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Old Dec 29, 2004, 10:10 AM   #11
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:-)No, the flash gets it lens/distance setting information sent to it from the camera. It has no sensorto try to focus itself.

The 500dg flash has a infrared focus-assistlampon it, that the camera can use to focuswith in low light.
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Old Dec 30, 2004, 10:27 AM   #12
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pclements wrote:
I am just interested in the how and why a flash needs to focus.

I think you may be using "focus" differently. A flash like the 500DG Super will focus its beam of light to be (close to) the same field of view that the lens has -- that way, the light is focused on the area viewed through the lens. There's no wasted light, "spill-off," and all the power of the flash canbe used where the picture is being taken.So, when theflash"learns" from the camera that theit's taking a picture at55mm, the lens will "focus" (orto use a better word "zoom") down to that field of view.

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Old Dec 31, 2004, 8:01 AM   #13
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Thank you PeterP & Perdendosi, that makes more sense to me. I just was not thinking of focusing the light so as to not loose spilled light.
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