LAB Colour or Color

[russellsnr]

Hi,Trying to get my head round working in LAB. I have searched for anything to do with working in LAB in the forum but the search engine says the word LAB is to short and if I add Colour or Color it comes up with pages with one of those two spellings, same thing if I type in Photoshop LAB loads of info on P/S.
So question is do many of you who have P/S work with LAB and if so do you find it a better option when it comes to colour/color in an image rather than working in RGB or CMYK?
Thanks
Russ

[Colin Southern]

Hi Russ,

I use it - and it's great once you get your head around it. Best way to learn it is to grab a copy of http://www.amazon.com/Photoshop-LAB-...7263503&sr=8-2

Cheers,

Colin

[Polar01]

Russ: have no idea what LAB is. RGB (red,green,blue) are the three colours that are used that you see on your's or any other monitor/screen, CMYK (cyan,maganta,yellow, black) are the colours that are used in the printing process. Sometimes is helps others, if you post in your info, where you are from as this forum is world wide. Sometimes a word or pharse that is common to you, someone else will have no idea what you mean. Example the word colour in Canada, United Kingdom and other English speaking countries it is spelled with a "u" in the United States they dropped the "u", thus color. Maybe you could explain to me and other if they do not know what LAB is.

Allan

[russellsnr]

Russ: have no idea what LAB is. RGB (red,green,blue) are the three colours that are used that you see on your's or any other monitor/screen, CMYK (cyan,maganta,yellow, black) are the colours that are used in the printing process. Sometimes is helps others, if you post in your info, where you are from as this forum is world wide. Sometimes a word or pharse that is common to you, someone else will have no idea what you mean. Example the word colour in Canada, United Kingdom and other English speaking countries it is spelled with a "u" in the United States they dropped the "u", thus color. Maybe you could explain to me and other if they do not know what LAB is.

Allan

Hi Allan, If you read http://en.wikipedia.org/wiki/Lab_color_space it will explain it better than I can ever do in a few words, what I will say is that LAB is not short for laboratory it is spoken like R G B so L A B It can be found in P/S under image/mode/ lab color
Thank you for the responce to the question.
Russ

[russellsnr]

Hi Russ,

I use it - and it's great once you get your head around it. Best way to learn it is to grab a copy of http://www.amazon.com/Photoshop-LAB-...7263503&sr=8-2

Cheers,

Colin

Hi, Many thanks Colin and I will get my head round it but may take some time
Russ

[Andrew1]

The best simplest one I've come across and I keep it handy for refreshers. I would suggest you read it all the first time through, don't skip anything even in the basics. It's not as long as it looks. (OK you can skip the more advanced calculations if you're not interested.) Let me know if this works for you and helps make the concepts of colour come together.

http://www.hunterlab.com/pdf/color.pdf

[Colin Southern]

Hi, Many thanks Colin and I will get my head round it but may take some time
Russ

Just get the book

In summary, LAB separates an image into a Luminance channel (think "greyscale" and you'll be close enough), and 2 colour opponancy channels (A & B) (green-magenta & blue-yellow). In a nutshell, our brain processes what the eyes feed it in LAB.

It's not ideal or all kinds of images, but great for bringing out ("driving apart") subtle colour variations in landscapes without necessarily boosting global saturation (just add a curves layer and evenly steepen the slope of the A or B channel (or both) and watch what happens).

[Shadowman]

Go to

www.xrite.com

They have a series of densitometers and screen calibrators that are used in the paint and color matching industry. You will also find a series of lessons on color terminology. One thing you will find is that the art of color recognition is very thorough, inspectors are tested on a yearly basis and if they fail the eye exam, they can no longer serve as quality control inspectors. L.a.b. is a measurement of color where the "L" measures from 0 to 100 levels of black (0) to white (100), the "a" measures from -10 to 10 the colors red to green, with green being negative, and "b" measures yellow to blue on a scale of =10 to 10 with blue being negative. Visual color intepretations by computer never really match what the human eye sees unless the L*a*b* values are at the end of the scale. Usually the computer will give you a brownish/grey visual interpretation of what your eye sees as a vivid color.