Which Profile to Assign to photos ?

Question

Good day all.
I have been re-checking all of the photos in my hardcover book to make sure they will print well.
Of course now I am more confused than ever.
In Preview > Tools when I click on the "Assign Profile" I am even more confused.
Firstly, each photo I open , the info says Color Model is RGB (I assume this is what I want it to say), but next to Profile Name, some photos say Camera RGB Profile, yet others say IMac, and yet others say "nothing".
My choices of what to assign to each photo are as follows:
Adobe RGB (1998), Epson Adobe RGB (1998), Epson Apple RGB, Epson Color Match RGB, Epson sRGB,
Generic RGB Profile, IMac, sRGB Profile
Most of my photos are color but have about 20 that are black and white, but have been assigned RGB. There are a few photos that come up "Color Sync Profile" with either IMac beside them or nothing at all.
Could anyone please advise me as to which of these profiles I should assign to my photos.
The more I read the more lost I get. I hope this plea for help isn't too confusing.
Thanks
PJC

Answer 1

What you want is either the Camera RGB Profile or the sRGB Profile – they are almost identical.
Do not under any circumstances use "Assign Profile..." on any images that have a profile different from the two above assigned to them. That would distort the colours.
Instead you need to convert them to the Camera RGB- or sRGB Profile. If you use Preview as your editor choose "Match to Profile..." and select either profile.
It's hard to say what to do about the images that lack profile information. They might have originated in the sRGB colour space so again they should look fine with either the Camera RGB Profile or the sRGB Profile. In this case it is helpful to use the Assign command instead – if they look good afterwards save them, if they don't, try another profile until you like what you see and afterwards convert them as described before using *Match to Profile...*
The reason I recommend this is that the iPhoto printing service seems to be geared towards sRGB. Many users have reported unsatisfactory results with images that had another profile such as Adobe RGB (1998) assigned to them.
For more background information read Assign versus Convert – in Preview convert is called *Match to Profile*.