What Color Space Do I Use? (Part 1)
Question:
I've been trying to come to terms with color management and working color space. What color space do you use, and which is best?
Answer:
Short Answer: I use sRGB. There is not really a 'best' color space, though I find sRGB best and most consistent for what I do.
Color spaces are confusing to most people, and become a heady topic for debate. It is good to know at least the basics before making a choice between which to use. I have my preferences after 15 years of working with digital color, and they have changed with the technology...but let's look at some concepts. In part two of this entry, I'll add in a discussion of why I choose the color management settings that I do.
The "Best" Way...
Working color spaces have trade-offs and advantages, or there wouldn't be choices. If there were a 'best way' to handle color it would likely be handled automatically (e.g., Adobe would put best practices in place programmatically). I consider sRGB as a "realist" color space. It is based on standard monitor display--you deal with colors that can be safely seen on screen (16 million of them in 8-bit). AdobeRGB portends to make color that is better apt for printing--it extends beyond the model of colors you can safely see on your monitor to map colors available in print that are not 'seen' on a monitor (also 16-million in 8-bit). The fallback of sRGB is that it doesn't have a representation of a broader color set. AdobeRGB is said to have a 'broader' color model, but most people don't know what that means: to me it means the set number of colors is mapped differently--not that there are more or even necessarily 'better' colors. People do a LOT of arguing about the potential advantages of using either sRGB or AdobeRGB as a working color space.
In a perfectly theoretical arena, you'd want to work with images in optimal conditions: colors that you would be able to see on screen would readily translate into print. There-in lies the rub. RGB and CMYK reproduce different color sets. RGB is color theory based on light where red, green and blue make up all the potential colors on your monitor; CMYK is color theory based on ABSORPTION of light, as inks of cyan, magenta, yellow and black that represent all colors in print. While slightly over-simplifying here, RGB favors reds, greens and blues to the slight failing in representation of cyan, magenta and yellow. CMYK favors cyan, magenta and yellow with a failure in being able to represent the brightest reds, greens and blues. Though CMYK has an additional 'color' (black), it does not add representation to the theoretical space: black is added to compensate for the inability of ink to be perfectly efficient in absorption...black helps compensate the CMY model so that it will have a full dynamic range. Such things as the physical properties of the ink, paper, and available light will contribute to the lack of perfect performance in ink absorption. All this really means is: the colors represented by CMYK and RGB are different, and what you see on your monitor is not the same as what printing in CMYK can represent.
Making Compensation
There are all sorts of ways that technology tries to compensate for the difference, such as providing printers with additional colors, or allowing translation using color mappings and embedded profiles. Adobe claims that AdobeRGB is a better model in representing the potential of CMYK, because it maps to more CMYK colors than sRGB. It is generally argued that AdobeRGB is more geared to printing images because of its mapping to print colors and that sRGB is better on screen based on its mapping for colors associated with monitor display. The idea is intreguing, in that the color sets promise to allow you to do more direct correction of assoviated colors optimized for a particular use. Yet the reality is, just like RGB and CMYK have different colors, you can't see AdobeRGB color with reliability on an RGB screen...it becomes a conundrum. One solution used to lie in converting to CMYK and that works for those doing certain types of printing, but is really not as helpful for most people who just send images to a service, or run them out on a home inkjet.
There are practice of using color profiles (and embedding them in your images) helps describe the color in an image to different devices, acting like a type of translator. If you work in a color space and place a profile in your image, the THEORY is that you will be able to send that file to other devices (printers, monitors) that will recognize the color mapping and interpret it correctly. Once the device can interpret the color, in theory it shouldn't matter what color space it is in: If the colors can be translated and interpreted, the results should have a reasonable chance of matching.
The problem becomes defining what is supposed to be matched. If you are in sRGB, and you match what it looks like on screen, that may make sense, but using Adobe RGB if you match what is on screen you aren't taking advantage of the broader color space; if you match what is not on screen, you can't ever see what you are adjusting. But the problems just start there whether you use sRGB or AdobeRGB. Add to the problem the fact that not everything prints as CMYK. If AdobeRGB gives you better CMYK and you print to a light process or display images on the web, it may not really offer an advantage. Another issue is the reality that color management theory doesn't always work in the real world: profiles can get dropped (intentionally or not) or remain unused by devices. When you consider the world might not be perfect, you have a better picture of the real mess and why color management becomes such an issue for debate. One person swears by how they achieved success in their workflow and another opposes as they achieved success a completely different way. The fact is that they may both be right, either for the right or wrong reasons.
And the Answer Is?
So the answer to the question of whether you should use one working space or another is: either sRGB or AdobeRGB can work...but you need to accept the advantages and disadvantages of either workflow. Which will work better for you may be answered by taking a look at your workflow as an entire process. That is, based on how you work with images, your choices for what is best in adopting a workflow should be based on what you do with images, rather than what someone else does--whether or not they do it with success. In the next entry we'll look at the workflow I use and why I've made the choices I have to give you a peek into a considered workflow.
POSTSCRIPT
I've just finished writing my new book The Adobe Photoshop Layers Book. It will be out in July of 2007.
