Nope. I have a very old linear (scene referred) DCS image I use to illustrate that proper assignment is necessary in color managed workflows. Untagged, using the assumption in Photoshop (say Adobe RGB (1998)), it looks very dark. Assign the proper profile, it looks just fine, the numbers don't change a lick. Its not dark, it looks dark due to an improper TRC in the incorrect assigned profile. The profile I assign is a custom camera profile which of course provide "correct" tone due to its TRC and the image it is properly assigned to.
From this point, convert into another working space if so desired and use Perceptual assuming a V4 profile is available.
DigitalDog,
I would suggest that you re-read what I said. In my hypothetical example, I started out with an scene referred image that was properly tagged with its profile, in this case
linear_RIMM-RBG_V4.icc. If my color management is working properly, the image colors appear normal--it does not appear dark in a a color managed application such as Photoshop, but would appear dark with a non-color managed application. I want an output referred image with an sRGB tone curve and chromaticities and want to use perceptual rendering, since the original image did not fit into sRGB. If I
assign the profile
sRGB_v4_ICC_preference.icc, the image appears very dark since the numbers have not changed but a gamma of about 2.2 is assumed. To get an image that appears normal and functions as intended, it is necessary to
convert to the
sRGB_v4_ICC_preference.icc profile with perceptual rendering. The numbers change and the image then looks normal. The
ICC Paper Creating scene-referred images using Photoshop CS3 explains the process. See paragraph 11b in that document or do an experiment. I did the experiment and confirmed the above behavior.
In your case, you started with a scene referred image with no attached profile. Of course it didn't look right. If you assign the proper profile, it looks fine. The numbers do not change, but they are interpreted properly.
Bill.