Why Use the ProPhoto RGB Color Space? (Podcast 423)

Why Use the ProPhoto RGB Color Space? (Podcast 423)

I’m often asked which color space to use in Photoshop, and when I tell people that it’s best to work in ProPhoto RGB, I hear various reasons why people don’t think it’s necessary. One of the main ones is the camera’s widest color space is Adobe RGB, but that of course is not true. Adobe RGB is available as a better alternative to sRGB for use in the JPEG previews in your RAW files, or if you should for some reason shoot in JPEG, that’s your lot.

Once you have your images in Lightroom though, it automatically uses ProPhoto RGB, you can’t even change it! When you go over to PhotoShop though, you have a choice, and far too many people select Adobe RGB or even sRGB, because that’s what your images are often exported in. Today I’m going to show you why that’s a mistake.

If you are already up on color spaces and just want to get blown away, skip down to the video below. If this is all going over your head a little, read on first…

Spectrum Locus with sRGB and AdobeRGB Color Spaces
Spectrum Locus with sRGB and AdobeRGB Color Spaces

What is a Color Space Anyway!?

Just in case you don’t know what I color space is, briefly, in this diagram you can see the Spectrum Locus, which represents all the colors that we can see. Computers work with large amounts of data much better though, if that data can be mapped out mathematically, so over the decades a number of clever people have created what are called color spaces, that basically map out colors based on straight lines forming a triangle within the Spectrum Locus. This enables us to give each color a number, that can be used to create that color on a computer.

As we see here, sRGB is actually quite a small segment of the visible spectrum, and although better, Adobe RGB is only in reality a bit larger that sRGB. To really show you the relationships between these color spaces and a bunch of others, in the video below I use a tool called ColorThink Pro to make it plainly obvious that ProPhoto RGB is the way to go when editing your images in Photoshop or any other image editing software.

Photoshop Color Settings Dialog
Photoshop Color Settings Dialog

ProPhoto RGB in PhotoShop

To set ProPhoto RGB as your working color space in Photoshop, just go to the Edit menu, and select Color Settings, and you’ll see this dialog box. Just select ProPhoto RGB as the RGB working space. Don’t worry about CMYK for now. You will usually only use that in pre-press work and when necessary, you’ll be told what color space to use.

I also turn on Ask When Opening and Ask When Pasting for Profile Mismatches and Missing Profiles too. This prevents me from using the wrong profile without realizing it. Really though, once you’ve made this change, you can pretty much forget that you are working in ProPhoto RGB, and just reap the benefits.

(Click on the screenshot to view larger.)

This goes for any other image editing software too of course. Whenever you can select ProPhoto RGB, it’s always best to do so, and save your working files in this color space, then use sRGB when exporing for Web or Adobe RGB when necessary, sometimes for printing services, and some stock sites prefer Adobe RGB, but that should only be selected when exporting your images for these purposes.

Editing in ProPhoto RGB from Lightroom

Lightroom Edit Image Dialog
Lightroom Edit Image Dialog

Note that if you send files from Lightroom 5 to Photoshop, there is no need to specify a color space as you leave Lightroom. When you do round-trip editing in other plugins though, such as Silver Efex Pro you will need to specify ProPhoto RGB as your color space, as you see in this screenshot (right).

As an aside, always select 16bit in the Bit Depth pulldown too. As a rule of thumb, to ensure that you never shoehorn your images into a smaller workspace, select the highest possible setting, unless it imposes unrealistic limitations on your workflow.

Some other plugins and applications, such as onOne software have their own color space setting. Surprisingly, onOne software is installed with Adobe RGB as the default, so you need to change this to ProPhoto RGB in the preferences before you start using the program. Once set though, it stays set, so the time investment in using ProPhoto RGB is minimal.

Not Throwing Color Away

It is worth noting of course, that you aren’t exactly throwing away color when you export to these smaller color spaces. The conversion takes into account the difference between the color spaces, and compresses and remaps the colors to fit into the smaller color space. You usually can’t see a difference on a computer display.

Wiggle Room and Future-Proofing

The major benefit of working in ProPhoto RGB is to maintain your full data for editing wiggle room, and printing, and we will also probably see wider and wider color spaces available in displays in the future too. Please don’t limit your images to today’s technology.

See for yourself!

Anyway, take a look at the video. I was giggling like a schoolgirl when I first looked at ProPhoto RGB in ColorThink Pro, and I hope this helps you to understand why working in ProPhoto RGB is really the only way to go. Don’t forget to go full-screen!

 Pixels 2 Pigment Aug 2014

Before you go, I just wanted to let you know that having just finished the first In-Studio Pixels 2 Pigment workshop, we’ve set the dates for the next one! It will be held on Aug 23-24, 2014, right here in my Tokyo studio. For details take a look at the Pixels 2 Pigment page. I hope to see you there!

Show Notes

ColorThink Pro: http://www.chromix.com/colorthink/pro/


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