Getting very odd colors when converting profiles

I am having the same problem! 

BTW I very much appreciate your time..

Yes. If it says "untagged", don't convert. Find the right profile and assign that first.

The problem, of course, is that you don't know what the right profile is. Sometimes you can make a good educated guess simply based on what looks good and "natural", but basically you have no way to know for certain. So then you need to go back and ask.

With your unicorn, the left version looks best. The purple sky on the right can't be intended. But also - those purples are very typical of a ProPhoto image displayed in one of the smaller color spaces like Adobe RGB or sRGB. So that kind of looked like a smoking gun to me.

So if I turn off all warning and it does NOT have a profile embedded, it will say "untagged" correct? And if so you are advising I do NOT convert it to any profile at all prior to printing? For what its worth I don't use Photoshop to print only for image adjustments. 

This whole thing boils down to a valid profile being embedded. Whether the profile is bad or missing amounts to the same thing: all bets are off and you don't know what it's supposed to look like. It can have too much or too little saturation depending - you just don't know.

I'd recommend to just turn off all the warning dialogs. Trust what it says in the status bar.

The same thing happened with a few images last week from a different customer. Those were not scans but sRGB files created in Photoshop, but I don't think they embedded the profile when exporting. In this case, the unsaturated image was accurate as told by the customer. Same thing with the images last week the saturation was somehow jacked to 1,000. But Apple Preview isnt doing this when I open it there, so those have been my references in both cases. When I converted this untagged horse image to sRGB it looked better, and more how the customer wanted. 

I guess I'm also confused because I was under the impression that files converted "up" would look the same. So if I got an image from LR where I store my own photos, and converted it from Pro Photo in LR to Adobe RGB in PS, then BACK to Pro Photo in PS (just for testing purposes) the photo would remain the same. That basically the gamut could not be expanded as the data was lost when I converted it down to Adobe. 

I feel like for now my practice should be converting to sRGB when im sent an untagged image as thats most likely what my customers are used to. People who are more advanced and work with thier own photos or art generally send me files with embedded profiles and this isnt an issue. 

This is how a ProPhoto RGB image looks if you assign Adobe RGB or Display P3 which is very similar.

What I think happened here is that the scanner profiles are non-standard and get thrown out in other applications because they're not written to correct icc spec. That's not uncommon.

I suspect the left (saturated) version is the correct one, but you should go back and confirm that. Ask them to resave the file with a good standard profile embedded (not a scanner profile).

So I tried turning off the auto convert profile. I opened the file and was still prompted with a message saying its embedded profile is different than my working space. I chose to keep it with its embedded profile. The prompt said that was sRGB. However when the file opened, its marked as "untagged RGB" in the lower left. The image still looks WAY off. Im enclosing a screenshot of the image in PS next to the same image in Apple Preview. The Apple Preview version (right) is how its supposed to look. This happened with all three files from this customer, all scans from different scanners. 

@phototocanvaspdx 

But the question was, is there an embedded profile? If not, it may be wrong whatever you choose.

That's why the status bar setting that I showed is much more effective than any of the warning dialogs. You spot untagged files right away and can decide what profile seems to fit best.

I have it set to prompt me and no matter what selection I choose to use the embedded profile, to convert, whatever I do it's still screws the colors up.