EV compensation

Plentax · 04-29-2013, 04:23 AM

Thanks KerrowDown for the remark about JPGs.

Yes, this is a common misunderstanding. The white balance, noise reduction, display bright/dark area warning and a lot of other features are only valid for JPGs and not for RAW/DNG. What you see on the PC screen with DNG depends of course heavily on the RAW-processor and monitor calibration. I used both CaptureOne (C1) and LightRoom (LR) for my DNGs from K-30, but had to give up with C1, because the colors are displayed terribly wrong . PhaseOne is not able since summer 2012 to provide any support in C1 for DNGs from K-30.

Regarding histogram shape, I am not yet sure (not enough experience) about the difference of K-30 and LR histogram. LR does show of course the DNG histogram, but what is shown on the K-30 rear display? I assume the JPG histogram, isn't it? And this histogram with its dark/bright warnings is certainly only a rough estimation for real DNG histogram.

Regards, Peter

Last edited by Plentax; 04-29-2013 at 06:07 AM.

no694terry · 04-29-2013, 07:14 AM

i want to learn more about the histogram. I have tried calibrating monitor but unsure of the best way to do it.

Plentax · 04-29-2013, 09:10 AM

Originally posted by no694terry

i want to learn more about the histogram. I have tried calibrating monitor but unsure of the best way to do it.

The histogram is only a helpful characteristic of brightness distribution inside an image. You can display histogram also for only R,G or B color to identify the statistical distribution of colors. If there is nothing on the left (dark) or right (bright) side of histogram you have no dark or bright colors in your image. If you have too much on the left or right, you have to much darkness or brightness in your image. Depending on the real content of your image, this statistical distribution is wanted or unwanted and you can correct this in the photo/raw editor or better already during photo shooting. With the histogram before/after shape you can also see clearly what a photo editors is doing on your image.

Reliable calibration of a monitor is only possible with specific measurement equipment and software. This is not very expensive, but worth the price, because you can trust your image manipulations much more and only with a calibrated monitor. I have done all my monitor, TV set and projector calibrations with Spyder 3. You can try to do a very rough calibration with popular test pictures alone, but this cannot compete at all with a good calibration based on measurement.

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04-29-2013, 04:23 AM	#16
Plentax Forum Member Join Date: Aug 2012 Photos: Albums Posts: 51	Thanks KerrowDown for the remark about JPGs. Yes, this is a common misunderstanding. The white balance, noise reduction, display bright/dark area warning and a lot of other features are only valid for JPGs and not for RAW/DNG. What you see on the PC screen with DNG depends of course heavily on the RAW-processor and monitor calibration. I used both CaptureOne (C1) and LightRoom (LR) for my DNGs from K-30, but had to give up with C1, because the colors are displayed terribly wrong . PhaseOne is not able since summer 2012 to provide any support in C1 for DNGs from K-30. Regarding histogram shape, I am not yet sure (not enough experience) about the difference of K-30 and LR histogram. LR does show of course the DNG histogram, but what is shown on the K-30 rear display? I assume the JPG histogram, isn't it? And this histogram with its dark/bright warnings is certainly only a rough estimation for real DNG histogram. Regards, Peter Last edited by Plentax; 04-29-2013 at 06:07 AM.

04-29-2013, 07:14 AM	#17
no694terry Veteran Member Join Date: Dec 2011 Photos: Gallery \| Albums Posts: 388 Original Poster	i want to learn more about the histogram. I have tried calibrating monitor but unsure of the best way to do it.

04-29-2013, 09:10 AM	#18
Plentax Forum Member Join Date: Aug 2012 Photos: Albums Posts: 51	Originally posted by no694terry i want to learn more about the histogram. I have tried calibrating monitor but unsure of the best way to do it. The histogram is only a helpful characteristic of brightness distribution inside an image. You can display histogram also for only R,G or B color to identify the statistical distribution of colors. If there is nothing on the left (dark) or right (bright) side of histogram you have no dark or bright colors in your image. If you have too much on the left or right, you have to much darkness or brightness in your image. Depending on the real content of your image, this statistical distribution is wanted or unwanted and you can correct this in the photo/raw editor or better already during photo shooting. With the histogram before/after shape you can also see clearly what a photo editors is doing on your image. Reliable calibration of a monitor is only possible with specific measurement equipment and software. This is not very expensive, but worth the price, because you can trust your image manipulations much more and only with a calibrated monitor. I have done all my monitor, TV set and projector calibrations with Spyder 3. You can try to do a very rough calibration with popular test pictures alone, but this cannot compete at all with a good calibration based on measurement.