Robert D Feinman

Minolta 5400 Scanner "streaks"

There have been some concerns that scanning software used with the Minolta 5400 can produce streaks in the finished scan.
Some users favor one brand of scan software over the others. I have found that Vuescan has had the best balance between quality of the final scan and speed of processing. Others have been unhappy and there have been continuing releases to improve the problem.
The picture at left is a scan of an opaque piece of cardboard treated as a positive transparency. It should reproduce as pure black.

  Emphasized Opaque Image
This was scanned with Vuescan 8.1.12 with no imaging correction and appears completely black under normal viewing conditions.
To highlight what some users may be troubled by the curve at left was applied to the above image.
As can be seen this curve maps any values above 21 to maximum black. All the actual values actually fall below this value so the effect is to greatly emphasize the inherent noise in the scanner.
black curve
Emphasis Curve
This is the same sample with the grain dissolver applied. Since the subject is opaque and the grain dissolver is on the lamp side of the carrier the fact that there are differences between the two images seems to imply that there is some processing being done by the scanner in software when the grain dissolver is applied.
I don't have an explanation for the streak.
opaque with grain dissolver
With Grain Dissolver
This is the same image with IR cleaning (light setting) added. Since the IR channel should be blank it appears that the cleaning post processing gets confused under these extreme conditions.
with cleaning
With Grain Dissolver and IR Cleaning
This example shows a similar area using the Minolta scanning software. The exposure adjustment was set to auto and a curve similar to the above was added during the scan. The results seem similar to Vuescan.
minolta scan auto
Minolta Scan With Auto Exposure
Here is the same scan as above with the combined ICE and grain dissolver added. It would appear that the software also has cleaning problems under these conditions.

Minolta with ICE
Minolta Scan with ICE Added
This is a scan of a blank frame with an emphasized curve applied using Vuescan. blank scan
Vuescan of Blank Frame
Here is the curve applied to the above image to emphasize the small variations in density. In this case any values below 249 are set to 0. white curve
Emphasis Curve for Above Image
He is the same scan as above with the grain dissolver added. In this case there should be some difference since the light source is not modified.

There are no samples for the similar case with the Minolta software since I was not able to get it to generate a scan that had any values other than 255 under these conditions.

Once again it should be remarked that all these examples are artificial since no real piece of film will ever be totally opaque or transparent. In addition viewing these scans without the applied curves shows the expected pure black and pure white as expected.
In my experience then, it seems that streaking should not be a problem with normal image processing and film exposure.
clear with grain dissolver
Vuescan with Grain Dissolver
Sponsored Advertisement

Back to Tips

Take some time to enjoy the rest of the site
Send email to robert.feinman@gmail.com

© 2004 Robert D Feinman