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35mm Scanners

Film scanners aimed at amateur and professional photographers are mainly for 35mm slides and negatives. Film scanners use a light source on one side of the film and the photosensitive cell on the other. In most the film moves across to produce the different scan lines, though some work by moving light source and cell as in a flatbed.

Most will take slides in normal mounts, as well as strips of negatives and transparencies. A few models only will cope with negatives longer than the standard 36mm, so if you use a panoramic format camera such as the Hassleblad XPan, your choices will be limited. Some come with holders that will take APS.

Input resolution

Since the original is so small, film scanners need higher resolution figures than flatbeds which are generally used with large originals. A rough guide to the resolution you need is given by multiplying the smaller dimension of the print by 300. So to make 8x10 prints, a resolution of 8x300, which is 2400 ppi, is satisfactory.

You can make bigger prints than this suggests, but the quality will not be optimum. For professional use, a resolution of 4000 or 4800 ppi is probably essential.

The quality of scans produced from film scanners is very dependent on the light source, the optics used, the mechanical design and build quality, and in particular on the design of the slide or negative holder. It is not surprising that the best-known makes in cameras are also some of the best-known in film scanners, including Minolta, Canon and Nikon. Microtek have also made some good film scanners, both under their own name and also for Polaroid and other companies.

Medium Format

Medium format scanners can also scan smaller sizes such as 35mm. Not surprisingly, they are larger and more expensive than 35mm models. A lower resolution is fine for scanning larger negatives - few purposes will need more than 3600 ppi from 120 film.

One of the most affordable of these is the Minolta Dimage Scan Multi Pro, which attracted some lukewarm reviews when first introduced. Many of its apparent shortcomings were shown by users to be caused by the software, and an active Multi-Pro User Group prodded Minolta to make improvements. With the new software, it is a much better piece of equipment, although third-party software will still generally get more from it.

Software Problems

Many of the problems photographers have had with scanners come down to a perception by manufacturers of them as 'slide scanners'. Most photographers prefer to shoot on negative, and many have turned to scanners as a way to enable them to do so, while providing clients with positive images on CD-R. Although negatives are actually easier to scan because the densities are less extreme, both the hardware and the software needs to be geared to this use.

The solution favoured by some manufacturers has been to include third party scanner software, sometimes charging a premium price for it. The well-regarded SilverFast software (see below) has been included with some 35mm scanners from Nikon and Microtek. Many users have also turned to third-party software, including the relatively inexpensive Vuescan, covered in detail in the last part of this feature, Scanning Software.