This is about the third thread on this subject in as many weeks, and as I keep writing on this forum, I.S..O. 100 on a digital cameras inbuilt lightmeter that is designed for that individual cameras sensor, it is not the same as I.S.O. 100 on a hand held lightmeter intended for use with film, this is bourne out by tests carried out in the U.K Professional Photography Magazine a few years ago who did extensive tests on this subject.
The only hand held lightmeter I know that is programable for digital camera sensors is the Sekonic L-758, watch this it should help to explain why you get different readings http://www.youtube.com/watch?v=_7SZ58CugpY
Last edited by benjiboy; 10-28-2012 at 04:30 PM. Click to view previous post history.