Unveiling M11?

[MikeMyers]

Advertisement (gone after registration)

I know, that's why I added "not sure if this would work with digital".   I never thought about this before, and to be honest, I have no desire to go looking at pixels anyway.

Let's assume that @Adam Bonn is correct, and his profile is more accurate than the profile from Adobe.  Then what?

Edited December 22, 2021 by MikeMyers

[Adam Bonn]

What I did is follow the DNG spec

https://www.adobe.com/content/dam/acom/en/products/photoshop/pdfs/dng_spec.pdf

Quote

If two calibrations are included, then it is recommended that one of the calibrations be for a
low color temperature illuminant (e.g., Standard-A) and the second calibration illuminant be
for a higher color temperature illuminant (e.g., D55 or D65). This combination has been found
to work well for a wide range of real-world digital camera images.
 

So Leica does this part above (using D65)

However, the DNG spec goes on to say

Quote

The use of the forward matrix tags is recommended for two reasons. First, it allows the camera
profile creator to control the chromatic adaptation algorithm used to convert between the
calibration illuminant and D50. Second, it causes the white balance adjustment (if the user
white balance does not match the calibration illuminant) to be done by scaling the camera
coordinates rather than by adapting the resulting XYZ values, which has been found to work
better in extreme cases.
 

Leica decide not to use forward matrices (despite Adobe's recommendations)

But the DNG spec tells us how to make them

Quote

If the ForwardMatrix tags are not included in the camera profile:
1. First, invert the XYZtoCamera matrix.
If n = 3, this is:
CameraToXYZ = Inverse (XYZtoCamera)
If n > 3, and the reduction matrix tags are included, then:
CameraToXYZ = Inverse (RM * XYZtoCamera) * RM
Otherwise:
CameraToXYZ = PseudoInverse (XYZtoCamera)
2. The white balanced transform is computed:
CameraToXYZ_D50 = CA * CameraToXYZ
CA, above, is a chromatic adaptation matrix that maps from the white balance xy value to
the D50 white point. The recommended method for computing this chromatic adaptation
matrix is to use the linear Bradford algorithm.

The maths for which I posted already.

 

1 hour ago, adli said:

 

So, basically, you have changed the white point to a cooler value...

 

So I haven't changed the white point (or the white balance), I've merely given LR the information it needs to map from the base calibration to the colour temperature that adobe uses (D50)

worth mentioning:

1) when adobe write 'user' white balance they mean camera selected WB

2) the DNG spec is aimed at camera manufacturers who wish to shoot DNG and RAW editor creators that wish to support it.

3) you can actually change the chromatic adaptation matrix 'on the fly' within LR (and I guess ACR) by using the camera calibration sliders, however then you're adjusting both at the same time and if you profile for them you can make one for each illuninant.

==============

I feel this has gone on long enough now, especially for the thread and sub forum topic.

If anyone has any serious questions and feels that I might be able to help them with their own profiling efforts, please inbox me - it's a busy week though! (and spoiler alert, just spring for Lumariver)

 

 

[Adam Bonn]

28 minutes ago, MikeMyers said:

Let's assume that @Adam Bonn is correct, and his profile is more accurate than the profile from Adobe.  Then what?

Alternatively, let's read what I said and see I said Leica Embedded profile and Adode DNG spec 🙂 (not profile from adobe)

Mike,

This is all LR/ACR centric stuff and you don't use those apps. Don't get sucked in.

I was asked to provide an example of how profiling can effect the editing and I did. Nothing more to see here.

[MikeMyers]

36 minutes ago, Adam Bonn said:

I was asked to provide an example of how profiling can effect the editing and I did. Nothing more to see here.

OK, thanks!!  I'm not using adobe, and have no plans to do so, but who knows what the future might bring.  Hopefully the way the M11 is released provides everyone with what they need.

When it comes to profiles and profiling, are all the Leica M10 cameras, and the new M11 identical?  With the differences in sensor resolution, will that create changes in how they deal with color?

[Adam Bonn]

3 minutes ago, MikeMyers said:

OK, thanks!!  I'm not using adobe, and have no plans to do so, but who knows what the future might bring.  Hopefully the way the M11 is released provides everyone with what they need.

When it comes to profiles and profiling, are all the Leica M10 cameras, and the new M11 identical?  With the differences in sensor resolution, will that create changes in how they deal with color?

I've never seen an embedded Leica profile that's any more than just two colour matrices, but who knows what  they might decide to do in the future 

For comparison an adobe profile is 

2 colour matrices 

2 forward matrices 

2 HSD tables 

And a LUT

(And that's before we get into these new fangled 3D LUT things they're using now too beef up their standard profiles) 

[setuporg]

Ah, always illuminating to stop by an M11-coming thread after a 100 replies and always learn something new, like a DNG spec!

[algrove]

Advertisement (gone after registration)

So 7 Jan in France and 13 Jan is US. That makes no sense since the cat will be out of the bag well before 13 Jan.

[SrMi]

3 hours ago, algrove said:

So 7 Jan in France and 13 Jan is US. That makes no sense since the cat will be out of the bag well before 13 Jan.

See post #172 (1/7 is only for dealers).

[adli]

14 hours ago, Adam Bonn said:

 

 

 

So I haven't changed the white point (or the white balance), I've merely given LR the information it needs to map from the base calibration to the colour temperature that adobe uses (D50)

 

 

Still moves the white point.

 

[Adam Bonn]

10 minutes ago, adli said:

 

Still moves the white point.

 

white points are fixed coordinates the FM stops LR guessing the chromatic adaptation.

(and D50 is warner than D28, not cooler)

[Chun Chang]

On 12/20/2021 at 12:31 AM, evikne said:

I understand why Leica in 2012 just wanted to call all their M models “M”. 😄

Would simplify things yes.  Or Mmmmmmmmmmmmm as in delicious 😆

[adli]

6 hours ago, Adam Bonn said:

white points are fixed coordinates the FM stops LR guessing the chromatic adaptation.

(and D50 is warner than D28, not cooler)

 

You wrote "The image on the right has the exact same profile, the exact same as shot WB, but I've used the maths above (which incidentally is the Bradford D50 Chromatic Adaptation, as recommended in the DNG spec) to create a forward matrix that maps the StdA colormatrix to the D50 white point."

I read this as mapping from A to D50.

 

[setuporg]

On 12/15/2021 at 11:31 AM, SrMi said:

The sensel size does not matter much.

Just like a sensei size.

[setuporg]

Note to Leica: if you ask us to watch this space, next time please actually launch 🚀 in this space.:)