Robert D Feinman

Optimizing Color Negative Scans on Minolta 5400
and Similar Scanners

As has been pointed out in several other topics here, the software that is provided with the Minolta Elite 5400 and several other models is inadequate for high quality scans of color negatives.

Fortunately there is a third-party solution: Vuescan from Hamrick software.

By setting the parameters within this software to capture all the dynamic range (clipping levels set to zero) we get a scan that looks like this.

Original Image
As Scanned

The image looks dark and low in contrast. This is to be expected since the color negatives have less maximum density and a smaller range of densities than slide film.

These settings have to allow for the range of transparencies thus we are only using part of the capture potential of the scanner.

To avoid problems later on it may be a good idea to capture in 16 bits per channel.

See my discussion of this in another tip.

Scanned Histogram
As Scanned Histogram

The simplest approach to fixing this is to apply the auto adjustment in the curves or levels dialog.

Here is the result of doing that. The contrast and brightness are much better, but the image still appears a little flat and slightly bluish.

Auto curves
Auto Levels Applied
Notice the tonalities are much better distributed over the range from black to white. There is some posterization visible in the histogram, since we are only using 8 bits per channel. This may not be visible in the image, however.
Auto curves histogram
Auto Levels Histogram
The next approach is to set the black, white and gray points using the eyedroppers in the curves dialog.

We used the third from the left gray square in the bottom row for the neutral tone. The first square was used for the white point. The shadows behind the card were used for the black point.

Once again the contrast is improved and the blue cast is removed.
Set black, white, gray points
Set Black, White & Gray Points

This approach spreads the tones over a wider range than the auto levels approach. This can be adjusted by changing the preferences in Photoshop for the clipping points and the RGB values of the three eyedroppers.

We usually set the white level at 253 and the black at 5 to avoid blocked up tonalities when using the auto tools.

black,white, gray histogram
  Black, White, Gray Points Histogram

For this approach we set a point in the image with the eyedropper tool where we wish the black and white values to be.

Then keeping an eye on the info panel we shift the end points to bring these to the desired values.

In our case, white about 253 and black about 5. We can observe the effect on the image as we make the adjustments.

The steep curve shown here will make a much more contrasty image that the prior techniques. We are doing this for aesthetic reasons.

manual curve
Manually Set Curves
While the adjustment shown above will fix the contrast it doesn't address the color balance. So we apply a second set of curves.

By setting markers on the row of gray squares along the bottom of the card we can make adjustments at each gray level to neutralize the color balance.

This is more exact that just using one point as is done with the gray eyedropper.

Here is the blue curve.
blue balance
Blue Curve
Here is the green curve. The deviations from a straight line are much smaller.

green balance
Green Curve
Here is the red curve. Notice the upward adjustment in the darkest tones.

This type of adjustment can also be done to control specific colors that don't reproduce properly.

red curve
Red Curve

This is the final image after the contrast and color balance curves have been applied.

There are a full range of tonalities shown, the gray patches are all neutral and the colors have been given a lot of  "punch".

There are still some color reproduction problems, specifically the yellowish square that is in the second row and is second from the right should be yellow green. This may be a failure of the film to capture the colors correctly or a problem with the profile used to characterize the scanner.

So there are still some judgments to be make in the choice of film!

Even so, we now have a way to capture all the tonality in the negative. This is a big improvement over the solutions shown using only the Minolta supplied software.

final image
Final Image
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© 2003 Robert D Feinman