scanned slides don't have shadow detail

A correct exposed slide is a pleasure to look at when projected. When

I want to make a scan of it with my minolta dimage scan dual II there

is little left of it.

When I use the automatic way of scanning the correct exposed slides

look underexposed, so I make a prescan, using the image correction I

select the brightness range I need and still the shadows are gone.

I can get more out of the shadows lowering the contrast but then the

image has no more 'power'.

It is known that kodachrome is hard to scan but that is concerning

colour correction as far as I know.

To illustrate my problem, a picture in annex on which the eyes became

invisible while project they are ok.

Kodachrome is very contrasty (at least the 64 is), so this could explain the problem you're having. Do you try to adjust the scan with brightness/contrast settings? These, while they look attractive, don't work. You have to use the histogram display and adjust the endpoints of the conversion curve for the RGB data to get a good result. Have you tried multi-scanning?

 

It could be that the scanner isn't good enough; a Nikon LS-4000 probably can see a lot more than the Minolta, although the price is also different.

However, there is detail visible in the eyes when I blow that picture up in Photoshop, so your scanner is capable of reading it.

Probabely kodachrome is too contrasty, a few minutes earlier I made a b&w picture in the same high contrast circomstances which scans perfectly (annex).

I always use the histograms which are handy.

Multiscanning is probabely the solution.

Thanks,

I ran into this problem - though using an Epson faltbed. Then, instead of the Epson driver, I used Vuescan running under Mac OSX and the difference was remarkable - tread on tyres came out, reflections on dark ponds came up. Once I'd seen it done I was able to duplicate the result adjusting settings in the original Twain driver - but it took hours of fiddling with settings, and constant comparing to the Vuescan results. I really dont undersand why Epson engineers cant achieve the same results with their drivers.

 

If you haven't tried it already, have alook at Vuescan - it's a free download to try out, and less than 2MB.

 

Something else I have always found useful - Photoshop (etc.) can always bring more detail out of 'black' but not out of overexposed areas, so I usually try and get darker images out of the scanner and lighten them.

Using VueScan, I suggest you try the "Gamma" option, which seems to give the longest tonal range. Adjust the brightness and white point accordingly.

 

<p>If you make sure to scan a portion of the film edge, then you will have a sample of something that really <i>should</i> be at 0% brightness.

I concur with Dudley re Vuescan. I have the same scanner, and have scanned 1800 black and white neg's. with Minoltas software (lamentable) and spent hours cloning out dust and scratches from the results (horrific), before stepping back and taking a second look at the tone range and image quality. Minoltas defaults producing very harsh, clipped and posterized results, sometimes so-so, sometimes akin to second generation photocopy.

 

I'm currently redoing the entire (8 month) exercise (about 5 rolls in, 50~ to go), using Vuescan. My approach:

 

 

In Vuescan:

 

- Scan emulsion up. Vuescan has a mirror setting. It's tricky placing neg's in holder but the scanner is above the film, I believe focus and detail is better this way.

- Autofocus with each, at center. Hamrick (Vuescan author) suggests focussing off center focus, but this works for me. Try manually focus the preview image at various points and note the numbers it gives you. Often the center is more or less average. Also, your subject is probably near center. If you focus toward corner, you can actually be way off.

- Scan as image (for black and white negative, for color neg, I got better result with color negative, generic. Haven't tried slide yet), 48 bit rgb (in files tab)

- set white balance, log (dark)*, no clipping (in color tab)

* For my black and white negs. this seems most satisfactory most of time.

- Save as 48 bit rgb tiff, no compression. Also save the raw file, since if log (dark) setting in color tab is not satisfactory, you can scan "from disk" with vuescan: re-scanning this raw file trying log (med) or gamma. Save these files in a subdirectory, and do photoshop adjustments on a copy. Blow away the subdirectory only after completion of the roll, if you need the space.

 

In Photoshop:

 

- Invert (tone range, for black and white negs.)

- Rotate as needed

- Auto Levels with preset 0.1% clip rgb channels individually

- Convert to greyscale

 

(note, the above can be done in an automated batch)

 

Then, go back through the roll, apply a curve or move the tone mid-point (in levels) a little IF needed. If it's need a lot, try rescanning "from disk" with gamma or log (med)

Thanks a lot everybody, It seems the vuescan software is a good tool, I'll take a look at it at photokina later this week and I have to invest in fine tuning my equipment.

Try Analog gain if you have it on the Minolta scanner. I use it with Kodachrome 64 on my coolscan V ED and it brings up the shadow detail nicely.