M8 IR differences Raw vs Jpg

[innerimager]

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OK, I couldn't stand it, I opened the M8 box. My dealer had said I could take a few shots with it all along, I just didn't want to tempt myself, but I couldn't just send it back without taking a single shot. I took images in DNG + JPG, set a Tungsten WB, and found that often the JPG was essentially fine, while the DNG showed substantial IR contamination, as this example shows. This means that Leica has applied a profile in the JPG conversion that at least at times works well. I suspect it is very sensitive to WB being accurate, so JPG's shot on Auto WB under tungsten, which is WAY off in the M8, will look bad. But, maybe, if WB is close to accurate, Leica has a profile that works well enough that they, perhaps rightly, thought the IR problem could be solved in software. So here's an example-

 

JPG in Camera

DNG opened in ACR, all settings untouched and converted to JPG

The color of the love seat is correct in the camera JPG, quite contaminated in the DNG conversion. Likewise the colors in the emblem are correct in the JPG and contaminated in the DNG.

If this has been seen already, forgive me.

I'm going to sleep now.....Peter

[mike prevette]

It's possible what we are seeing here just has to do with the saturation level of the DNG profile vs. the one leica is using in camera for the jpg.

 

points to you for even thinking about not opening the box

_mike

[innerimager]

No Mike, it's more than that. here's another example, of a poorly focuses noctilux F1 shot. First the JPG, then the DNG. That pot is brown, and look at all the magenta spill in the background in the DNG absent entirely in the Jpg.....Peter

[andyyl]

Hello,

 

If I compare both pairs of images I note that the DNGs are both much too reddish, so both of you did perform the WB in theRAW conversion correctly.

Please check inthe first image the white wall,and in the second the silver/dray radio on the oven.

Then the pot and and the couch both will have the same color as in the resp. JPEGs.

 

Andreas

[adan]

Peter: You said, in the caption for the DNG version of the jacket photo, "DNG opened in ACR, all settings untouched and converted to JPG"

 

ACR does not have a calibrated profile for the M8. There is no way to trust the ACR colors until one has done a calibration with a Macbeth/Gretag ColorChecker.

 

As I did here:

 

http://www.leica-camera-user.com/digital-forum/9330-18-hours-m8-pix-discoveries.html

 

The calibration settings I ended up with cut way back on blue and red saturation (and guess which colors make up magenta?) as well as adding some green to the shadow tint (and guess which color is the opposite of magenta, and as a shadow tint will have its greatest effect on blacks and dark colors?). It also took a lot of magenta out of the blues and reds, shifting them (respectively) towards cyan and yellow.

 

A good profile will not remove all of the effect of the IR contamination magentas - but the uncalibrated ACR handling of M8 DNG files is very magenta-biased in its own right, which just makes things worse.

[carstenw]

This could also be partly due to the iffy white balancing which the M8 does in firmware <= 1.06. What happens if you set the white balance manually in these shots?

[Jamie Roberts]

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I just have to say that this is a great example of how one profile compares with another from a firmware perspective.

 

Usually, when you have a great out of the camera profile, the results are reversed: in-camera JPEGs don't look as good as RAW files.

 

But as Michael Tapes used to say, you always shoot RAW anyway with digital; you only decide who finally creates the JPEG.... you or the camera

 

Glad to hear, too, that PS ACR works with some adjusting. Looks like all the RAW converters currently have this one wrong (but that's not surprising since it's so new).

 

Carsten--welcome aboard WB is crucial to getting this right (always is with digital). If I was shooting JPEG, I'd be setting a custom WB and use that till the light changes (though, in truth, I haven't tried that at all with the M8, because I've been shooting RAW).

[innerimager]

I just have to say that this is a great example of how one profile compares with another from a firmware perspective.

WB is crucial to getting this right (always is with digital). If I was shooting JPEG, I'd be setting a custom WB and use that till the light changes (though, in truth, I haven't tried that at all with the M8, because I've been shooting RAW).

 

Yes the WB is a big variable. Whatever bias in the RBG channels set by an incorrect WB is compounded by the false IR color. My first few shots used Auto WB and the Jpgs were as bad as the Dng's. These were Tungsten WB, and Leica's in camera profile was able to correct the false colors pretty well, while a generic profile in ACR did nothing to the false colors, just passed them on.

 

If I were shooting the M8 (and I may well keep it now), until the Raw converter profiles are ready, I'd at least shoot Raw+Jpg, and use a color meter to apply the correct K value for WB. best...Peter