Zoom reflector and umbrella

When shooting with a zoom reflector into an umbrella, what setting do you

normally have the zoom reflector on--wide angle or telephoto? How does this

affect the quantity and quality of light falling on the subject, which is 5

feet away?

I think you'd want to adjust the flash-to-umbrella distance and/or the flashhead zoom

setting so that the flash blast just "fills" the circumference of the umbrella without light

spilling "beyond" the umbrella's edges, nor without having a small hotspot in the middle of

the umbrella.

 

You can then change the distance from umbrella/flash rig to the subject to alter the effect

of the light on the subject. Generally speaking, the smaller the apparent size of hte light in

relation to the subject, the "harder" or more "specular" it will appear. A smaller umbrella or

softbox, positioned farther away from the subject, makes harder light. Larger and/or

closer makes softer light.

profoto has a small reflector for umbrellas practically not a reflector...the zoom seems like it

should be as wide as poss....which is the purpose of the umbrella to start with...but then

again maybe there would be an effect that the zoom would bring...more then likely a minor

one ..

I did a little experimenting with my umbrellas & flash units. I found I needed to set the flash's zoom to the widest position and move the umbrella as far from the flash as the umbrella stem/post would allow. The flash still does not fill the umbrella to the edges, but it is as good as I can get it. Filling the umbrella circle will soften the light and shadow edges, which is usually what I'm trying to achieve. Less zoom will reduce the softening effect. I found no difference in the quantity of reflected light either way.

My guess is you will need to use a WIDE setting, and maybe even a diffuser to make it even wider. This all depends on the diameter of the umbrella and how far from the umbrella you position the flash.

 

Go to the bottom of this thread to see how I figured out how to illuminate the umbrella.

http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00HOuH

 

This method is limited to a white or shoot thru umbrella, where you can see the light from the other side of the umbrella. I have no idea if there is any bleed thru with a silver umbrella.

 

The idea is to illuminate as much of the umbrella as possible to get as BIG a light source as possible to get as soft a light as possible. If you over illuminate and get spill over, you loose light and maybe get reflections from the back of the room.