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dual-flash camera

Camera with two flashes, to minimize shadows
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One problem which is often apparent when taking a flash picture in a dark room is that, if the camera's flash is mounted to the left of the lens, the area behind and just to the right of the subject will not be illuminated by the flash and will thus often be less than 10% as well-lit as the rest of the background. This often results in a very ugly dark shadow just to the right of the subject.

If a camera were equipped with two flashes, one on either side of the lens, then there would be shadows on both sides of the subject but they would be nowhere near as harsh since all parts of the background would be lit by at least one flash, and the difference between full illumination and 50% illumination is noticeable, but it's less than a third as great as the difference between full illumination and 10% illumination.

supercat, Dec 27 2000

Ring flash http://www03.bhphot...A___SID=E3E822DBB20
What about a ring-shaped flash which fits around the lens? Then you get no shadows at all. [hippo]

Martin Parr http://www.widemedi...04/news0000667.html [hippo, Dec 27 2000, last modified Oct 21 2004]

Martin Parr http://www.widemedi...04/news0000667.html
[hippo, Dec 27 2000, last modified Oct 05 2004]

[link]






       Professional photographers do this all the time, of course; even the cheesiest of passport-photo booths has some kind of backfill flash system to avoid the problems you describe. Even the hobbyist can easily enough get detachable multiple flash units that can be wired to the shoe of any reasonable SLR.   

       Are you suggesting something even cheaper, for low-end integrated cameras?
egnor, Dec 27 2000
  

       //Are you suggesting something even cheaper, for low-end integrated cameras?//   

       That's precisely the idea. An extra flash should add less than $5 to the cost of the camera, yet reduce considerably the shadowing problem. Detachable slave flash units would of course work better, but would be both more expensive and more cumbersome in the field.   

       Additionally, having two or more flashes which were located some distance away from the lens would be better than having a ring flash when photographing people or animals, since a ring flash will cause their eyes to glow demonically.
supercat, Dec 27 2000
  

       PeterSealy: I agree that the end-user price increase would be considerably more than $5, but if you look at the camera market the market for all-in-one cameras extends into the hundreds of dollars; for digitals, it extends into the thousands.   

       The dual-flash option is something I see for film cameras at or above the $150 price point (or digitals above $300 or so).
supercat, Dec 28 2000
  

       PeterSealy: I know ring flashes are meant for close-up work, but they don't have to be. The excellent photographer Martin Parr uses a ring flash for everything. See link.
hippo, Jan 02 2001
  

       Yup. Pricey. On the other hand they may just be expensive because the market for them is so small. Many pieces of photo equipment are like this - because a camera manufacturer only sells a handful of 300mm/2.8 lenses a year, they have to charge $5000 dollars for them. In the same way, if every disposable camera had a ring flash, they might be cheap.
hippo, Jan 05 2001
  

       hippo - you're trying to say that if demand increased, the price would drop? I suppose it's possible given economies of scale and the added incentive for new market entrants, but it's a bit counterintuitive.
bookworm, Apr 26 2001
  

       I think the idea of the second flash has merit if it's used as an indirect fill- that is, aimed away from the subject toward a reflecting surface, such as a white wall. Since one can't always count on having a white wall nearby, perhaps a translucent cover over the flash would serve the same purpose- I seem to recall this technique used quite a bit in the 1950s and 1960s.
whlanteigne, Sep 28 2002
  

       "secondary' flash units (triggered automatically by the light from the first flash) are standard units. The electronics in these that does the detecting costs about $2 US; the flash part doesn't cost much more (seeing as they are in disposable cameras anyway).
pfperry, Sep 28 2002
  

       I would think an adaptor for a camera with a hot shoe wouldn't be a problem- kind of a "T" shaped adaptor that slides onto the camera shoe, a pair of flashes slips into the shoes on the top part of the "T." Make that part maybe 12-18 inches across?
whlanteigne, Apr 20 2003
  
      
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