Colour Space - A Clearer Understanding

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Colour Space | nickdjeremiah.com
 

Please take note: If you use a wide gamut monitor, produce fine art inkjet prints or are a commercial photographer, this article likely doesn't apply to you.

Colour space is a complicated subject, and for a lot of photographers is something they don't know anything about. I'll start off by explaining some terminology and a visual representation of colour before getting into the nitty-gritty details.

  • For the majority of you photographers out there, you're better off working in a full sRGB workflow. I explain why later in this post.

  • If you're using a wide-gamut monitor, you need to be working in a full Adobe RGB (1998) workflow.


Overview

Terms

Gamut - A gamut is the range of colours that a device can capture or show.

Colour Space - A colour space is a predefined specification that defines a particular group of colours. A colour space is mapped into a device’s gamut so the device’s colours correspond to the real-world.

Colour Spaces

CIELAB - LAB is the colour space that closely resembles the colour gamut of our eyesight. There's a lot more to it than that, but this is pretty much all you need to know about it.

sRGB - In 1996, the sRGB colour space was developed as a standard for display technologies. The majority of consumer monitors and displays output this colour space. It stands for Standard RGB (red, green and blue).

Adobe RGB (1998) - For artists, Adobe created the Adobe RGB standard in 1998. While the blues and reds are identical to sRGB, this colour space accommodates more vibrant greens. If artists do their work in Adobe RGB, they must use professional wide-gamut displays to accurately view their work.

DCI-P3 - DCI-P3 refers to the colour space used in digital movie theatres and encompasses much more than sRGB. Hollywood films are provided to theatres in DCI-P3 in order to match the gamut of the digital projection equipment used.

ProPhoto RGB - This is the largest colour space available. It is so large in fact that the majority of the colour is known as 'Theoretical' because they fall outside the gamut of a human's vision. Or in other words, they don't exist. You do not want to use this colour space. More about ProPhoto RGB later in this article.

File Formats

RAW: A file format that is essentially the digital equivalent to a negative. RAW files don't take on any colour space data.

JPG: A file format that you could argue is the equivalent of a polaroid. Once you take the image, you can't do a real lot to it. JPGs store colour space data.


Visual Representations

Let's take a look at a visual representation of colour space. Most consumer displays can only output sRGB. Apple's iMac and MacBook Pro's output the DCI-P3 colour space, and the professional wide gamut monitors made by Eizo and NEC output Adobe RGB (1998).

On the left, is a representation of the Adobe RGB colour space. Next to it you will see the DCI-P3 colour space. The white outline shows where Adobe RGB is in comparison. You can see that P3 is not quite wide-gamut but it's pretty close. It's actually 25% larger than sRGB.

Below, on the left, you can see the Adobe RGB colour space. This is the colour space that commercial and most professional photographers should be working in. On the right, you can see the sRGB colour space. The white outline shows the comparison between the two. sRGB is what all consumer computer monitors can display and what 90% of photographers should be using. If you're an event photographer, into family portraiture or newborns for example, there's no need to use a wider gamut as your clientele likely doesn't require it. Not to mention the need for an expensive wide-gamut monitor.

Please Note: C-Type prints are sRGB. If you're getting Giclee (or Inkjet) prints done, they should be in Adobe RGB but some labs don't do it. So consult your printer before hand.


The Nitty-Gritty

So why should I be working in the sRGB colour space?

For the majority of us, we aren’t editing on a professional monitor, one that can display the Adobe RGB (1998) colour space. These monitors are known as wide-gamut. Most of us are working on laptops, iMacs or standard monitors, all of which can only display the sRGB colour space. When editing, you only see a sRGB version of your image because the monitor you are using can only display that colour space, and therefore you are making adjustments based on a sRGB rendering. If you were then to save and print that image in Adobe RGB, your prints wouldn't look like your image on the screen. You'll likely see more colours, and they have the potential to be oversaturated.

The reason for this is because Photoshop's (or your preferred photo editor) working colour space may be set to Adobe RGB. When making adjustments to your images, all these changes are happening in a larger colour gamut than what your display can produce. So when you increase the saturation of the blues, for example, they're being saturated more than what your display can show you.

If you shoot RAW, this is less of a problem. RAW images have no colour space and are assigned one once it is in the editor. So even though you’re working in a smaller colour gamut (sRGB), you’re not doing any harm to the image. If you do need that larger colour space, you’ve still got it because you shot in RAW. Just change the colour settings in your editor to Adobe RGB and re-edit the colours in your image. If you’re working in Adobe RGB and convert to sRGB, then print in sRGB, your prints will look the same. However, if you’re going to convert the colour space, you should work natively with it from the beginning. It'll save you time, your colours should typically look nicer, and you'll reduce your chances of colour banding (this can happen when colours are converted and squished into a smaller gamut).

