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Help with White backdrop


I am using an Alienbees 800 with a white and black muslim. The black muslim works great with my one light set up, but my white shows up very gray. I know that I need an additional light to have a high key white. Am I able to purchase a cheap continuous light for that? Or is there anything else inexpensive I can use to help this problem? Trying not to invest too much more $ until I bring more in. Thanks for any advice.


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June 10, 2008

 

Debby A. Tabb
  Not really Nichole.

However you could do some test shots, using your Alienbee on the backdrop while using an on camera flash on your subject,test that and see if you get closer to what you want.
you could also slave a couple of flash units on stands for this.
when you want something bad enough ,
Try Anything!


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June 10, 2008

 

Diane Dupuis
  I bought two 500 watt continuous shop lights and they do a great job on my high key white backdrop!
All for under $25!
http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200309783_200309783

They're hot though!


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June 10, 2008

 

Maria Fonseca
  Diane, my husband has one of those, and I'm thinking on buying another one. Can you post one picture taken with this lights, please!


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June 11, 2008

 

Diane Dupuis
  Pages 6, 7 and 10 in my gallery... White backgrounds done with those lights...


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June 11, 2008

 

Alan N. Marcus
  Hi Nichole,

To cause the background to reproduce pure white: The background must be strongly lit. In a portrait set-up, we light and expose to achieve realistic skin tones. Once realized, you then concentrate on the background.

It is difficult to get the following concept across:
One can force the background to reproduce light or dark by lighting intensity. We merely increase the light energy playing on the background thus we make it go lighter or darker. To achieve you need a way to independently light the background and adjust intensity.

Background lighting is not easy because generally the background is quite large as compared to the principle subject. To light the background with evenness you might need several light fixtures. However, consider a single lamp behind the principle subject (hidden from the view of the camera) directed up at the background.

Adjustment of background intensity: To achieve a white background, you must light the background quite strongly. If possible use a light meter and adjust background intensity so that it is 3 stops brighter than the illumination applied to the principle subject’s skin.

Intensity changes are easily accomplished by adjusting the lamp-to-background distance. Make a test and scrutinize the results. Measure the background-to-lamp distance. If the results are too dark, move the background lamp closer to the background. Carry out the movement changes in a controlled manner. Best method; multiply current distance by 0.7. (zero decimal seven). The result will be a closer distance that achieves a 100% brighter intensity. Example lamp was 5 feet from background so5 feet x .7 = 3 ½ feet. This is subsequently you next test distance Still too dark? Next test distance is 3.5 feet x .7 = 2.5 feet. Etc.

Hope this helps!

Alan Marcus (marginal technical gobbledygook)
ammarcus@earthlink.net


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June 12, 2008

 
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