[rogerstg]

I was reading my KP manual and came across this regarding setting Highlight and Shadow correction:

"Expands the dynamic range and enables a wider range of tones to be recorded by the CMOS sensor and reduces the occurrence of overexposed/underexposed areas."

It seems that the camera's default setting is Auto. I wonder why shouldn't it be set to "on/maximum"? What's the downside to expanding dynamic range this way? ~thanks

What's the downside to expanding dynamic range this way?

Scenes that don't have a wide dynamic range are rendered flatter than they would be otherwise; they look dull, it might be too much of a good thing.

[Adam]

Scenes that don't have a wide dynamic range are rendered flatter than they would be otherwise; they look dull, it might be too much of a good thing.

Indeed. HDR photos inherently have lower contrast, which may at times look worse.

[stevebrot]

"Expands the dynamic range and enables a wider range of tones to be recorded by the CMOS sensor and reduces the occurrence of overexposed/underexposed areas."

The description is a bit misleading in that the dynamic range is not actually widened; doing that would require multiple exposures (HDR). While the full details are not known with any certainty, highlight/shadow correction appears to be done primarily by applying up to one stop +/- exposure compensation using sensitivity shift with additional tweaks being applied to in-camera JPEG output. Since the behavior is somewhat unpredictable, it is common practice when responding to poor exposure help requests on this site to suggest setting both to "OFF" when doing troubleshooting.


Steve

---

Last edited by stevebrot; 12-16-2018 at 10:26 AM.

[rogerstg]

The description is a bit misleading in that the dynamic range is not actually widened; doing that would require multiple exposures (HDR). While the full details are not known with any certainty, highlight/shadow correction appears to be done primarily by applying up to one stop +/- exposure compensation using sensitivity shift with additional tweaks being applied to in-camera JPEG output. Since the behavior is somewhat unpredictable, it is common practice when responding to poor exposure help requests on this site to suggest setting both to "OFF" when doing troubleshooting.
Steve

Thanks for the info. I suspected that there was more to the story. I have both set to "auto" yet only use RAW output, so I guess that it's irrelevant for me since it only affects JPEG.

[stevebrot]

I have both set to "auto" yet only use RAW output, so I guess that it's irrelevant for me since it only affects JPEG.

To be honest, I don't know if the exposure comp is done with RAW as well. I suppose it would be easy enough to test.


Steve

[aaacb]

To be honest, I don't know if the exposure comp is done with RAW as well. I suppose it would be easy enough to test.

AFAIK shadow correction is only applied to jpeg, but highlight correction affects the raw file. At least on my older k3ii, highlight correction can only be enabled at iso 200 and above, it works by underexposing the image 1 stop and then amplifying with a different curve that doesn't raise highlights as much as the other tones.
I read about this on this thread, haven't tested it myself, normally I shoot raw with both disabled https://www.pentaxforums.com/forums/190-pentax-k-1/363718-settings-affect-ra...ml#post4249424

[stevebrot]

AFAIK shadow correction is only applied to jpeg, but highlight correction affects the raw file. At least on my older k3ii, highlight correction can only be enabled at iso 200 and above, it works by underexposing the image 1 stop and then amplifying with a different curve that doesn't raise highlights as much as the other tones.
I read about this on this thread, haven't tested it myself, normally I shoot raw with both disabled Settings that affect Raw or only JPG - PentaxForums.com

That is my memory as well, but I did not have a reference. I just tried to do a test, but realized quickly that whatever it does leaves almost no trace in the EXIF and that I would need a well-controlled setup to do a reasonable test.


Steve

[rogerstg]

AFAIK shadow correction is only applied to jpeg, but highlight correction affects the raw file.

I just tried to do a test, but realized quickly that whatever it does leaves almost no trace in the EXIF and that I would need a well-controlled setup to do a reasonable test.

Thanks for the help. I think I'll just turn them off. I'd rather pick and choose when I want to protect highlights or let them wash out.

[mikesbike]

I have mine left at default. Perhaps there is a way to set it to "off" normally when shooting RAW files, but then by using one of the user modes for a preset, have it switched to "auto" and jpeg output together, so you could just turn one knob when you want to shoot jpegs, where it might be most helpful. I have yet to use these "user" presets, so I don't know if this can be set up. Maybe via the KP's 2nd and 3rd top dials ?

[rogerstg]

I have mine left at default. Perhaps there is a way to set it to "off" normally when shooting RAW files, but then by using one of the user modes for a preset, have it switched to "auto" and jpeg output together, so you could just turn one knob when you want to shoot jpegs, where it might be most helpful. I have yet to use these "user" presets, so I don't know if this can be set up. Maybe via the KP's 2nd and 3rd top dials ?

That's a great idea, but IIRC, that's not a setting saved by user mode. I'll check when I have my camera handy.