Calibration of Reflective and Positive scanning

[MarkD]

I have an Epson2450 scanner and am using Win2K OS. I just received SF6.0 along with the calibration software and an IT8 reflective target.

I calibrated the reflective mode of my scanner and had the profile installed by showing "Calibration" in the "Scanner- Internal" box. I already had a positive IT8 target (slide) and calibrated the transparency/positive mode of my scanner.

1. Was the profile generated for the reflective scanning written over when I calibrated the scanner for the transparency/positive mode?

2. After I finished my reflective calibration and had it set in the "Scanner- Internal" box, I noticed on the "General" tab of "Options", Gamma was 1.8. After I finished the positive calibration, the Gamma was set to 2.0. Does the calibration compute these numbers or was I supposed to set them to match my monitor's gamma (which is 2.2 right now) ?

[ilyons]

1. Was the profile generated for the reflective scanning written over when I calibrated the scanner for the transparency/positive mode?

If it was a SilverFast created profile it will have been overwritten - if a third party profile it will still exist.

2. After I finished my reflective calibration and had it set in the "Scanner- Internal" box, I noticed on the "General" tab of "Options", Gamma was 1.8. After I finished the positive calibration, the Gamma was set to 2.0. Does the calibration compute these numbers or was I supposed to set them to match my monitor's gamma (which is 2.2 right now) ?

Typical values range from 1.8 to 2.0 for reflective and 2.0 to 2.2 for transparent. It is NOT essential to match the gamma gradation in SilverFast to your monitor. The values you mention are the defaults and generally work ok

[MarkD]

In reply to your answer to my Question No. 1, how do I keep both profiles in the system? If I can't, can the Silverfast profiles be saved so that the proper one can be plugged-in when I switch media? If not, it sounds like I have to profile my machine every time I switch media to scan. (It is my understanding that scanner lamps' light quality do not change fast enough to need profiling very often.)

[ilyons]

In reply to your answer to my Question No. 1, how do I keep both profiles in the system? If I can't, can the Silverfast profiles be saved so that the proper one can be plugged-in when I switch media? If not, it sounds like I have to profile my machine every time I switch media to scan. (It is my understanding that scanner lamps' light quality do not change fast enough to need profiling very often.)

You profile the scanner in reflective mode and it cretaes a profile with the R designation. You profile the scanner in transparent mode and creates a profile with the T designation. This means the profiles have different names - you didn't overwrite either and when you switch modes the appropriate profile is automatically selected. So long as SF Scanner Internal = Calibration it doesn't mean diddly what is shown in Scanner Reflective or Transparent.

See:

http://www.computer-darkroom.com/sf6-it8/sf6_1.htm

and

http://www.computer-darkroom.com/sf5-ne ... f5_cms.htm

[MarkD]

Thanks, having the profiles change automatically makes me a happy camper and I will read the tutorials. The tutoral on negafix, that you posted in your reply, will hopefully help me with scanning negatives as I had trouble with negatives when I used a bundled SE version of 5.5 a year or so ago.