Avoiding Auto Corrections in Silverfast Ai

[Felix]

Although I have studied the Silverfast manual I am still uncertain about the role of the Auto panel in the General Section of the Ai settings. That is, I do not understand whether the settings activate only when Automatic corrections are applied, or whether they play a general role in setting parameters for the data scanned.

At present, my general aim is to deliver as much data as possible into Photoshop, as unedited as is consistent with color managment, within the limitations of my equipment and the stock profiles. I am endeavoring to achieve an understanding of how the software operates on the data the scanner delivers before I venture into custom profiling.

I am scanning 48-bit color (auto-sharpening off) into Photoshop from an Epson 2450 (now speaking of reflective scans). The Gamma in the General Panel?General Options of Ai is set at 2.20, perhaps wrongly, to match the 2.20 gamma setting for the Photoshop default RGB color space, Adobe RGB 1998, as well as the 2.20 for the Apple iMac 17" LCD display via ColorSync calibration.

General Options:

Colormodel?RGB; Default?Silverfast DeFaults (only choice); Interpolation?Antialiased; Gamma-Gradation? 2.20; Q-factor 1.0 (I don't yet really understand what Q-factor is, despite the description in the Silverfast manual.)

In the CMS Options Panel I have:

Color Management
Scanner?internal ColorSync; Internal?Monitor Automatic; Internal?Output RGB

Profiles for ColorSync
Scanner (Reflective)?Epson Perfection 2450; Internal?Adobe RGB 1998.icc; Gray-Generic profile,icc; Output-Printer?None; Rendering Intent?Perceptual

Embedded ICC Profiles
Embed Profile?Checked for Adobe RGB 1998

Special
Halftoning?No Dither; Color Filter White; Limit Gamma Slope?Unchecked.

Finally, reaching the Auto Panel, the settings now are: Auto Threshold highlight?2; Auto Threshold Shadow?0; Highlight Offset?3; Shadow Offset?98; Color Cast Removal?0; Auto Frame Inset?0; AutoPip Middle Factor?a tipsy elipse;
Auto Contrast?Unchecked; MidPip Fixed Target?50 with Active box Unchecked.

I have been struggling with the settings for some time and would truly appreciate some help with understanding where and how I am effecting necessary versus unnecessary limitations on the data being scanned.

Felix

[LSI_Kratzenstein]

The autosetting are only used, when you use the Automatic button.
the settings are correct, to get as much data as possible unchanged from the scanner. Just HDR mode give more exact data, but the only difference is, that this don't use the scannerprofile and don't use the gamma setting (per default).
Teh Q-factor is the quality factor, important for the press, there it should be 1.5.

Kratzenstein

[Felix]

Thanks very much for your reply, Kratzenstein. I had been afraid that in fooling around with the settings I had introduced some limitations in tonal range of which I was unaware.

Felix