I've been trying to come to terms with color management and working color space. What color space do you use, and which is best?
Answer:
Short Answer: I use sRGB. There is not really a 'best' color space, though I find sRGB best and most consistent for what I do.
Color spaces are confusing to most people, and become a heady topic for debate. It is good to know at least the basics before making a choice between which to use. I have my preferences after 15 years of working with digital color, and they have changed with the technology...but let's look at some concepts. In part two of this entry, I'll add in a discussion of why I choose the color management settings that I do.
The "Best" Way...
Working color spaces have trade-offs and advantages, or there wouldn't be choices. If there were a 'best way' to handle color it would likely be handled automatically (e.g., Adobe would put best practices in place programmatically). I consider sRGB as a "realist" color space. It is based on standard monitor display--you deal with colors that can be safely seen on screen (16 million of them in 8-bit). AdobeRGB portends to make color that is better apt for printing--it extends beyond the model of colors you can safely see on your monitor to map colors available in print that are not 'seen' on a monitor (also 16-million in 8-bit). The fallback of sRGB is that it doesn't have a representation of a broader color set. AdobeRGB is said to have a 'broader' color model, but most people don't know what that means: to me it means the set number of colors is mapped differently--not that there are more or even necessarily 'better' colors. People do a LOT of arguing about the potential advantages of using either sRGB or AdobeRGB as a working color space.
In a perfectly theoretical arena, you'd want to work with images in optimal conditions: colors that you would be able to see on screen would readily translate into print. There-in lies the rub. RGB and CMYK reproduce different color sets. RGB is color theory based on light where red, green and blue make up all the potential colors on your monitor; CMYK is color theory based on ABSORPTION of light, as inks of cyan, magenta, yellow and black that represent all colors in print. While slightly over-simplifying here, RGB favors reds, greens and blues to the slight failing in representation of cyan, magenta and yellow. CMYK favors cyan, magenta and yellow with a failure in being able to represent the brightest reds, greens and blues. Though CMYK has an additional 'color' (black), it does not add representation to the theoretical space: black is added to compensate for the inability of ink to be perfectly efficient in absorption...black helps compensate the CMY model so that it will have a full dynamic range. Such things as the physical properties of the ink, paper, and available light will contribute to the lack of perfect performance in ink absorption. All this really means is: the colors represented by CMYK and RGB are different, and what you see on your monitor is not the same as what printing in CMYK can represent.
Making Compensation
There are all sorts of ways that technology tries to compensate for the difference, such as providing printers with additional colors, or allowing translation using color mappings and embedded profiles. Adobe claims that AdobeRGB is a better model in representing the potential of CMYK, because it maps to more CMYK colors than sRGB. It is generally argued that AdobeRGB is more geared to printing images because of its mapping to print colors and that sRGB is better on screen based on its mapping for colors associated with monitor display. The idea is intreguing, in that the color sets promise to allow you to do more direct correction of assoviated colors optimized for a particular use. Yet the reality is, just like RGB and CMYK have different colors, you can't see AdobeRGB color with reliability on an RGB screen...it becomes a conundrum. One solution used to lie in converting to CMYK and that works for those doing certain types of printing, but is really not as helpful for most people who just send images to a service, or run them out on a home inkjet.
There are practice of using color profiles (and embedding them in your images) helps describe the color in an image to different devices, acting like a type of translator. If you work in a color space and place a profile in your image, the THEORY is that you will be able to send that file to other devices (printers, monitors) that will recognize the color mapping and interpret it correctly. Once the device can interpret the color, in theory it shouldn't matter what color space it is in: If the colors can be translated and interpreted, the results should have a reasonable chance of matching.
The problem becomes defining what is supposed to be matched. If you are in sRGB, and you match what it looks like on screen, that may make sense, but using Adobe RGB if you match what is on screen you aren't taking advantage of the broader color space; if you match what is not on screen, you can't ever see what you are adjusting. But the problems just start there whether you use sRGB or AdobeRGB. Add to the problem the fact that not everything prints as CMYK. If AdobeRGB gives you better CMYK and you print to a light process or display images on the web, it may not really offer an advantage. Another issue is the reality that color management theory doesn't always work in the real world: profiles can get dropped (intentionally or not) or remain unused by devices. When you consider the world might not be perfect, you have a better picture of the real mess and why color management becomes such an issue for debate. One person swears by how they achieved success in their workflow and another opposes as they achieved success a completely different way. The fact is that they may both be right, either for the right or wrong reasons.
And the Answer Is?
So the answer to the question of whether you should use one working space or another is: either sRGB or AdobeRGB can work...but you need to accept the advantages and disadvantages of either workflow. Which will work better for you may be answered by taking a look at your workflow as an entire process. That is, based on how you work with images, your choices for what is best in adopting a workflow should be based on what you do with images, rather than what someone else does--whether or not they do it with success. In the next entry we'll look at the workflow I use and why I've made the choices I have to give you a peek into a considered workflow.
POSTSCRIPT
I've just finished writing my new book The Adobe Photoshop Layers Book. It will be out in July of 2007.
Labels: color management, Elements, image editing, Photoshop, workflow
