RAW: How to use histogram to judge exposure

[boku]

When I'm shooting in RAW mode with my D70, I've observed that the post-exposure histogram displayed depends on the contrast, saturation, and sharpening settings I've programmed (in the "Optimize Image" menu), even though these settings have no effect on the RAW file itself. Presumably, this is because the camera is actually displaying the histogram of a JPEG image derived from the captured RAW file using the programmed image settings.

This leaves me confused about how to use the in-camera histogram to judge exposure, and how to set the parameters that affect the histogram (but not the RAW file itself). I've been setting the contrast, saturation and sharpening to their lowest possible values, but I'm not sure if this is the right thing to do in every situation.

Any insights into this issue from the experts on this group would be greatly appreciated.



Venkat

Your analysis is correct and setting the parameters to the lowest un-enhanced setting is your best bet. Just don't select settings that have less than normal saturation or contrast. If all you camera does is boost these parameters, the select the lowest to prevent the boost. If your camara can boost or reduce, then select the setting that does neither.

But NO sharpening is where you want to be.

[venkat0210]

Bob & Jonathan,

Thank you for your responses. I'm going to do a few more experiments based on your suggestions, and will report back if I still have problems.


Venkat

[Jonathan Wienke]

Minimum number. The native color space of the camera is greater than either sRGB or Adobe RGB, so that will get you closest to matching the RAW data. At least that is the case with my personal 1D-MkII. YMMV somewhat, and I'd recommend doing the testing I outlined in my article to verify, but that's what works for me.

[venkat0210]

When I'm shooting in RAW mode with my D70, I've observed that the post-exposure histogram displayed depends on the contrast, saturation, and sharpening settings I've programmed (in the "Optimize Image" menu), even though these settings have no effect on the RAW file itself. Presumably, this is because the camera is actually displaying the histogram of a JPEG image derived from the captured RAW file using the programmed image settings.

This leaves me confused about how to use the in-camera histogram to judge exposure, and how to set the parameters that affect the histogram (but not the RAW file itself). I've been setting the contrast, saturation and sharpening to their lowest possible values, but I'm not sure if this is the right thing to do in every situation.

Any insights into this issue from the experts on this group would be greatly appreciated.



Venkat

[Jonathan Wienke]

Presumably, this is because the camera is actually displaying the histogram of a JPEG image derived from the captured RAW file using the programmed image settings.

That is correct. I'd recomment setting all "enhancement" parameters (sharpening, contrast, saturation, etc) to their minimum values. http://www.visual-vacations.com/Photogr....ies.htm has more details.

[jule]

That is correct. I'd recomment setting all "enhancement" parameters (sharpening, contrast, saturation, etc) to their minimum values.

So Jonathan, just to clarify...on a 1dsmk2 are you meaning for the contrast 'minimum values' as 0  ( minimum alteration)  or -2 , (minimum number) and in light of what Boku suggests, and i think you are inferring, that the 0 is the setting that neither boosts or reduces contrast and therefor the minimum value. Am i correct in assuming this?

Thankyou,
Julie

[jule]

Thanks Jonathan.
Julie