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Scanner Software

Software from different manufacturers generally provides similar features but may look rather different. There are two programs from independents I recommend for use with film scanners.

If you want to be able to scan from your transparencies and produce good quality 24bit images more or less automatically (once you have set up the process), then there is little reason to look further than Silverfast AI, if it supports your scanner.

If your main interest is in scanning negatives, then you may find Vuescan gives the best result, although you can expect to do a little tweaking of its 16 bit scans in Photoshop or your favourite graphics software. Before buying any film scanner I'd advise checking that it is on the list of around 200 scanners Vuescan supports.

How to get the most from your scans

You can check you are getting the most from your scanner and the software provided with it by downloading a trial version of Vuescan, available for both Windows and Mac. This installs in its own folder and makes no other changes to your system, so is easily be removed if you decide you want rid of it. The trial version produces scans with an intrusive overlay, useless except to compare with scans from the manufacturer-supplied software - exactly what you need to do.

Setting up Vuescan

Vuescan has an off-putting interface, with many settings on the half-dozen tabs which display on the left of its window. By default it hides many of the settings, but gives you a button to click to show all. It should detect your scanner, and the first settings on the Input tab to select media type, resolution and frame number are obvious.

Still on the Input tab, I normally select the 'Scan from Preview' option, which speeds up scanning by making only one pass across the film. Obviously you need to set the preview resolution at the output resolution you require when doing this. You should normally also choose to focus on preview.

For most of the other settings you can start with the default values, although you may like to go to the Color tab and select the actual film type in use if it is one of the listed options. For films not included (and the list is now in need of updating) either choose a similar film or the generic settings. (Vuescan Professional can also make and use an IT8 film profile if you have a suitable target to scan.)

Although some find the interface confusing, it is very logical, and to choose the directory to output your scans, you go to the Output tab.

Scanner Calibration and Preview

You are then ready to calibrate your scanner. Go to the Scanner menu at the top of the window and choose calibrate. While the scanner performs this, you can put your negative into the carrier ready to make the scan. Once the calibration is finished, insert the carrier and select a preview - the button at bottom left is convenient. This is actually the final scan if you have selected 'Scan from Preview' as suggested, so it will take a while before the preview image appears.

Changing the Preview

Start by checking the preview image and make any necessary adjustments to the brightness setting, (on the Color tab, choose 'All' under More Options if it is not visible) although the auto-exposure is usually fairly close.

Accurate focus is obviously vital for good scans. An advantage of previewing at the scan resolution is that it enables you to zoom into the preview image and check it is sharp. You may occasionally find that scanner software fails to focus correctly, perhaps because there is no suitable detail in the area picked for focus. If this happens with Vuescan, simply drag the focus indicator to an important part of your image and repeat the preview. If you didn't select auto focus on preview, you will need to focus manually first using the Scanner menu.

Using the histogram

The basic tool for understanding what your scanner is doing is the histogram. Look at it using the 'Preview hist' tab above the preview image. The histogram represents the tones in your image as a bar chart, from dark to light. For colour images you can see the three colours separately, but generally it is enough to look at the combined RGB curve. The example shows the very clear view histograms from Vuescan.

Preview histogram display from Vuescan.

The curve should start at zero at the left hand axis (black) and finish at zero at the right hand axis (white.) If there is a gap between the axis and the start of the curve, you should increase the black point setting, while a gap at the right end of the curve means the white point setting is too low. The controls for making these changes are on the Colour tab.

For this particular image, my usual settings were pretty close. The Vuescan default settings give considerable more white point clipping than I like, and a figure close to zero works for most of my negatives. The histogram shows a small amount of clipping at the left hand side (black) where the blue and green curves have not quite dropped to zero, although they are very close.

If the curve does not fall more or less to zero at either end, even after you have adjusted the exposure and black and white points, then the image you are scanning has a greater range than your scanner can handle. This can happen with some overdeveloped or overexposed materials. Some scanners can handle a greater range if you scan negatives as slides. Unless you make the histogram fit the chart properly you will not get a high quality scan.

Final touches - EditLab 4.0

You can make other adjustments to your scan in the software, but if like me you like to finish the process in Photoshop, then so long as you fit the histogram and output in 16 bits per channel, there is little point in doing more at this stage.

Editing of 16 bit images can be done more or less without loss, while when you only have 8 bits to work with, it is easy to get images that show clear jumps in tones as adjustments tend to reduce the total number of colours.

You never know quite who you will meet in South London. 21mm, Hexar RF.

This is the image whose histogram was shown above, after a couple of tweaks with EditLab 4.0.

Vuescan handles colour balance automatically for both positives and negatives. With some other software you may need to adjust the colour balance, perhaps by selecting a neutral tone in the image. The problem is that many images have no true neutral, or there are several possible candidates that give different results. Vuescan generally does a good job, but is not always perfect.

I prefer to let Vuescan do its best, then to balance finally in Photoshop, preferably using the Pictographics iCorrect EditLab 4.0 plugin which usually gets a great balance with minimal effort, even for those tricky images. It does a great job, not just of correcting neutrals, but also allowing you to match reference points such as flesh, foliage and blue sky for both hue and saturation. The jpeg shown here is not quite the same colour as the tiff file, which has good neutrals.

Buying Vuescan

Vuescan is software sold online by its author, Ed Hamrick. Its sales have built up over the years largely through word of mouth among those of us who scan negatives. Most of those who tried it bought a copy immediately, as I did. It is now available in two versions, Standard and Professional, with the professional version adding support for ICC profiles, raw scans and IT8 colour calibration and a year's free upgrades (they come fast and furious, but only take a few seconds to download and install.)

Some of the upgrades add fix bugs; others add new features or improve the existing ones, often in response to user suggestions which the author obviously takes very seriously. Unlike most other scanner software, Vuescan is a standalone program rather than a twain module. This means you can happily keep on scanning images in one window while using your graphics software to edit in another, although since both can be very processor intensive your work will slow at times. Although not the absolute bargain it used to be, Vuescan is still a very useful piece of software.