assign vs. convert to profile

[David...@adobeforums.com]

Can someone please explain, laypersons' terms, the difference between these two options--I've been using PS for quite a few years and never really understood the difference. (Currenty using CS1)

Mosly, I want to assign/convert my camera images shot in Adobe RGB to an sRGB profile so that sharing and viewing them on the web will be more consistent.

Best, David.

[David...@adobeforums.com]

[Ho]

Then you want to Convert to Profile.

Visit the Color Management forum or use Google for a better explanation than I can give.

[Unknown]

Assign: the user "tells" PS what profile to use on a file. The RGB (or CMYK) numbers stay the same, but they are interpreted differently this usually results in a change in appearance on the screen. An RGB profile can only be assigned to an RGB file, a CMYK profile to a CMYK file

Convert: PS converts form one colour space to another. the RGB or CMYK number change. There is usually no or very little change in the appearance of the file (except for out of gammut colours). An RGB file may be convert to another RGB profile or to a CMYK profile

[Sid_Ph...@adobeforums.com]

You need to Convert. Also, I would convert copies and keep the originals in the AdobeRGB space.

[David...@adobeforums.com]

Sid and Ho, thanks; Convert it is.

Cyber Nomad, I don't fully understand your explaination of Assign; it makes me think its a temporary state, that you're only assigning a different profile for the time you're working on the file? Or???

[Paul_D._...@adobeforums.com]

David,

Here's the difference in a nutshell: Convert to Profile is used with "good" files, whereas Assign Profile is used with "bad" files.

Assign Profile is used to fix one of two problems:

(1) You opened an image that for whatever reason, has no color profile information in it. If you know what color profile should be associated with the image, you can use Assign Profile to fix this.

(2) You opened an image that has color profile information, but it has the *wrong* profile (there are several ways this can happen). If you know what profile the image should have, you can use Assign Profile to fix it.

Once you have a good file (that is, it has the correct color profile) you can use Convert to Profile to convert the image to a different color space. There are a number of reasons why you might want to do this, the one you mentioned (converting to sRGB for the web) is one of the most common.

[Daryl_P...@adobeforums.com]

David,

Assign: Tag an image file with the named color space, so that when a color-managed application reads that tag, it processes the image's colors as if they are within the gamut of that color space.

Convert: For an image with a tagged color space "A", transform the colors within that image to their nearest counterpart that is within the gamut of color space "B" and then update the image tag to indicate it is now in color space "B".

So, let's say you are provided with an image file that someone has stripped out the EXIF data from that normally provides the color space information, but they tell you the image was shot with a digital camera which was configured to use the AdobeRGB color space. Now, you want to edit that image in Photoshop but you have set up PS with a color workspace of "BestEverRGB". Knowing what you do, when you open the file and Photoshop asks if you want to assign a color space, you select "yes" and assign it as AdobeRGB. Then, since Photoshop knows the gamuts for AdobeRGB and BestEverRGB, it will perform a transform of the image colors so they are represented correctly to you in your workspace.

Now, let's say you finish your edits and save your file. At that time, it will be saved with the BestEverRGB profile. But, if you view that image in a web browser that doesn't use the color profile data, you find that the colors are shifted from what you expected. What to do? Well, devices and applications that don't use color profiles or which aren't color managed are often designed around the assumption of an sRGB color space. So, what you want to do is convert your image to the sRGB profile so that PS will transform the colors from how they are represented in BestEverRGB to the sRGB gamut. Then, whether saved (normal Save or Save As) or without (Save for Web) the sRGB color space tagged to the image, it should appear more as you'd expect to see it, when viewed in applications that don't use said information.

Meanwhile, if it happens that you liked BestEverRGB because it works so well for your SuperDuperInkjet and produces great color detail, you can always use the image you edited before you converted it to sRGB. :)

Hope that makes sense,

Daryl

[Daryl_P...@adobeforums.com]

Oops...I missed this duplicate thread and posted my reply in the first, if a moderator could merge them or perhaps even delete the other, since my reply doesn't add much beyond what has been said here already.

Thanks,

Daryl

[David...@adobeforums.com]

Paul, Daryl, et al, thanks for response. I'm still a bit fuzzy on this, but I gather that Convert is what I want to use, and yes, I am doing this on a duplicate that I'm creating in Save for Web. I always save the "original" as a .psd file and don't change the Adobe RGB profile (or is it a color space, gosh I don't know?).

And in laypersons' terms, here's what I've gleaned: I am an image file wandering around with amnesia, and I don't remember my name/profile, so someone "assigns" one to me, David Doe. A bit later I find that when I share my name on the web, not everyone can pronounce it, so I "convert" it to David sRGB. Or some such rot.

Best, David.

[Timo_...@adobeforums.com]

Hello

At this time i used CS2
I惴 waiting for my new Version of Cs3 by mail-order. Up to then i扉e installed the trial to try out the 3d-Functions but the Import of 3ds-files fails. After clicking on the 3ds-file at the Openmenue i get an sreenshot of my desktop in my working-area? I惴 perplex at this result. Is this because its a trial? I can愒 believe this.

Thanks

[Chuc...@adobeforums.com]

Tried that (600x600) and it dosen't work for me. Besides if you are doing detailed textures for 3-D 600x600 is not going to give you very detailed results.

[Eric_...@adobeforums.com]

The problem has went away. Here is the fix.

When I first imported a 3DS model into PS I got a window asking me the window size and for the first week I accepted the default size and got a screen shot of my desktop.

How the fix came about is that I changes the default size to 600x600 and then everything worked out great.

Seems like a way to easy fix but ever since I tried that every model now imports fine.

[Eric_...@adobeforums.com]

Your right the 600x600 will not generate very details results. My point is that after I changed the default values to something different than the default I was able to import my 3ds model in at any size.

Chuck Ray, are you getting the same screen shot of your desktop problem or something different?