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So I just made two captures of a ColorChecker, on a tripod under a GTI light box.
Used my Minolta Flash Meter III for an ambient exosure reading of 15th of a second at F5.6 at ISO 100.
Camera set for manual. Those exposure settings (15th of a second at F5.6).
First capture was set for PPOFF.
2nd capture was set for PP7. Note, I have no idea, never having used this, why the camera controls would NOT let me set this to anything but ISO 800. So my testing may be a tad flawed here and if anyone can let me know what's up, great.
As many should know, ISO has no bearing on actual expsoure. So both captures are exposed identically.
In RawDigger, from what I see numerically, they are nearly idential. Screen captures below (Min/Max/Ave values show tiny differences, I will shoot two identical captures with the same PPOFF but suspect, these tiny numbers are to be expected).
Happy to provide the raws if someone else can provide more through feedback but at this point, it appears: PP settings do not affect the actual raw. What is seen from them in a converter is a different story.
I know Iliah, author of RD, I may ping him as well about this. He's forgotten more about how raw works than I've ever know about them.
Going back to exposure, you can see, even with a good incident meter, RD shows this is under exposed, which is why testing your sesnor and meter and using RD is so useful.
Also, if you view the embedded JPEGs (in my case, from the Mac Finder), the PP7 looks a few stops over exposed, the PPOFF looks fine and yet, the data from the raw is what it is, seen above. So the JPEG from the raw the camera creates isn't at all useful.
Further, when both open in ACR, it renders by default this way:
@Todd Shaner wrote:
You said, Used my Minolta Flash Meter III for an ambient exosure reading of 15th of a second at F5.6 at ISO 100. If you reduced the light level for the 15th second at F5.6 ISO 800 by -2.0 EV as read on your Minolta Flash Meter III then I agree the two files should be near identical.
No sir. The exposure for both was identical. No sir, there is zero reason to alter the ISO on the meter either.
The ISO plays zero role here. ISO isn't an attrubute of actual exposure. Exposure is two and only two attributes which control the amount of light striking the sensor: Aperture and Shutter. The ISO makes zero difference here. The two captures have identical exposures as both, repeat both, were 15th of a second at F5.6.
The ISO being set to 100 vs. 800 doesn't alter this whatsoever.
Setting ISO speed does not change the sensitivity of the sensor to light, like volume control does not change the sensitivity of a radio. In both cases the setting (ISO or volume) controls only the signal processing, while the input stage (sensor, antenna) provides the same input signal.
But when ISO setting is cranked up, automatic exposure results in more noise - automatic exposure in this case decreases the exposure (that is, the combination of aperture and shutter speed is set to allow less light captured by the sensor). Less exposure, less light, more noise. I did not use automatic exposure as I pointed out.
And further, a higher ISO can produce LESS noise than a lower one, again because it has nothing to do with exposure (when the photographer doesn't allow automatic exposure):
@Todd Shaner wrote:A better test would be to set your camera for auto exposure (Aperture or shutter priority), set ISO to 800, shoot a picture, and then without changing the lighting set PP7 and shoot the same picture.
No, it would be another invalid test like the URL provided. PP7 and PPOFF are identical. When everything else is the same (and again, ISO isn't at all a factor here). Had I done as you suggested, the two would differ due to exposure (actual and real exposure) and the test, seeing what PP settings do, alone. Doing as you suggest isn't what the test was about which is to invalidate the URL suggesting, incorrectly, that changing PP settinsg affects the raw. It doesn't.
I didn't use "Auto Exposure" for exactly the reasons expressed.
I noticed in PP7 and auto ISO pulls down the exposure to create the dark picture (and yes the histogram is showing this prior to the shutter closing). Styles as others have pointed out is not the culprit. Solution is turning off PP since i shoot very little video.
Again no! PP7 settings alone, and that IS the test, do nothing at all differently to the raw data. PP7 doesn't affect exposure and RD shows this clearly. PP7 changes the JPEG processed from that IDENTICAL raw from that of PPOFF. Hence the JPEG is again, useless!
And I thought we both knew; the Histogram is a lie and tells us again, nothing about the raw data or its expsoure. But RawDigger does.
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