What Colour Space Should I be Using

There are many Colour Spaces used in various industries, each with advantages and disadvantages. The main ones you will encounter in order of total gamut are:

• CMYK - Most Printers
• sRGB - Most cameras and screens
• DCI P3 - Modern Mac Screens
• AdobeRGB - High End Monitors and Pro Cameras
• ProPhoto - Not available on any Screen in commercial production

The Colour space you should be using depends on many things.

• The Camera you shoot with
• The Monitor you edit on
• The Types of images you work on
• What you intend to do with them

So which should you choose? It starts with the camera.

If your Camera supports RAW shooting then the colour space does not matter at the camera level as it will be set when imported to Lightroom or your program of choice. RAW mode ensures that your camera captures as much of the data as true as possible to its capabilities.

If you camera does not support RAW - then choosing the AdobeRGB Colour Space if possible for the generated Jpegs. If your camera does not offer a choice of Colour Space, then you should assume it is set to sRGB. If this is the case, the highest Colour Space you should use for editing is sRGB as there is not a lot of benefit to increase the Gamut.

But what if your Camera Supports RAW and/or AdobeRGB? Now it comes down to your monitor.

Most monitors for sale are only capable of displaying sRGB. Here at Art House, we use a variety of monitors for viewing images before printing.

• Dell UltraSharp U2713HM - Capable of 99% sRGB and 79% AdobeRGB (bought for $800)
• Dell UltraSharp U2711 - Capable of 100% sRGB and 96% AdobeRGB (bought for $1500)
• Eizo Colour Edge CG277W - Capable of 100% sRGB 99% AdobeRGB (bought for $3600)

All of these monitors are Calibrated on a regular basis to the same standards to ensure consistency. If your files are sRGB, they will look almost identical on all 3 of our monitors. If your files are in AdobeRGB they will look very different on the much cheaper Dell, but will look very similar on the more expensive Dell and Eizo.

If you have a modern Mac computer it is likely your screen has the ability to display the DCI-P3 Colour Space. The P3 Space is similar to AdobeRGB overall and you will only notice a difference in highly saturated images.

So depending on the monitor you edit on, you can use sRGB or AdobeRGB or DCI-P3.  

Regardless of the quality and gamut capabilities of your monitor, without regular calibration you may see incorrect colours. Screens wear out overtime, and the emitted light shifts ever so slightly, so if you are serious about colour consistency you should calibrate your screen on a monthly basis.

Next comes what types of images you work on and what you intend to do with them.

If your files are only ever going to be viewed on a screen, posted to the internet to be viewed around the world, it is safest to work in the highest Colour Space as dictated by your Camera and Monitor, but output your files in sRGB. This will ensure maximum compatibility and consistency with monitors and screens around the world. Be careful when doing this if you try to highly saturate your images in one of the "larger" colour spaces, as when outputting to sRGB some colours will be altered to fit within the new space. If you are "online only" with high saturation images, using sRGB from the start could be best.

If you are sending your files to be printed, the master files should again always be in the highest space available to you, but output to the specification required by the printing company. Here at Art House, we prefer receiving AdobeRGB, but other labs sometimes prefer, or require, sRGB or CMYK depending on their workflow.

If your images are highly saturated, wider gamut colour spaces on less capable monitors greatly increase your risk of creating something that cannot be replicated the way you intended. Knowing your monitor's limitations with your workflows gamut will ensure you can always output a "true" image.

What about XXXX Colour Space

Below is an image you may have seen a lot on the internet and but isn't explained fully in most places.

The faint curved colour underneath is limits of what the human eye can see, and each triangle is the gamut available to each of the labeled Colour Spaces.

By The original uploader was Cpesacreta at English Wikipedia - Transferred from en.wikipedia to Commons by aboalbiss., CC BY 2.5, Link

As you can see, sRGB is the smallest triangle, followed by AdobeRGB, followed by ProPhoto, but now your thinking "If ProPhoto has all that colour, why shouldn't I use it". To answer that I'll have to explain a little bit.

Each Colour Space does not have more or less colour based on its relative "size" to other spaces. The space is simply the definition of its most extreme colours.

In the Standard 8bit colour depth of photos, the "16.7million colours" is true regardless of which space you use. The higher you go in each colour channel however, the more different each space becomes. White is the same for all of them, but 255 red, 255 blue, and 255 green are all different in each space, with ProPhoto's 255 Blue being completely outside of human perception into Ultraviolet and as such impossible for computer screens to produce. Then depending on your output requirements, there is even more potential for ProPhoto colours to be "out of gamut" which most of the time, just results in a "muddy" colour when compared to the original.

What all this means is by working in ProPhoto you likely have no idea what colour you images truly are unless you keep everything relatively undersaturated as your monitor cannot display it at the extremes, and is altering the colours to keep everything within its output capabilities.

Apple Mac's preferred Monitor target in recent years is the DCI-P3 Space, which is Similar to AdobeRGB overall, however is more weighted to displaying reds over greens. So if you are using a Mac with a DCI-P3 Screen, then it is a good choice to have your files match this Colour Space to enjoy a more consistent "file to screen" match while editing.

CMYK is a type of colour space that should never be your "working" profile. While RGB Spaces have 16.7 million colours, CMYK only has 1 million. While the size of a CMYK colour space varies the same way as RGB ones do, the way colours are identified differs greatly. Where RGB is a value from 0-255 for each colour, CMYK is 0-100% of each colour. What you end up with is less choice in colour, and depending on the type of image, you may see every step in a colour gradient, so you lose  a lot of variation in your images.

Summary, What Should you choose?

Here at Art House our Art Copy Camera, Our Calibrated Screens, and our Canon Printers are capable of more than sRGB, and on some papers, more than AdobeRGB, but do not even come close to ProPhoto - they are however as good as it gets. That is why we request files to to be in the AdobeRGB Colour Space, because we can both see, and print them accurately within different papers gamuts. If you supply files to us in sRGB we will convert these files to AdobeRGB when we batch up files to print and there is no loss in colour accuracy doing this due to sRGB being "inside" AdobeRGB.

What profile you set your editing software to and subsequently what you embed into your files depends more on your equipment available than "what's best". Working with a good camera that produces RAW files is best and AdobeRGB should be part of your workflow for maximum accuracy on all screens. But an uncalibrated Wide Gamut Monitor is just as bad, or worse, than a cheaper sRGB only monitor as everything is displayed inaccurately.

Set your software to capabilities of the Equipment you have today and remember to change it when you upgrade in the future, or set everything to AdobeRGB and remember not to oversaturate files too much.

More on software setup, 8bit vs 16bit, which one is for you?