If your non-commercial client asks for an Adobe RGB image, it would be better to educate them on this matter. Unless they can reproduce that colour space, then they probably don't know what they're asking. If your client is professional or commercial, however, they'll need Adobe RGB. In this case, it'll be worth the investment to upgrade to a wide-gamut monitor. You don't want to risk providing them with an image with wacky colours.

The only way to get an almost exact match with colour is if you’re editing in the same colour space as your monitor can display, and you're printing in the same colour space as you were working. Not to mention, web browsers can’t display Adobe RGB even if you’re using a wide-gamut monitor, so when you upload images to the web, they must be in sRGB regardless of what monitor you’re using. Otherwise, your images look muddy and the colour desaturated.

Always work in the largest colour space available
— every pro photographer ever

Many pros tell you this, and they're right. However, you can’t always see the largest colour space, so the edit you’re making can look very different. The in-gamut colours should look the same, but the out-of-gamut colours won’t. If you don’t know what they look like until you print, it's not a risk you want to take as it costs time and money. However, what about soft proofing? Isn't that for this exact issue? Well, no. Soft proofing cannot show you out-of-gamut colours if you’re monitor can’t. Soft proofing is for seeing what your image will look like printed on a particular paper from a specific printer; it cannot show you what it looks like in a larger colour space. It can show you where the colours are clipping (going out-of-gamut) and this gives you the ability to edit further to fix those issues.

A native sRGB image tends to look better then an image converted to sRGB. So it’s best to work in the final output colour space from the beginning to get the best quality image, but only if you can see it.

I am a commercial (or) wedding photographer. Should I be using Adobe RGB?

Yes, you should. Commercial photographers are working for commercial clients. So their images are likely displayed in magazines, billboards, posters and many other mediums that use the Adobe RGB colour space. So you must be working in an Adobe RGB workflow from camera to print. If you're a wedding photographer, you should be getting fine art prints done at a pro lab, printing in Adobe RGB because the images look 100 times better (please consult your printer about what colour space they print in before sending them images). If you're providing any client with digital files, however, they'll need to be in the sRGB colour space because they'll only be able to view it that way.

Investing in a wide-gamut monitor is an essential task and something you should start saving for. I have linked two affordable ones below for you to check out.

BenQ SW2700PT | nickdjeremiah.com

BENQ SW2700PT 27" MONITOR

This monitor is serious bang for your buck. 27 inches on the diagonal, Adobe RGB 1998 wide-gamut colour, IPS panel, 10-Bit display, hardware calibration and much more. Click the Learn More button below to... well, learn more.

— $599 US
— $790 AUD

Eizo_Monitor.jpg

EIZO CS2420 24" MONITOR

This is Eizo' entry level wide-gamut professional monitor. If you're just getting started with the Adobe RGB colour space and want to make fine art prints, this is the best monitor to buy.

— $860 US
— $1200 AUD


The ProPhoto RGB Myth

Visible Colour Spectrum | nickdjeremiah.com

You may of heard of the ProPhoto RGB colour space, and you may of heard a lot of 'professional' photographers touting that you should be using it because it's "the largest colour space and you should be working with all the colours". This is total rubbish! The ProPhoto RGB colour space encompasses such a large colour gamut that it actually falls out of the visible colour spectrum of our eyes. Those colours are known as theoretical colours because we can't see them but we assume that's what they look like. Photography is all about seeing, and making sure your images are colour accurate is extremely vital. So why would we use a colour space that includes colours we can't see? Exactly... We wouldn't. And you shouldn't.

But that's not the only reason. There are colours in ProPhoto that we can see, and these colours are far and above the gamut of Adobe RGB. However, there isn't a monitor or printer available that can print above the Adobe RGB gamut. Even though we can see part of ProPhoto, we can't reproduce it, which leads me to ask, why would we use a colour space we can't reproduce? Exactly... We wouldn't. And you shouldn't.

To the right is a graph. It is showing five colour gamuts. LAB (the horseshoe shape), ProPhoto RGB, Adobe RGB, sRGB and CMYK. LAB is approximately the gamut of the human eye. You can see that ProPhoto's triangle goes beyond LAB in the greens and the magentas. These colours don't exist. Or at least we can't see them and never will, so they might as well not exist.

With all that said and done. Don't use ProPhoto RGB. You can't see it, you can't reproduce it, so why would you use it.


 

I hope this article has been an interesting and informing read. If you have any questions or comments to make, comment below. Also, if you’d like to receive an email every time I publish a new post, you can subscribe to my mailing list below.

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