Let me preface this by saying I am not 100% up to speed on how color works in QXP8, which left R&Ds hands a long time ago, but of course I know the way it works today, and so I should think what I am about to spout is close.I understand this is a Dark Arts, subject, but I am struggling to come up with a more straightforward answer.The answer I give here is somewhat simplified because there are some edge twists and turns that just make things more complicated than they need be, so I am going to skip those codicils unless someone insists otherwise.First, some explanationsthe data for a bitmap image, always has a "colourspace".There are lots and lots of colourspaces, but only two that need concern us here, DeviceCMYK, and ICCProfileBased(CMYK).Then, there are devices. monitors, printers, scanners, cameras, etc. We are interested here in the input device (let's say it is a camera), and the output device (printer).DeviceCMYK says that the image data is already in the colourspace of the output device.ICCProfileBased says the image data is in the colourspace of a different device, most likely the input device, and must be converted to the output device space.QXP writes the final PostScript data in DeviceCMYK space: so the contract is, that all the data PostScript sees, is already converted to output space.The description of that output device you can control in the output setup dialogs. Let's say, you want your target device to be a sheet fed Heidelberg device printing on X gram substrate (paper). You have the ICCProfile for that set up. You set that in the output set up as the device all your work is going to.So now the idea is that all pictures, text, lines, paths etc, should either be supplied directly in colour descriptions in that output set up, OR a mechanism is given to PostScript to do the conversion. If there is a mismatch of colourspaces, there will always be a conversion at some point in the pipeline: either QXP will take care of it, or PostScript will do it.If your images have no profile, then the contract says, that they output in DeviceCMYK. i.e. for good or bad no conversion takes place in output.However, if your images have an embedded profile, or you have assigned a profile to them via the input set up, then the contract says, a conversion must take place to get the data into the output device space, (unless the images have exactly the same profile as the output space). If you have told Photoshop to embed the Sheetfed Heidelberg profile, then, I would expect your image would be sent straight to PostScript as DeviceCMYK, because the input and the output colourspaces match. Only if the images advertise themselves in a different colourspace, must some conversion take place.For screen, a conversion MUST ALWAYS take place, because the screen is RGB. QXP will always use the profile that describes your screen monitor to do that conversion. Problems occur either when users have assigned the wrong profiles to the source images, or the wrong profile to the monitor. Easy enough to do.Finally, back to who does the conversions, if they must take place.Normally QXP does the conversion, because it wants to write out DeviceCMYK.However, you can ask QXP to hand off this job to PostScript. What happens there is that the entire ICCProfile is embedded in the PostScript output, This is called a CIE, and you make that happen by creating an Output Setup that is AsIs with the color management box checked.Personally, I don't see the point in this, for technical reasons that I won't bore you with. Nevertheless, the option is there.I can expand on all this further if you want.