Scan2CAD raster to vector conversion software

Buying a wide format scanner

You may have some questions about buying a wide format scanner. We did!

The information below is largely based on our experience of buying, using and ultimately selling large format scanners for use in CAD applications.

Do I really need to buy a large format scanner?
Who are the main scanner manufacturers for CAD?
Which scanner models should I consider?
What should I look for in a scanner?

Disclaimer

Do I really need to buy a large format scanner?

The cost of wide format scanners has fallen BUT do you really need one?

How many scans will you do in one, two and three years? Can you really justify buying a +- £5000 large format scanner based on these volumes?

If you need a scanner but cost is an issue, why not lease a scanner?

Finally, consider the used equipment market. There's a lot of good but older generation kit around. Click here for a list of second-hand equipment for sale at attractive prices.

Who are the main scanner manufacturers for CAD?

Contex - www.contex.com

(Also branded under GTCO/Calcomp, HP, IDEAL, Océ and Vidar.)

Contex HD4230
Contex HD4230

Contex Scanning Technology are a Danish company who introduced their first monochrome (black and white) scanner in 1988. Today they are the leading manufacturer of large format scanners and scanner software for both colour and monochrome scanning solutions in the world.

Contex wide format scanners are also branded under GTCO/Calcomp, HP, IDEAL, Océ and Vidar names. With some justification Contex describe themselves as "the most dominant solution in wide format scanning". At one time they claimed to have had "control of 92% of the wide format market".

Until mid-2008 Contex's product range was based exclusively on CCD technology. For a long time Contex dismissed the emerging CIS technolgy as unsuitable. Eventually Contex were forced to recognise that rival companies, products and technologies were taking market share from them.

Contex responded by upgrading their CCD-based product line to the new, more competitive HD Series with 600 dpi optical resolution and by introducing their first generation of CIS-based scanners, the SD Series, with a very impressive specification that includes the first true 1200 dpi optical resolution in any scanner.

Colortrac - www.colortrac.com

(Also branded under imagePRO by Paradigm.)

Colortrac is a British company based in St Ives near Cambridge, England. It was founded in 1989 to develop digital large format scanning solutions for the oil exploration industry.

Colortrac SmartLF Gx 25


Colortrac SmartLF Gx 25

Colortrac made notable technical breakthroughs in the development of expensive wide format scanners for the specialist reprographics market but remained relatively unknown despite winning a Queen's Award for Export Achievement and acquiring the better-known ANAtech brand in 1999. Now the Colortrac brand is in the ascendant.

Colortrac's big break came when they identified an emerging opportunity for large format scanners among cost-conscious professionals at the low end of the market. In June 2004 they announced the Colortrac SmartLF 4080 series of aggressively priced wide format CIS scanners. This had an immediate impact on the market. In 2005 the SmartLF made Colortrac the fastest growing large format scanner manufacturer worldwide.

In February 2006 Colortrac announced the replacement of the popular 4080 CIS series with a new and improved SmartLF Cx 40 CIS range. The Cx 40 raised the bar on technical standards while retaining the same aggressive price as the old 4080 series.

In September 2006 Colortrac upped the ante again with the introduction of the SmartLF Gx 42 CCD series. Now, for the first time, Contex has a CCD competitor with innovative new CCD technology and the means and the will to bring it to the market at an aggressive price.

Graphtec - www.graphteccorp.com

(Also branded under KIP and under Quatra by Paradigm.)

Founded in 1949, Graphtec Corporation, Yokohama, Japan, is a respected industry leader in cutting plotters, flatbed cutters, wide format printers and scanners, digital data acquisition and test instruments.


The Graphtec SK200 as part
of Paradigm's BERTL Award
winning EIS Supra MFP system.

Graphtec corportate philosophy emphasises the pride employees must take in the company's products. This is seen in the superb engineering quality of their CIS scanners which have the best support warranties available today. Unlike Colortrac and Contex who invest in both CIS and CCD scanner technologies, Graphtec is committed to CIS imaging only which it believes is best for both technical drawing and graphics scanning.

While many will disagree that they are the best for graphics artwork, the quality of Graphtec's colour CIS scans is impressive enough to challenge the cosy assumptions of its CCD-based rivals.

Graphtec have recently enjoyed success in the OEM market with the SK200 scanner. They now believe that they can increase their market share considerably with new scanners that were released in April 2008. It remains to be seen if these expensive, proven but traditional devices can cut the mustard in a fast changing market. While hardware quality is undoubtedly a Graphtec strength, their software solution is poor.

Image Access - www.imageaccess.de

(Also branded under Infinity WF by Bowe Bell + Howell.)

Founded in 1993, Germany's Image Access GmbH is the newest of the large format scanner manufacturers.

