# Set actual value of temperature in local adjustment preset



## gregreese (Nov 8, 2015)

In LR CC, when making a local-adjustment develop preset, how can I set the actual temperature? The slider only goes from -100 to +100, which I assume is an offset to the overall temperature setting. When making a regular (global) develop setting, the slider does let you enter the actual temperature.
Thanks.
Greg Reese


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## clee01l (Nov 8, 2015)

The global color temperature of the image has been set previously.  The local adjustment brush will only give you relative adjustment from the value of the pixels being affected. That is why you get +100 to -100 on the scale.

If you import a JPEG, the color temperature has been set in the camera. JPEG Global adjustments are also on a relative scale.


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## Hoggy (Nov 8, 2015)

Except I don't think the numbers have a 1:1 relationship, do they?  IOW, +100 isn't just 100K warmer.  At least it didn't _seem_ that way when I just tested it.  Seems like it's relative from the global temp, up to the end of the shown scale.

EDIT:  ...  ok, maybe not to the end of the scale.  I just set the global to 50000 - +100 didn't do anything, -100 didn't bring it all the way to the other side, either.  I had to duplicate the adjusmtent several times to cool it towards the other end.  So I don't know exactly what the scaling is.
(That's been a back-burner question of mine for quite a while.)


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## clee01l (Nov 9, 2015)

I can't say what the scaling is either, but I have a guess.  The temperature range is from 2000˚K to 50000˚K   This is 48000˚K range and can be divided up into 200 units (-100 to +100) Making each unit about 240˚K.  If you set the color temp of the RAW to 50000˚K, a brush set to +100 won't exceed the maximum, but the same brush set to -100  might lower the color temperature to 47600˚K.  Not a perceivable difference  perhaps. 
I did of your test setting the color to 50000˚K and then paint a temperature brush over it of -100  Not much apparent difference.  However, if you reverse the temperature to 2000˚K and change the brush to +100 to can see a significant difference.  The brush area is nearly normal looking.  
Also to need to set the Flow on the brush to 100 in all instances.


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## Johan Elzenga (Nov 9, 2015)

Hi Cletus, not that it really matters, but temperature in Kelvin is not (written) in degrees. It's 50000 K, not 50000˚K. See https://en.wikipedia.org/wiki/Degree_symbol


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## clee01l (Nov 9, 2015)

JohanElzenga said:


> Hi Cletus, not that it really matters, but temperature in Kelvin is not (written) in degrees. It's 50000 K, not 50000˚K. See https://en.wikipedia.org/wiki/Degree_symbol





> Since 1967 it has been known simply as the kelvin, with symbol K (without a degree symbol)


I am afraid I predate 1967.  So, it's not wrong, just obsolete as am I.


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## Johan Elzenga (Nov 9, 2015)

I predate 1967 too, by 13 years.


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## Jim Wilde (Nov 9, 2015)

Youngster!!


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## clee01l (Nov 9, 2015)

JohanElzenga said:


> I predate 1967 too, by 13 years.


By 1967, I had finished all go my Physics requirements.  So, Kelvin never came up in conversation  after that until I started learning about White Balance and photos.


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