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NikonErik · 12-19-2007

Each method for reproduing colors does it in a different way, right?

(All of The following may not apply to Raw capture)

From the beginning . . .

Every imaging device has a signature look we call a profile. When you capture an image and write a jpeg, your camera has it's profile. That is to say that it re-produces the colors it captured in it's own way. Miuch like a Fujifilm vs. Kodak film comparison, Nikon and Canon each have their looks to them. Some of you (not me) could probably guess the brand of the camera just by looking at the image.

To make things more complicated, some cameras have more than one "box of crayons" or gamut with which to interpret the sensor data when creating the file. Regardless of which gamut you use, someone looking to work as smartly as possible will consider where the the file goes next.

You may have noticed that ACR, and LR have camera calibration control panels. This is how photographers and studios dealing with multiple cameras and camera systems can get similar color reproduction when importing the catalogs.

The colorimeter you used to calibrate the monitor sent standard RGB recipes (standard colors) to the monitor. The optical colorimeter looked at your monitor during this process and decided in a precise manner how "off" your monitor was when displaying these colors. The software then creates a conversion index profile for that monitor. This way RGB recipe 46, 185, 108 looks like THAT COLOR when displayed on your screen. Without calibration 46, 185, 108 could look like 46, 185, 164 - which is blue shifted, but only subtly so. If your monitor is more blue shifted, or cooler than than your commercial clients monitor, then this could easily be a reason they are getting on your back because their products are the wrong color in your proofs. It could be why Bridezilla is calling you because her $10,000 Ivory dress looks Virgin White in her proof set. (true stories - I calibrated their monitors for them and voila!)

Okay, now you have a profile that looks at your specific monitors to ensure that the colors optically look the way they are supposed to. Next you get to have all of the fun with your software and make things look fine and dandy!

Folks with multiple monitors my want to use a system that is specifically designed to ensure that both monitors make the colors look the same across both of them.

The next problem you face is when you consider that the printer you use will also use its own unique recipe to reproduce the colors. We can only hope that they profile their machines to ensure that 46, 185, 108 looks correct on their paper when the images are printed.

Here's the kicker: Our monitors produce A LOT more colors, particularly more saturated colors that most printers can!

Have a look at this:

The term "Gamut" refers to what I like to describe as the "box of crayons" that's available to your image reproduction device. No two devices have the same "box." Crayola's "blue" crayon is different, I am sure, than Rose Art's "blue". The range of colors a reproduction system can create is mapped on a 3-D grid, or 3-D space.

Below you see two 3-D Gamut maps centered on each other on a 3-axis space based on Lab color (as opposed to RGB). Lab color space was designed to represent colors that is more like the way we see. In Lab space, the vertical axis represents Luminosity (white to black). Another axis represents the "a" axis which is the range of colors between green and red. Finally the 'b" axis which is the range between yellow and blue. See this HP ColorSpan page for a cool graphic and simple explanation.

I rotated the graph to show top and sides . . .

In the above screen captures I am comparing my calibrated monitors profile with the smaller one that Costco can reproduce. The gray represents my (pretty good) monitors capabilities. Notice the Costco gamut resides almost entirely inside of the monitors gamut-space.

By the way, the best machine at White House Custom Color, one of America's most advertised "high end" service bureaus (I love to use these guys) has a gamut only a wee-bit broader in the reds than Costco. I have a macro image of a rose that is out of Gamut for most labs that I'd like to use to print the image. Oh well, I'll enjoy it on the screen!

If it just occurred to you that your images color range may not be getting printed, then you are catching on!

What do you do??

Read on . . .

12-19-2007	#2 (permalink)
NikonErik Registered User Join Date: Nov 2007 Location: Long Island, NY Posts: 119	Each method for reproduing colors does it in a different way, right? (All of The following may not apply to Raw capture) From the beginning . . . Every imaging device has a signature look we call a profile. When you capture an image and write a jpeg, your camera has it's profile. That is to say that it re-produces the colors it captured in it's own way. Miuch like a Fujifilm vs. Kodak film comparison, Nikon and Canon each have their looks to them. Some of you (not me) could probably guess the brand of the camera just by looking at the image. To make things more complicated, some cameras have more than one "box of crayons" or gamut with which to interpret the sensor data when creating the file. Regardless of which gamut you use, someone looking to work as smartly as possible will consider where the the file goes next. You may have noticed that ACR, and LR have camera calibration control panels. This is how photographers and studios dealing with multiple cameras and camera systems can get similar color reproduction when importing the catalogs. The colorimeter you used to calibrate the monitor sent standard RGB recipes (standard colors) to the monitor. The optical colorimeter looked at your monitor during this process and decided in a precise manner how "off" your monitor was when displaying these colors. The software then creates a conversion index profile for that monitor. This way RGB recipe 46, 185, 108 looks like THAT COLOR when displayed on your screen. Without calibration 46, 185, 108 could look like 46, 185, 164 - which is blue shifted, but only subtly so. If your monitor is more blue shifted, or cooler than than your commercial clients monitor, then this could easily be a reason they are getting on your back because their products are the wrong color in your proofs. It could be why Bridezilla is calling you because her $10,000 Ivory dress looks Virgin White in her proof set. (true stories - I calibrated their monitors for them and voila!) Okay, now you have a profile that looks at your specific monitors to ensure that the colors optically look the way they are supposed to. Next you get to have all of the fun with your software and make things look fine and dandy! Folks with multiple monitors my want to use a system that is specifically designed to ensure that both monitors make the colors look the same across both of them. The next problem you face is when you consider that the printer you use will also use its own unique recipe to reproduce the colors. We can only hope that they profile their machines to ensure that 46, 185, 108 looks correct on their paper when the images are printed. Here's the kicker: Our monitors produce A LOT more colors, particularly more saturated colors that most printers can! Have a look at this: The term "Gamut" refers to what I like to describe as the "box of crayons" that's available to your image reproduction device. No two devices have the same "box." Crayola's "blue" crayon is different, I am sure, than Rose Art's "blue". The range of colors a reproduction system can create is mapped on a 3-D grid, or 3-D space. Below you see two 3-D Gamut maps centered on each other on a 3-axis space based on Lab color (as opposed to RGB). Lab color space was designed to represent colors that is more like the way we see. In Lab space, the vertical axis represents Luminosity (white to black). Another axis represents the "a" axis which is the range of colors between green and red. Finally the 'b" axis which is the range between yellow and blue. See this HP ColorSpan page for a cool graphic and simple explanation. I rotated the graph to show top and sides . . . In the above screen captures I am comparing my calibrated monitors profile with the smaller one that Costco can reproduce. The gray represents my (pretty good) monitors capabilities. Notice the Costco gamut resides almost entirely inside of the monitors gamut-space. By the way, the best machine at White House Custom Color, one of America's most advertised "high end" service bureaus (I love to use these guys) has a gamut only a wee-bit broader in the reds than Costco. I have a macro image of a rose that is out of Gamut for most labs that I'd like to use to print the image. Oh well, I'll enjoy it on the screen! If it just occurred to you that your images color range may not be getting printed, then you are catching on! What do you do?? Read on . . . __________________ There are always two people in every picture: the photographer and the viewer. ~Ansel Adams Last edited by NikonErik; 12-19-2007 at 12:45 AM.