Profiles and Color Workspace confusion

[jjones]

I am thoroughly confused. I can use the image editing power of PWP pretty well, and I think I can properly profile my equipment (scanner, monitor, printer, etc), but it's the actual usage of those profiles that has me all confused. I am asking for a bit of clarification.

I used Profile Mechanic Scanner and a nice IT8 target to properly profile my Epson V750-Pro scanner. I named that profile EPV750-R050302-300DPI-20090901.

Then I commenced to scan a couple dozen family photos. When I scanned the photos, I used the Epson Scan program that came with the scanner. I set Epson Scan's color-configuration according to the following screenshot:

Scanner Configuration for Scans

ScannerConfig.jpg (29.73 KiB) Viewed 5360 times

My confusion came about when I went into PWP to edit my images... I was trying to setup the Color Management dialog and I realized that since I didn't fully understand everything, I could not be sure I was handling the images properly. Here is my PWP (4.0.1.13) dialog:

PWP Color Management Settings

PWPSettings.jpg (43.87 KiB) Viewed 5359 times

My ultimate destination is for a Family Tree Website. Did I set this up correctly? Apparently not, because when I open an image for editing, I get the "Confirm Profile Conversion" dialog:

Confirm Conversion

Confirm.jpg (11.6 KiB) Viewed 5363 times

So I guess I'm just not getting it. It seems simple enough. Does "File Profile: None" in the conversion confirmation mean that the image-file does not have an embedded profile? If it does not have a profile, then where the heck did it go? Shouldn't the files have the EPV750-R050302-300DPI-20090901 profile embedded? Do the files have no profile and simply contain data that represents the sRGB color-space?

Can someone shed a little light on this for me please?
Thanks
Jeff

[jjones]

I'm sorry, this should probably be in the "Tips" forum. Please feel free to move it.
Jeff

[Dieter Mayr]

Hello Jeff

With what settings did you scan the target for profiling ?
You should have done with "No color correctiom" in the scanner driver.
And you should use the same setting then for scanning the images.
What you do now with your setting is double conversion.
You convert in the scanner driver from scnner profile to srgb and then you assume the scanner profile again to be the input profile in PWP.
I would set the scnner to "no color correction" and set the scanner profile as assumed file profile in PWP and let PWP do the comversion.
Assumed scanner profile is the assumed profile when using the twain function of PWP, but as it looks you scn in a file and open then in PWP, so the assumed file profile is relevant for your case.
As far i know the scanner driver (like cameras) does not embedd profiles.

Greetings from Salzburg

[elied]

I agree with Dieter. As it is set up now the driver is converting to sRGB and you are then telling PWP that it is really in the scanner space and asking it to convert again. Best choice is probably to turn off color correction in the driver and let PWP do it, but alternatively you can leave the driver as it is and tell PWP the assumed space is sRGB. Try it both ways to see if there is any difference.

[jjones]

Thank you. I think see now. Yes, I made the scanner's profile with the "No color correction" selected.

I did not know that scanners and cameras don't generally embed profiles. It makes so much more sense when I think about it in those terms. With your clear explanations, I can now see why there would be a double-conversion if I were to proceed in PWP with it configured as previously shown.

So, what you're saying is that the scanner driver used my profile to generate files to the sRGB space. In hindsight, that's not what I should have done, but I really don't want to rescan all the photos, and since I wanted them in sRGB space for the web anyways, I think I'll leave the scans as they are. My understanding is that the sRGB space may be a little limiting if my goal is to ever make prints.

I can also now immediately see why it would have offered the greatest flexibility-of-usage if I had scanned the photos with color-correction disabled in the Epson Scan program. From now on, I will always scan with "No color correction" selected in the program, and then use PWP to do all conversions as appropriate for final usage.

It also makes sense that I would do the same when making prints. That is, leave color-correction disabled in the print-driver and let PWP make all necessary conversions.

Leaving the scan-files as they are, here is my new, and I hope correct, PWP Color Management configuration. The change was that I set the Assumed File Profile to "EPSON sRGB" which is something that Epson installed when I installed the scanner, and I assume this is the "sRGB" that the Epson Scan program converted to when it generated the files:

NewPWPSettings.jpg (39.79 KiB) Viewed 5256 times

Your pointers were very illuminating. Thank you so much!
Jeff

[elied]

I think it is likely that the driver uses a generic profile for that scanner model rather than your profile that is specific to the individual device and since your home-made profile is probably better the 'conversion in PWP' option may provide a slight advantage.

As to the Epson sRGB, both Epson equipment and Canon software have deposited these icc files by me. I once compared
sRGB v.1.31 (Canon) and sRGB IEC61966-2.1 and found very tiny differences, mainly in the blue, IIRC. I don't know why they do that. Maybe to avoid paying royalties to H.P. who owns the official profile, but I don't really know.