Paul C. Buff, Inc. Technical Forum

For those with real-world experience, is the B800 too powerful to use in a beauty dish up close without a sock for headshots? I usually shoot around f/2/2 or f/2.8 at the narrowest aperture.

According to the expected output guide, the B800 would be just slightly above that output at minimum power with the sock removed.

I guess I could use an ND filter over the lens, but I would prefer not to.

Thanks in advance.

You would be right there at minimum power and a white beauty dish.

You could back the light off a couple of inches, use an ND filter on the lens, or use an ND gel over the beauty dish. 20x24 gels are typically less than $8, and you can cut 2" off the wide side, tape it to the narrow side, and end up with 22x22" gel, and no optical loss. Alternatively, if your camera has ISO 50, or Lo1, 2, or 3, these settings will also work.

Lastly, an Einstein has all of the power range of a B400 and 1600 (and encompassing that of the 800's), plus it goes one stop lower than the B400.

Thanks for the suggestion about gelling the beauty dish.

David Hobby has another suggestion for gelling a beauty dish here:

http://strobist.blogspot.com/2013/11/ho ... h-v20.html

Which looks like it might be easier (he uses blue, but obviously an ND gel could be used instead). My concern would be whether the shield would be too hot though from the modeling light.

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Also, I see the expected power output chart lists the beauty dish and different reflectors, but it doesn't list the expected output of PLM's or non-plm umbrellas. If you have any measurements for those, it would be greatly appreciated.

That is a good method for fixed deflectors, however, our BD has a deflector that is on an independent shaft. My suggestion also came from Mr Hobby in an earlier post: http://strobist.blogspot.com/2013/01/ho ... urces.html

Also, doing this the way I mentioned reduces heat build up and keeps the material from touching hot surfaces.

PLM measurements can be found here: http://www.paulcbuff.com/plm.php then click the "learn more about the XXX PLM" link for each, then click the specifications tab.


Note: these measurements are done at 14' and using the 86" PLMs. Given the size and nature of the PLM, the inverse square law may not be strictly followed at closer distances.