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Message: <blockquote data-quote="WayneF" data-source="post: 352168" data-attributes="member: 12496">I wonder where this notion started lately?  <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite1" alt=":)" title="Smile    :)" loading="lazy" data-shortname=":)" />   Where did you hear this?(my bucket numbers are not precisely 3:2 aspect, but I think I'd need more buckets, and my yard is not that large.  It is close to 3:2, plenty close enough)We have very many identical buckets.Let's imagine we put one array of buckets out in the backyard, say 33x21 buckets, and we call that array FX. And beside it, we put another array, 22x14 buckets, and we call it array DX. The FX dimensions are 1.5x the DX dimensions, DX is 2/3 the size.It rains, and the buckets act like rain gauges, and collect the rain water (much like the sensor cells collecting photons). We do collect half again more total water in the 33x21 buckets, but the water in each bucket is the same.EDIT:  Oops!  Sorry, my hasty error.  1.5x1.5 is 2.25 times more area/water.   Still same in each bucket.Exposure works on the intensity of the light (one bucket, like rain fall), not the total collection over a large area.  The lake may be large, but the rain gauge is not.   Total collection just depends on the collection site size, which is an arbitrary area.<a href="http://en.wikipedia.org/wiki/Exposure_%28photography%29" target="_blank">Wikipedia </a>says "Photometric or luminous exposure Hv is the accumulated physical quantity of visible light energy (weighted by the luminosity function) per area applied to a surface during a given exposure time."."Said again: Exposure is not the total amount of light that falls on a photographic medium, but instead is the amount of light   per area unit (lm*s per m2).  Basically, how bright is the light?Putting more buckets in the yard does not affect how much rain falls (into each).If the FX exposure was f/8, then DX should be f/8 too.  FWIW, a tiny handlheld light meter cell reads it as f/8 too.   There must be dozens of camera sensor/film sizes, tiny cell phones and large film sheets, and every one of them would use f/8 here too - assuming same ISO and shutter speed and same uniform scene  (they possibly could have different field of view, different metering area, a different argument).  But we do Not have to buy a uniquely calibrated light meter for every sensor/film size.  One size fits all.</blockquote>

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