The colour and tonal information in a digital document is stored as numbers. When we share these documents between devices, the device has to work out how to display the colour. As not all devices can display the same colour gamut it can lead to colours looking different on each device.
To ensure that the colour looks the same on each device, we use colour profiles to tell the device how to display or render the colour information.
In Affinity Designer, an opened file's colour profile is honoured by default. You have the option to convert it to the current working colour space. When placing images into an existing document, the image's embedded colour profile will always be converted to the document's current working space.
On export, you can choose to embed the document's or a named colour profile to ensure accurate colour management. Alternatively, the exported file can be unprofiled by not embedding the document or named profile.
Assigning colour profiles
Affinity Designer lets you choose global default colour profiles, assign a colour profile as you create a document, or at any point during your session.
To select default global colour profiles:
From Affinity Designer>Preferences (Colour option), select an RGB, CMYK, Greyscale or LAB colour profile from the pop-up menus.
Choose a Rendering intent option and check Black Point compensation.
To select a new document's colour profile:
As you create a new document, select an option from the Colour Profile pop-up menu.
To convert the colour space of file to be opened to the current working space:
Prior to opening the file, from Affinity Designer>Preferences (Colour option), check the Convert opened files to working space option.
Prior to opening the file, from Edit>Preferences (Colour option), check the Convert opened files to working space option.
Options exist to warn that a file's working space will be converted, or that an unprofiled file will be assigned the current working space's profile.
To change your document's colour profile at any time:
From the File menu, select Document Setup.
From the dialog:
Select the Colour tab.
From the Colour Profile pop-up menu, select a profile.
Select Assign or Convert. Assign adopts the new profile but leaves the values of the colours/pixels as is. Convert converts each colour from the old profile to the new one—colour/pixel values may change as a result.
To embed a colour profile on file export:
With Export Persona active, choose your Preset in the Export Options panel.
(Optional) Select a different ICC profile from the pop-up menu. Otherwise, the document's colour profile will be embedded.
Check Embed ICC profile.
About soft proofing
Soft proofing simulates output as you design with respect to the colour profile and the paper medium you intend to print on.
In Affinity Designer, this can be done by applying a Soft Proof adjustment to your design. You can then preview how your output will appear, preventing any nasty surprises at print time.
Because soft proofing is applied as an adjustment you can apply multiple adjustments, and therefore produce soft proofs for multiple output devices.
As an example, if you want to create several different output types, you might want to start with a colour profile on document creation with a wide gamut (e.g., Adobe RGB 1998), and then change the profile to match the output destination. However, colour information may be thrown away if changing to a smaller colour gamut—simply changing back to a profile with a wider gamut will not restore the additional colour information. By applying a soft proof adjustment you prevent this, allowing you to work in a wider gamut until you are ready to change to your chosen output profile.