Scanning issue -- KM scan Elite 5400 II - shadows

[Let Biogons be Biogons]

I'm using a Konica Minolta Scan Elite 5400 II with Vuescan software.  Haven't used this in a long time, but it's not THAT complicated and I've never had this issue before, so I'm wondering if someone can tell me what might be the problem.

Scanning some old 35mm slides.  Viewed on light table they look fine.  Scanner using the 5400 II I'm getting what looks like posterization in the shadows.  See the attached file.  Any suggestions as how to correct this, or avoid this?  What am I missing, what have I forgot?  Thanks!

[TonyW]

No experience with the Minolta and Vuescan but two+ possibilities come to mind looking at the image

1.  Not scanning at an adequate bit depth.  Ideally should be looking at scanning 48 bit (16 bit per channel)
2.  Pushing too hard in post to bring image to an acceptable level
3.  Combination of both the above

[Let Biogons be Biogons]

Thanks.  Was scanning at 48 bit depth.  No post processing on the scanned file at all. 

[Bart_van_der_Wolf]

Scanning some old 35mm slides.

Which type of slide film? If Kodachrome, make sure to disable IR dust removal.

Cheers,
Bart

[Let Biogons be Biogons]

Damn good question.  I don't know.  35 year old slides processed by non-Kodak lab.  I suspect they are Ektachrome/E6 but don't know.  I'll try disabling IR noise reduction.  I mounted them in a consumer Epson flatbed (V330 Photo) and used dust removal feature in Epson Scan, and it seemed to work fine.

[degrub]

the V330 is likely the issue. not enough dynamic range, Try a slide scanner or do two passes, one for high key and one for low key.

[Let Biogons be Biogons]

Actually, the V330 Photo w/ Epson Scan did fine.  It was the Konica Minolta Scan Elite 5400 II dedicated film scanner that had the problem.  I tried the V330 after I had the issue (shown in the image in the first post) with the KN 5400 II.