Umax PowerLook 2100XL review

This review is part of a comparative test between Agfa DuoScan HiD, Microtek ArtixScan 1100 and Umax PowerLook 2100XL.

These days flatbed scanners are very much a commodity items commonly found in home setups as much as on business desktops. Less than £100 will buy you a decent scanner, but if you're prepared to pay a little more you can add on transparency adaptors and automatic document feeders for extra versatility. But this ignores the realm of professional, creative scanners which start at around £1,000. We take a closer look at three of these high-end flatbed scanners to find out exactly what they can do that a humble £100 device can't.

One thing the three products have in common is that their manufacturers - Agfa, Microtek and Umax - not only enjoy a good name in the professional graphics and pre-press industry, but they also sell low-end devices to home and business buyers. You have to wonder how a manufacturer can happily build high-end, precision machines while churning out lightweight translucent consumer scanners.

The situation is even more complicated than that. The three scanners reviewed here aren't exactly high-end scanners either. All three companies build true pre-press devices costing in excess of £4,000, so think of the £1,000 to £2,000 range as catering for marketing departments, production desks and graphic designers.

Another feature the three have in common is a SCSI interface. Although high-speed parallel ports and even USB connections are fast enough for everyday personal scanning tasks, the high resolutions handled by professional scanners demand a faster throughput.

Resolution and colour depth

The Agfa DuoScan HiD and Microtek ArtixScan 1100 are machines based upon the same basic scanning mechanism, both supporting a sampling rate of 1,000 x 2,000ppi (pixels per inch). The Umax PowerLook 2100XL supports 800 x 1,600ppi. The first figure in the pair refers to the number of pixels that can be captured per inch of the scanned original by the CCD array along the scanning arm. After this comes the increment at which the scanning arm moves along the glass plate. The optical sampling limit, therefore, is 1,000ppi for the Agfa and Microtek products and 800ppi for the Umax.

This is an important distinction, as scanning any higher than the optical limit adds absolutely no more image detail whatsoever. Instead, the scanning software just interpolates extra pixels based on adjacent colours to fill out your desired resolution. But even so, you can find plenty of consumer scanners that support 600 x 1,200ppi optical sampling, which isn't far off Umax's 800ppi - so you may be wondering what you're paying for (see Is it really worth it?).

Also note that despite its lower sampling rate, the Umax PowerLook 2100XL costs a good deal more than the other two products at £2,199. The difference in price is actually due to physical plate size, since the Umax scanner is an A3 device as opposed to the Agfa and Microtek which offer just an A4 scanning area. The kind of person who buys an A3 scanner is almost certainly looking to scan large originals which will be reduced for printing. Hence, there's no great need for ultra-high resolution captures. The 1,000ppi of the Agfa DuoScan HiD and Microtek ArtixScan 1100 makes them better optimised for scanning small originals for enlargement, especially transparencies.

Colour depth is important for professional scanning, although many manufacturers use it as just another 'big number' to print in their advertising. In effect, 24-bit colour is made up from devoting eight bits per colour (red, green and blue) per pixel. These eight bits essentially allow 256 levels of each RGB channel, the 24-bit combination ultimately representing a top potential of 256 x 256 x 256, which equals 16.7 million different colours. By increasing the number of hardware bits devoted to each pixel, a scanner should, in theory, be able to deal with a bigger overall colour space rather than 'clipping' everything it sees to fit within 256 levels.