48 bit color scans for Epson V-750 broken? Support silent

[drounds]

The 48bit color setting on my Epson V-750 is producing very dark scans. It's been almost a week since I last heard from from SF support but have heard nothing since. Perhaps other users of SF for the Epson V-750 are experiencing the same problem with 48 bit color scans (NOT HDR). Here are the steps I took to reproduce the problem for a 35mm slide:
1.) perform a clean prescan
2.) load saved settings
3.) add a image with 48->24 colour selected to the job manager
4.) add the same image again to the job manager
5.) edit the scan type setting on the second entry in the job manager, changing it to 48 bit color.

The icon displayed in the job manager immediately darkens. When the job is completed the resulting 48bit image is much darker than the 24 bit image of the same slide. The file sizes confirm that the darker image contains 48 bit data. In PhotoShop the 48 bit image also appears much darker. These are the histogram reports from within PhotoShop:

Scan Type::24 bit::::48 bit
Mean::::::::119.17:::25.89
Std Dev:::::50.14::::16.91
Median::::::118:::::::21
Pixels:::::::104272:::104272

For what it's worth Epson Scan produces acceptable 48 bit scans using this scanner. Any ideas ?

[degrub]

Does that happen when you do not use job manager ? and select the settings manually ?

[drounds]

Yes, I just imported a scan into PhotoShop Elements 4.0 with the same results.

[degrub]

are you using "auto adjust" or setting the white and black point manually ?

[drounds]

I'm using auto adjust. I've been testing with a carrier full of slides. I'll try setting the points manually.
Thanks

[drounds]

Same results setting the white and black point manually. Has anyone with a V-750 scanner made any 48 bit color scans? I could believe that there is some setting I forgot. Even so that seems unlikely when I get great scans only changing the mode setting from 48bit color to 48->24 bit.