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Message: <blockquote data-quote="WayneF" data-source="post: 349179" data-attributes="member: 12496">No, the camera distance does not affect exposure.  The flash to subject distance does.Camera distance does affect depth of field... is that what you meant?For example of exposure, the exposure of a mountain is about the same, regardless if you are standing on it, or are a great vast distance from it.  Sunny 16 either place.This is because the Sun is the source, and the distance of the light remains 93 million miles no matter where on Earth that you stand.But flash is extremely nearby, and its distance greatly affects exposure (inverse square law).It is more than enough to know camera distance does not affect exposure (unless the flash is on it), but for more reason, see <a href="http://www.scantips.com/lights/flashbasics1b.html" target="_blank">Camera distance does not affect exposure</a>News photographers in the old days always had the rule "f/8 and be there".  f/8 is generally a sharp aperture with decent depth of field, and being there was the first rule of getting the story.Preferences vary, but a very common rule of thumb for commercial portrait studio portraits is f/8 or f/11.  Nobody wants any unsharpness.  Well, some do, some seem to crave using f/1.8 to blur backgrounds in outdoor portraits.  My own notion that that is often more poor than it needs to be, and instead, using a longer lens (also less depth of field) will first of all, will simply directly crop out most of the objectionable background (that we wish to hide), and then will allow shifting camera position to choose the better narrow part of the background to include (like one bush).  Then two, standing a bit closer to the subject (relatively, not distance, but just meaning tighter cropping) makes the background relatively farther, and the longer lens blurs better than f/1.8 usually does.f/8 should not be much problem for direct flash, or bigger studio flash.  If outdoors in the sun, maximum shutter sync speed probably requires around f/11 anyway.But indoors, hot shoe flash is generally best done as bounce flash, and for bounce flash, ballpark of ISO 400 and f/5 is commonly required (to have enough power to go to the ceiling and back).It is off-subject here, but maybe I can show that depth of field example better.D300 (DX)  50 mm lens, f/1.8 1/6400  ISO 400, 10 feet.   About the worst view of tree scene I could find.   f/1.8 did nothing for it.  Maybe is worse.  Needs to be much closer.<img src="http://www.scantips.com/g2/dsf_4269.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" />D300, 150mm f/2.8 1/800 second.  Camera position shifted left about three feet for better background view (selective).  Tree trunk is about 11 inches, a bit larger than a face. Camera could be rotated vertical.<img src="http://www.scantips.com/g2/dsf_4270.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" />A longer lens is a prime tool for cleaning backgrounds.  Stepping back would increase depth of field (a bit). Way back (3x to 30  feet) would equalize the 150 mm with 50mm field of view, and depth of field at same apertures.  Exposure increase is because narrow view shows more shade and less full sun.</blockquote>

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