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<blockquote data-quote="WayneF" data-source="post: 249394" data-attributes="member: 12496">No, exposure does not matter where the camera is (OK, technically if avoiding macro distances, other factors kick in there).It is one of the hardest subjects to explain, so beginners sources never do.&nbsp;&nbsp; It is enough to know that the camera distance does not affect exposure.&nbsp;Yes, inverse square law always exists, but our use of it is about light sources, traveling from there to us.&nbsp;The camera view is a different situation, seeing an illuminated surface out there, and the area it sees is much reduced when it is close, by exactly the same inverse square law relationship, which exactly cancels out, so that camera distance is not a factor of exposure.&nbsp;&nbsp; Yes, twice closer is 4x&nbsp; brighter, but the camera then sees 1/2 size area (1/4 area), so the surface brightness per unit area says constant.&nbsp; &nbsp; See <a href="http://www.scantips.com/lights/flashbasics1b.html" target="_blank">Camera distance does not affect exposure</a>&nbsp; if you dare.&nbsp; <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite1" alt=":)" title="Smile&nbsp; &nbsp; :)" loading="lazy" data-shortname=":)" />Same reason that f/4 is the same f/4, regardless of the focal length or actual corresponding aperture diameter.So same reason that zooming in tight with a long telephoto lens does not change the brightness of the exposure.Regarding your result, try again paying close attention to the details.&nbsp; Move the subject or the camera, it only matters how far the flash has to travel. But all else must be the same.But for example, the sun gives us Sunny 16 exposures of the mountain, no matter how far the camera is from it.</blockquote>

[QUOTE="WayneF, post: 249394, member: 12496"] No, exposure does not matter where the camera is (OK, technically if avoiding macro distances, other factors kick in there). It is one of the hardest subjects to explain, so beginners sources never do. It is enough to know that the camera distance does not affect exposure. Yes, inverse square law always exists, but our use of it is about light sources, traveling from there to us. The camera view is a different situation, seeing an illuminated surface out there, and the area it sees is much reduced when it is close, by exactly the same inverse square law relationship, which exactly cancels out, so that camera distance is not a factor of exposure. Yes, twice closer is 4x brighter, but the camera then sees 1/2 size area (1/4 area), so the surface brightness per unit area says constant. See [URL="http://www.scantips.com/lights/flashbasics1b.html"]Camera distance does not affect exposure[/URL] if you dare. :) Same reason that f/4 is the same f/4, regardless of the focal length or actual corresponding aperture diameter. So same reason that zooming in tight with a long telephoto lens does not change the brightness of the exposure. Regarding your result, try again paying close attention to the details. Move the subject or the camera, it only matters how far the flash has to travel. But all else must be the same. But for example, the sun gives us Sunny 16 exposures of the mountain, no matter how far the camera is from it. [/QUOTE]

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