| User test by Mick Murphy |
For me, the basic prerequisite in choosing a new scanner is a well-endowed dynamic range. I've learnt this from using my existing scanner, a Nikon Coolscan II, that simply can't cope with dense or contrasty slides. Carefully exposed sunsets turn into virtual silhouettes and landscapes taken in less extreme lighting have dense, murky shadows. No amount of tweaking in the scanner software or in Photoshop can capture the shadow details, which are plainly visible on the slides.
This is not a fault with the Coolscan II, but a consequence of its low dynamic range, a property that determines a scanner's ability to capture shadow detail. Dynamic range is measured by a mysterious parameter, D, which ranges from less than 3.0 up to 3.6 in top of the range desktop scanners.
Any scanner sporting a dynamic range of 3.6D will undoubtedly be satisfactory in other quality-determining departments, such as maximum resolution and bit depth. As a Nikon fan, my first thoughts went towards the Nikon Coolscan LS2000, which is well-specified, but has a street price of between 1000- 1200. The alternatives are Minolta's new Scan Elite at around 800 or their older Scan Speed, which has halved in price to 500 since the advent of the Scan Elite.
These two Minolta scanners appear very similar in their basic specifications, with a dynamic range of 3.6D and 2820ppi maximum resolution. The main difference seems to be that the Scan Elite, like the Nikon Coolscan LS2000, offers batch scanning and comes with Digital Ice automatic scratch-removing software. With no real need for batch scanning or Digital Ice, and pushing brand loyalty to Nikon aside, the Scan Speed won my vote, particularly as it has received good reviews in the photographic press. The bonus came when my local photographic retailer had the Scan Speed in stock and on special offer for 439.
Using the Scan Speed
Setting up the scanner is simple. Just follow the instructions in the paper manuals to install the software, plug the SCSI connector in and off you go. Everything worked first time with no hassle. If you haven't got a SCSI card installed, you will need to buy one of the Adaptec cards recommended by Minolta for about 50. The scanner comes with Adobe Photoshop 5 LE, a bonus if you don't already have good quality imaging software.
The scanning software works as a standalone or as a TWAIN plug-in in Photoshop. Although it has been superseded in terms of speed by the Scan Elite, the Scan Speed remains pretty nippy, producing a maximum resolution scan in about 45 seconds and a prescan in about 12 seconds.
The user interface is simple and intuitive, with online help readily available. Holding the mouse over any of the controls brings up an explanation of its function. The controls are logically arranged in three groups. A top bar includes buttons for prescan, scan, choice of film type, general preferences and job type.
The job function is particularly useful if you are new to film scanning, allowing you to choose from a range of resolution settings, depending on the intended use (e.g. web, inkjet printer) and desired output size of the image. You can also save your own commonly used settings as jobs. A side bar has buttons for modifying the prescan, the most important of which control the tonal range and colour balance. The resolution settings are accessed by a set of drop-down menus.
There are three different controls for modifying the colour balance and tonal range.
The Variations dialog box provides a simple visual method for modifying the prescan and is a very useful tool if you are inexperienced at making tonal and colour adjustments. Click on one of the thumbnail images, which display slight variations on the original image in the centre. The Tone Curves dialog box is similar to that in Photoshop, allowing you to modify the tonal range in each of the colour channels, individually or simultaneously, for precise control of colour balance and contrast.
The Histograms dialog box performs exactly the same function as Tone Curves but uses sets of sliders instead of curves to allow very precise colour and tonal adjustments to the prescan image. The sliders can be moved simultaneously for overall tonal adjustment or individually for precise modification of the colour and tonal values in highlight, midtone and shadow areas.
Despite the good range of tools for image modification at the prescan stage, it is often much easier to perform these tasks on a larger image, using adjustment layers in Photoshop, providing that the scan is not too far out in colour and tonal range and has captured all of the important details. The auto exposure function, accessed through the Preferences dialog box, provides very acceptable results in many cases, requiring only minor tweaking in Photoshop. This works well even for very dense slides retaining detail in all but the darkest areas of the image.
This image was scanned using auto exposure. The levels command in Photoshop has been used to lighten the image slightly to show detail in the grass and rocks in the foreground. Minor modification has been to the colour balance and saturation and an unsharp mask applied.
However, for slides where it is important to retain detail in highlight areas, you will probably get better results by turning auto exposure off. This produces a darker image than with auto exposure on but retains good highlight detail. The shadow areas will also be darker, but the scanner is very good at retaining shadow details, which are easily recovered using the levels command in Photoshop.
This very contrasty image shows black, volcanic debris lying on snow and glacial ice. This scan was made with auto exposure on. The shadow areas are well-exposed and there is a weak magenta colour cast. However, detail is lost in the snow that cannot be recaptured by adjustment in Photoshop.
In order to capture the detail in the snow, adjustments would have to made at the prescan stage. The scan was made with auto exposure off. It has a moderate bluish-magenta cast and the shadow areas are dark. However there is good detail in the snow compared to the auto scan.
This image was made from the manual exposure scan by using the Levels command in Photoshop to lighten the shadow areas and the Colour Balance command to correct the colour cast. There is no noticeable loss of shadow detail compared to the scan made with auto exposure on.
Having sung the Scan Speed's praises, it's time to reveal its faults. The only complaint I have is about the mechanism for loading mounted slides. The slides sit in a holder but there is no way to ensure precise alignment, except by trial and error, usually after a few prescans. For many images, absolutely precise alignment is not a problem but it is important if you are trying to scan the full area of the image or keep carefully levelled horizons horizontal. However, the trial and error method does work and doesn't take too long, as prescans are fast.
It's a rare and satisfying feeling when you buy a piece of equipment that meets all your requirements in terms of quality, but which costs less than half the amount you had expected to pay. The Scan Speed's ability to deal with dense and contrasty slides is impressive for a machine costing less than 500. If you are a photographer who uses digital technology to scan and print 35mm slides and you need a high quality desktop scanner that won't break the bank, then the Scan Speed should be a strong contender for a place on your desktop.