Scanning film problem (dynamic range)

[ishpop]

I am using an epson 4490, and often find that the color scans, usually slides, come out strange. Below is some velvia that exhibits the problem well:

Notice the blotchy blue in the center?

I can move the sliders in certain directions and somewhat control this, but it then either over or underexposes the shot in a way that is not at all representative of what I see when I look at it on a light box, where it looks great.

 

[ishpop]

Also, sorry for wrong forum, meant to put this in scanners

 

[mfogiel]

Are you scanning in 48 bit?

 

[ishpop]

Are you scanning in 48 bit?

Yeah I think so. 1200 dpi, 48 bit.

Should I change either?

 

[mfogiel]

If you are scanning in 48 bit, and you set your histogram extreme points correctly, then the problem could only be the scanner itself.