  Started Oct 17, 2011 | Discussions thread Great Bustard Forum
ProPosts: 19,214 Entirely 'quite' In reply to boggis the cat,
Oct 22, 2011  boggis the cat wrote:  Great Bustard wrote:
boggis the cat wrote:  The difference between systems in terms
of light collecting ability for lenses using the same f-ratio
and photos displayed with the same area is quite simple:    •
4/3 vs 1.6x: log2 (332/225) = 0.56 stops more light on the 1.6x
sensor.    • 4/3 vs 1.5x: log2 (372/225) = 0.73 stops more light
on the 1.5x sensor.    • 4/3 vs FF: log2 (864/225) = 1.94 stops
more light on the FF sensor.  Not quite, because of the
efficiency of the aspect ratio.  That, and the rest of my post,
was 100% correct.   They ignore nothing. You simply don't
understand what they are saying (a familiar story). Here -- I'll
spell it out to you. For the figures above, the assumption is
that we are taking a pic of the same scene with the same
exposure, so that the area of the scene in the focal plane is
the same for both systems.  Remembe