Standardization of Color Temp Adjustments in Adobe CC

'What I am stating which should be clear in one word "Standardization"'

Just for clarity, Lightroom and ACR work exactly the same and, on raw files, use a Kelvin scale.

However, as D Fosse and Stephen point out, the camera raw filter, or Lightroom/ACR working on an already processed RGB file use a +/- numeric scale to further adjust the temp & tint. There is no requirement for an RGB image file to have the colour temperature in its metadata, therefore no way for an image processing application to know what the starting point of an RGB image, which could have been processed in any application or camera or even computer rendered,  is in order to use a Kelvin scale. Hence the +/- arbitary scale.

So there is no discrepency between applications.

Dave

@westdr1dw Here is the point:

There is nothing in the camera that measures the actual color of the light in the scene. There is no actual Kelvin number, just a compensation to produce a visually neutral result according to certain algorithms in the camera firmware.

Same thing in a raw processor. The raw file is just a data dump from the camera sensor, the photons that were recorded. There is no inherent information about the light in the scene.

So, the Kelvin number you read in LrC/ACR is the amount of compensation applied to produce a visually "neutral" result. The Kelvin scale is an appropriate parameter to refer to with raw files, because it corresponds to a normal range of light conditions in the photographed scene. But note that the Kelvin scale does not apply to LED or fluorescent.

In a rendered RGB file, all this is moot and irrelevant. The "temperature" you have set in the raw processor/camera is now baked into the RGB numbers. It's already done. An RGB file just is what it is. Obviously, you can still adjust along the blue/yellow axis, and you can call that "temperature" for convenience and to separate it from the green/magenta axis - but it doesn't make any sense to specify Kelvin numbers. Hence, a -100 to 100 scale is much more logical.

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@westdr1dw wrote:

I was not even aware of the differences between LrC, PS, and ACR.

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Again, can you please post comparative screenshots from LrC, ACR and Photoshop so that the forum can see exactly what features and differences you are comparing?

Stephen 

Your'e missing the point.

What I am stating which should be clear in one word "Standardization"

 However within a suite of apps you apply should have rules which are applicable to all apps within the suite. If you have one app which applies the measurment scale which is known in the scientific community as color temperature "Kelvin", why would you refer to it as +/- 100. What is this measuring?  When setting up studio lighting, the color temperature is based on Kelvin not on a +/- 100. ACR should use the same scale for color temperature as this is the unit of measurement. 

I don't use LrC, so I can't comment.

The Adobe Camera Raw plugin (ACR) raw processing engine is what powers raw development in LrC, so if they use different scales or terminology in the interface that must be cosmetic.

The Camera Raw Fillter (CRF) inside Photoshop is based on ACR, however, this can't process raw data and the temp/tint, exposure and other raw processing controls don't work the same on rendered data as they do on raw camera sensor data.

Photoshop is for processed/rendered data, so it doesn't work the same way as ACR. For example, many photographers think that the Exposure adjustment in Photoshop is for photographs in 8 or 16 BPC mode, however, it is designed for HDR 32 BPC imagery.

Can you post comparative screenshots from LrC, ACR and Photoshop so that the forum can see exactly what features and differences you are comparing?