the distance between the flash head and the umbrella impact the light? Many flash heads allow the umbrella to flash head to be adjusted.

[Jim B.]

If you move the umbrella closer to the flash you will get a tighter light circle (source) and it will produce deeper shadows.

[Colin Southern]

Hi Richard,

As a rule, attach the umbrella pretty close to the end of the shaft ... the further back it is the bigger the light source ... and the bigger the light source the softer the light and the softer the light, the better the shot.

Moving it closer starts to create what we call directional diffused light - not to say it can't be used - but personally I don't use it all that often.

The other variable is the zoom setting on the flash head -- if you go too wide you lose a LOT of power.

[rpcrowe]

Thanks... I suspected that but, it would have been pretty hard to try and to judge the results.

I use old White Lightning WL-5000 monolights. These don't have a variable flash head however, the reflectors are wide enough to full the umbrella from just abut any distance. They don't have a lot of bells and whistles. They are just basic lights that keep going and going. I have had a pair of these old lights for over twenty years and I bought them used for $50 (USD) each. That amounts to $2.50 (USD) per year of use.

[Colin Southern]

Ummm - oops - forgot to mention that I was talking about shoot-through umbellas

As a rule I don't use reflecting umbrellas as light quality is all about how big the light source is, and how close you can get it ... and you can get it a lot closer with shoot-through umbrellas.

[rpcrowe]

I now have a shoot through umbrella with which I am experimenting. Previously, I didn't like shoot through umbrellas because of the backflow of the light. The type which I am now using has a black enclosure covering the open area of the umbrella with a drawstring hole to cinch the black cover around the flash reflector.. This prevents the light from bouncing all over the room, which can cause lighting and color balance problems - especially in rather small shooting environments. It almost seems like I am working with a softbox, but, the umbrella is easier to setup and break down. If the one shoot through I have works out, I might very well switch to all shoot through umbrellas.

http://cgi.ebay.com/2-x-40-White-Bla...efaultDomain_0

Here is another type of umbrella which should give a very soft light - it is the reverse of the model above.

http://cgi.ebay.com/Umbrella-Softbox...efaultDomain_0

BTW: It seems like a flash with a larger reflector does better than one with a smaller reflector when using a shoot-through umbrella. My WL-5000, "coffee can" units provide a softer light than my Multiblitz monolights with smaller sized reflectors and definitely better quality lighting than using a hotshoe flash and shoot through umbrella (Strobist style). My "coffee cans" have a reflector diameter of 7" which gives an approximate reflector area of 121 square inches. Contrast this with a reflector area of approximately 5.25 square inches for a 550EX size flash reflector. It seems like using a softbox or shoot through umbrella to diffuse light made specular by the tiny hotshoe flash reflector is like boiling ice cubes to make tea. It can be done but, it certainly isn't the most efficient way to complete the project.

[Colin Southern]

BTW: It seems like a flash with a larger reflector does better than one with a smaller reflector when using a shoot-through umbrella.

Elinchrom have a specialty reflector just for umbrellas - nicknamed a "spill kill" (life can be so hard at times)

PS: Light being fired backwards from a shoot-through shouldn't cause you much grief as it's intensity has dropped off so much compared to what hit's the subject from only a metre or so away from the shoot-through portion.