Quote: Which handheld meter does that, and in what conditions? An incident-light meter might, but a reflected-light meter would typically behave otherwise - and that's what DSLR's have,
I am referring to an incident light-meter which is what I use commonly.
Quote: Basically, you are describing the exposure you prefer - and that's common. But this is not *correct* exposure. Correct exposure of a solid bue sky should have the histogram somewhat left of center. A few white clouds shouldn't necessary change that either way. If the sky is mostly white clouds, then *they* should end up slightly left of center, and the blue that much further left.
I just can't see how the composition of a scene (wether or not it has clouds, brick walls, trees or red cars in it) can influence the "right" exposure...
Furthermore, the correct exposure for white clouds is the one that renders them... white. If I follow you, you're saying that white clouds should end up slightly left of center (ie slightly under middle grey) which should render them as darkish grey. How can this be considered "correct"?
Or did you mean that if I am using a "dumb" reflective meter such as spot metering, it is the result I should get?
In the later case, I agree but we are talking about evaluative metering and the whole purpose of it is that it is supposed NOT to act like a dumb reflective meter.
One ISO value + one aperture value = one shutter speed value for the correct (in the sensitometric sense) exposure.
Then I might want the scene to appear clearer or darker but that has nothing to do with the meter giving me the "correct" exposure for starter.
Quote: These are "correct" exposures, but they aren't t necessarily the exposures you might *want*. And that's why exposure compensation was invented - to allow you to get the exposure you *want* even though "correct" exposure differs.
OK, I think I get that...
Quote: Your book, however, is not what camera manufacturers are compelled to follow. ISO has produced standards for camera exposure, and they specify things work as I've described. *That* is the book followed by camera manufacturers.
Quote: And really, when you think about it, it's *impossible* for a reflected-light meter like that in the camera to render white as white and black as black in all or even sot cases. A plain sheet of white paper versus a plain sheet of black paper - a camera has *no idea whatsoever* that these are in fact different sheets of paper. As far as the meter is concerned, both are just as likely to be a sheet of gray paper in good light (the one that appears white to our eyes) versus a sheet of gray paper in poor light (the one that appears black to our eyes). All of these would reflect exactly the same amount of light to the meter, and that's why they all get metered the same way by any reflected-light meter. Only an incident-light meter would be able to tell the difference and meter the sheets of paper as you suggested.
Matrix metering is supposed to work differently than that although it would probably fail the white sheet of paper test.
Nevertheless, a good matrix meter should be able to do a resonably good job in most cases documented in the camera internal database. How do I know? Well, I have several cameras that seem to work it out... the K10 not being one of them
Quote: This is essential to understand if you wish to be able to work with your camera's reflected-light meter. and not constantly wonder why it doesn't do what you expect. It does pretty much *exactly* what you expect if your expectations are set by science and ISO standards rather than your subjective impressions of what you might "want".
If you were right, all cameras would expose the same in matrix/evaluative metering since they would all be based upon the same "science and ISO standards". But the fact of the matter is: they don't and some do a better job than others, probably just because of better programming and more extensive databases of "photographic situations".