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Old Mar 9, 2003, 10:47 AM   #11
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you know all the histogram stuff is great. and yes it does work as long as the metering system is accurate
Have I missed something here? I thought the Histogram represented the data points which eventually got coded as your JPEG file. This must be true 'cos my 602 displays the histogram of the saved file - after the shot. Therefore it is very independent of metering and sometimes more meaningful than trying to estimate correct exposure from an lcd with the sun behind it! In fact with the histogram you can get some idea what the metering is doing - not the other way round.

Regarding the grey card trick, if you used a white card and checked for minimum (guess) in the 255 bin, wouldn't this give you optimum exposure without white clip and lowest noise to fiddle with the pic in PS?

OK I accept that metering might display histograms you can't understand, and it can shift the scales around, but I thought the data statistic display was just the distribution of brightness data??
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Old Mar 9, 2003, 10:53 AM   #12
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If the camera's meter is off, wouldn't it be off as well reading any grey cards...?

The histogram is much more useful since it not only shows you only the midtone, but its relativity to the entire range of the CCD as well.

On some Nikons the areas of clipping are also highlighted upon review of the histogram 8)
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Old Mar 9, 2003, 10:57 AM   #13
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On some Nikons the areas of clipping are also highlighted upon review of the histogram
This is what I know as 'zebra' which on prof. video cams, introduces an alias pattern onto the viewfinder in clipped parts of the scene, in real time as you compose.
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Old Mar 9, 2003, 10:59 AM   #14
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This must be true 'cos my 602 displays the histogram of the saved file - after the shot.
On the D7 it's done in real-time and superimpose on the EVF!

Unlike some dSLR the metering (as well as the autofocus) is all done through the CCD, albeit at a faster rate (ie every 1/8 line or something) Look at the previous CCD datasheets that I have posted...

Guess what the preflash serve the same purpose for flash photography!
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Old Mar 9, 2003, 11:01 AM   #15
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Yes, I know and envy. I'm sure it's one of those features that a software mod. could change - but that's not possible on the 602.
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Old Mar 9, 2003, 11:45 AM   #16
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From sjms post: http://www.luminous-landscape.com/tu...stograms.shtml

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Start using the histogram review feature of your digital camera. Set your camera to display a combined thumbnail and histogram for 5-10 seconds after every frame. Get in the habit of glancing at it. It's the greatest invention since the built-in light meter.
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