CoolScan 9000: How to eliminate banding in the shadows?

[hassiman]

When I look at scans of some dense kodachrome I see faint banding in the shadow areas. :(

Is there a setting to use in AI Studio that will eliminate thsi problem?

[degrub]

Depends on what the source is.

Have you looked at the film with a 10x loupe on a light table ?

Could be some dirt/dust on the mirrors.

Try a multi sample - 4x should be good enough to see if it is sensor noise.

i forget which way got around it in the 8000, extra fine mode ( all rows of the sensor) or normal (single row) - but i think it was usually in the lightest areas of the slide, not the darkest, so i think it was single sensor row version. IIRC, there was a mechanical resonance with the faster motion of the sensor.


Could be voltage ripple coming to the sensor. Do you have a good (transformer based - not the IC synthesized AC) surge protector/UPS in front of the scanner ? At least a good A/V spec filter should cut out any significant AC noise. Won't address any voltage droop or correct the sine wave though.

You may also be able to eliminate it by adjusting the lower end of the channel curves to exclude the bottom end of the signal. Look at each channel and see if one is carrying the banding or if all are . Adjust if you can without introducing a cast.

[hassiman]

Dear Degrub,

The banding shows up when I bring the shadows up it appears. I had heard that it is the single line of sensors that will get ris of the banding... but I am not even sure if I have AI Studio set up correctly for the 9000.

I am still trying to get the profiling steps to match the instructions... I am not sure about the settings I should have on the options pages for regular and HDR scanning. Any chance you could send me screen shots of your options pages?

I am scanning 35mm K-25 and B&W and 6X6 Velvia and B&W.

I hope I can get the hang of this soon... getting frustrated.

[degrub]

THis is where i learned...

http://www.computer-darkroom.com/sf5_contents.htm

#1 and #6 should get you there.

[LSI_Rossee]

When I look at scans of some dense kodachrome I see faint banding in the shadow areas. :(

Is there a setting to use in AI Studio that will eliminate thsi problem?

Dear hassiman,

you definitely want to make sure you are using extra fine mode. From my memory it would be under Options -> Special in SilverFast for the Nikon 9000.

Best,

JAN

[hassiman]

Dear degrub,

The problem I am having is the I prview the iT8 slide... I crop it as instructed, I click on profile, the smallll IT8 box appears on the left and the profiling starts before I click on START and then it says the profiling has completed... but the IIC profile SAVE box never comes up as shown in PDF #1 :o

[LSI_Rossee]

Dear hassiman,

SilverFast will store the ICC-Profile where the system will look for it by default automatically. It will automatically set the just created ICC profile as input profile for the scanner in the CMS settings of SilverFast.
However there is a way to make the Save dialogue come up. Go to Options --> Automatic --> tick "Custom profile name".

Greetings, JAN.