Two A1 / D-size scanners
suitable for raster to
vector conversion: The
Contex XD2490 (top) and
the Colortrac SmartLF Ci 24.
A few years back we conducted a survey of our raster to vector conversion software users to find out what they wanted in a large format scanner. To our surprise, almost half said that an A1 / D-size wide format scanner would meet their needs. Price, as always, was the sticking point. Most wanted to pay no more than a low GBP 1000 / USD 1500.
The good news is that there are now two new 24" wide, (A1 / D-size) CIS-based (contact image sensor) wide format scanners available, both suited to scanning technical drawings for the purposes of raster to vector conversion and more besides. Both make A1 / D-size scanning available at an unprecedented low price. However, both are more expensive than our highly cost-conscious raster to vector users stated they were willing to pay.
The two new 24" wide-format scanners are the Contex XD2490 and the Colortrac SmartLF Ci 24. Both are based on wider models which have won BERTL 4.5 Star "Outstanding" awards. (We do not place much value on BERTL awards or ratings.) The best evaluation of these devices will be your own using the drawings you have on file. As most resellers still expect to give a hands-on demo, arranging an on-site evaluation in your office should not be difficult. Both the Contex and Colortrac 24" wide devices are compact and lightweight and well-suited to transportation.
The Contex XD2490 comes in at GBP 2775 / USD 3970, is fully color capable and is the only 24" model in the range. There are three Colortrac SmartLF Ci 24s - m (monochrome), c (color) and e (enhanced or faster color). The SmartLF Ci 24e costs GBP 2895 / USD 4250. Both are supplied with scanning software, the XD2490m including Nextimage SCAN. The more powerful Nextimage SCAN+COPY is a paid for extra. The SmartLF Ci 24 is supplied with the basic SmartLF All-in-One scan, copy and email software [April 2011 - now replaced by SmartWorks EZ]. ScanWorks and CopySmart [April 2011 - now combined into a new product called SmartWorks Pro] are paid for extas.
We have tested both these devices' wider stablemates, the 44" wide Contex SD4490 and the 40" wide Colortrac SmartLF Ci 40e. These CIS wide-format scanners are both well-suited to scanning technical documents, drawings and maps up to A0 / E-size in monochrome, grayscale or color. There is no reason why the smaller Contex XD2490 and the Colortrac SmartLF Ci 24 should not provide similar quality scans to their full-sized stablemates.
The biggest downside of both these 24" devices is that neither will let you scan an A0 / E-size drawing should you need to do so. This limitation is the reason why less expensive 24" scanners sell in smaller numbers than their wider, more useful, more expensive counterparts. Give your purchase of a 24" scanner some serious thought!
The fundamental difference between these 24" scanners is their design. As a cut-down version of Contex's first generation of CIS-based SD Series scanners, the XD2490 uses a traditional scanner design based on multiple rollers. These draw the document horizontally into and through the scanner from the front to exit at the back. The SmartLF Ci 24 is based on Colortrac's fourth generation Ci 40 model and is the more innovative of the two devices. It uses a single, solid roller or drum to draw the document in and roll it around the drum. Uniquely, the document exits at the front of the Ci 24, not at the back, as in every other make of scanner available today.
What front versus back media exit boils down to is that the SmartLF Ci 24 can be used more practically as a desktop scanner. Ironically, this is the role for which Contex suggests the XD2490 is best suited. Indeed, because Contex sees the XD2490 as a desktop scanner, it is not offering the option of a floorstand at present, presumably to keep the total cost down. Colortrac offers the SmartLF Ci 24 with the option of a professional floorstand, albeit for the not inconsequential added cost of GBP 345 / USD 500.
The XD2490's traditional rear exit media path means that it will eject the document out the back and over the desk which must be cleared before it can be used for desktop scanning. If your desk is anything like mine, clearing it is an unwelcome job at any time but most especially at short notice. The solution is to place the XD2490 on its own dedicated surface or on the the far side of a desk so that it feeds paper over the edge. (It has the option to hold the paper and rewind it.) However, such positioning may not make the best use of available space in a small office.
By comparison, the SmartLF Ci 24's front exit makes it more practical to use as a large format desktop scanner. Quite simply, the SmartLF Ci 24 requires no clear desk space behind it at all. If the SmartLF Ci 24 is placed on the front edge of a desk, its operational workspace occupies no more than the area taken up by its footprint. This allows it to be placed and used in confined spaces previously inaccesible to wide-format scanners, like on top of a cabinet, in a bookcase or on a shelf mounted on a wall, etc. However, before you mount your new SmartLF Ci 24 on a purpose-built shelf, you must ensure that the shelf is wide enough to allow its hood to open fully. The SmartLF Ci 24's hood opens backwards, taking up extra space. Failure to provide a wide enough shelf (mounted at a suitable height) may mean having to take it down every time it needs to be opened.
The main consequence of the SmartLF Ci 24's design is that it accepts slightly thinner media than the XD2490. The SmartLF Ci 40 and Ci 24 are restricted to a maximum of 270gsm technical document media or a thicknesses of only 0.012" (0.3mm). The maximum media thickness of the XD2490 is 0.08" (2 mm). Some readers may be perplexed by this and worry that some technical documents might be too thick for the SmartLF Ci Series. In our experience, we have not yet found a technical document drawn on standard drafting media that is too thick for the Colortrac SmartLF Ci Series to scan. Surprisingly, 0.012" (0.3mm) thickness covers almost all documents.
As stated, 24" scanners are unpopular because of the ever-present risk that they will not be able to scan larger drawings. Contex are aiming the XD2490 at AEC professionals, many of whom use smaller size architectural and construction drawings. Contex are making much of the XD2490's ability to act like a glorified fax machine for the digital age, emailing revised and scanned documents back and forth between site and head office and or between designer and client. This is an entirely practical application for some AEC professionals with smaller drawings but it is nothing new. All scanners today have a scan-to-email facility that saves documents as a PDF file for emailing.
The two devices have different maximum optical resolution, generally regarded as an indicator of image sharpness. Both offer all the image sharpness you will need for producing good quality scanned images suitable for archiving, viewing, printing, emailing but, most especially, raster to vector conversion. The XD2490's 1200 dpi optical resolution is far more than you can practically use and twice as much as the SmartLF Ci 24's 600 dpi which is still more than you are likely to use. In reality only the uninitiated will scan an A1 / D-size document at 1200 dpi or even 600 dpi in monochrome, let alone color. The resulant file will simply be too big.
Raster to vector conversion requires sharp, clear, well-defined images. Many new to raster to vector conversion and or scanning are wrongly led to believe that only high optical resolution can give scanned images the necessary degree of sharpness and detail which is needed. This is untrue. Generally, when performing raster to vector conversion on most technical drawings, you will seldom, if ever, use optical resolution any higher than 400 dpi. The only practical benefit from 1200 dpi optical resolution is in scanning small postcard or smaller size images.
Both devices are adequately fast. Contex claim that their high scan speeds increase productivity. This claim is only true when saving low resolution images for archiving, viewing or printing purposes. It is untrue when scanning for raster to vector conversion (or for quality images) where slower, more deliberate scans using editing tools must be made in order to get the best vectorization results. (See the Ghastly Gallery for examples of what can happen if you don't scan with care and attention to detail.) Good quality scans require fast and flexible scanning and post-scan editing tools. Colortrac's ScanWorks software [April 2011 - now replaced by SmartWorks], uses an intelligent "scan once, edit many" approach which, in our view, provides the best way to get sharp, clean scans that vectorize well.
Support for Gigabit Ethernet connectivity allows the SmartLF Ci 24 to easily connect to most office networks. Although the Contex XD2490 does not have Ethernet connectivity, it is supplied with a special driver that makes it easy to set up and use over a network.
These 24" models offer similar levels of price and performance and, as they are based on successful wider stablemates, pedigree. However, the comparative newness of both the Contex SD Series and the Colortrac SmartLF Ci Series means that neither system is yet old enough to claim that its technology is fully proven. Nevertheless, expect to see these products representing Contex's and Colortrac's main technical document scanners for some years to come.