Image Access WideTEK 36


Image Access WideTEK 36

Image Access has a distinguished technical pedigree. As early as 1993 their HiRES graphics card series combined a 1680 x 1200 pixel resolution with an outstanding low price. Their next product was a PCI HiSCAN scanner card which connected nearly all scanners with a video interface. By 1996 Image Access was developing hardware components for the manufacture of microfilm readers, copiers and scanners.

In 1997 Image Access' Bookeye Planetary Scanner revolutionised the way that documents are captured in libraries, universities and museums, etc., worldwide. Today the Bookeye family is a market leading brand. Another milestone was the development of high-speed cameras and electronics for Agfa whose Hybrid Scanner SC51 scanned 240 documents/minute, double-sided at 200 dpi and 120 dpm, double-sided at 400 dpi.

In 2000 Image Access began development of radical, new intelligent scan technology - Scan2Net. By 2003 this technology permitted the release of a Scan2Net A2 scanner under the new product name of WideTEK. Since then the software and scanners have been improved, enhanced and sold in growing numbers. CeBIT 2007 saw the release of the new large format WideTEK 36 with the WideTEK 42 and WideTEK 48 making their debuts at CeBIT 2008.

German excellence in engineering makes this product the one to watch!

Shapemakers - www.theshapemakers.com

Established in 1995 in Queensland, Australia, Shapemakers is the manufacturer of the most unique and most affordable large format desktop colour scanning system... the Deskan 6.

Shapemakers Deskan


Shapemakers Deskan

Designed by an accredited member of the Australian Design Institute and developed and refined over several years, the Deskan uses an A4 motorised scanner that moves down a specially calibrated guide to capture a wide format drawing in several strips. Each strip is saved, automatically corrected for distortion and joined by stitching software that recognises special control points. Because no moving part of the Deskan scanner comes into contact with the image it is truly suitable for scanning delicate or damaged media.

Popular worldwide, the Deskan has especially strong appeal in emerging countries where the need for a low to medium volume large format colour scanning solution at a fraction of the price of comparable conventional A0 and E-size scanners is paramount. One fast emerging market for the Deskan is among CNC companies wanting affordable and flexible wide format scanning. Deskan FastParts offers cutting businesses an affordable scan-to-vector DXF solution that can be used to reverse engineer parts quickly and cost-effectively for accurate reproduction.

Shapemakers is Brisbane's oldest and most respected wholesale sign service bureau specialising in the manufacture of quality custom-made products for the sign industry. Shapemakers' routers, machining centers and laser cutting equipment can complete almost any type of CNC and cutting job. Shapemakers is also the manufacturer of Pictobraille (Building Code of Australia Compliant Braille and tactile signage products), Tactile Ground Surface Indicators, Stair Nosing and a distributor of Scan2CAD raster to vector conversion software.

Widecom - www.widecom.com

The 1990s were the heyday of the Widecom Group, a relatively successful Indo-Canadian manufacturer who established a public limited company in Canada in 1991. Despite largely shutting up shop in 2003, they have a web site that creates the appearance that they still trade. It appears not to have been updated since 2003.

Widecom were a pioneer of CIS (contact image sensor) technology manufacturing proprietary SLC (Single Line Contact) technology large format scanners from 1992. Today, CIS optical image sensing technology is the technical drawing scanning standard which has replaced traditional CCD (charge coupled device) scanners using cameras and mirrors. Widecom influenced CIS's development but failed to profit from it.

During the mid-90s Widecom introduced several "firsts", like their Image Database File Management System for distributing large format engineering documents across the Internet. This was followed with what they claimed was the "World's Fastest Large Document Scanner", the SLC1036C color scanner and the "World's Widest Scanner", the 72" wide SLC972C color scanner with an ability to scan up to 1/2-inch thick originals on foam board or cardboard. All impressive achievements.

Today Widecom's technology is long in the tooth compared to that of Colortrac, Contex, Graphtec and Image Access. Unlike these wide format scanner manufacturers who are a constant, reliable source of new large format scanners, Widecom has faded away to who knows where. It seems that they run a skeleton office to keep up appearances. This is not enough. On current specifications their products are uncompetitive. We question who would buy them now and, if they are still sold, who would support them?

On that basis, we cannot recommend Widecom scanners until they introduce new products. We do not include Widecom in our Large Format Scanner Comparison Chart and carry only limited technical and historical information on their products.

Which scanner models should I consider?

We've prepared a handy large format scanner comparison chart that lists over 45 different large format scanner models manufactured by Contex, Colortrac, Graphtec, Image Access and Shapemakers. For each model it shows the UK and US list price, floorstand price, scanning software price, type of paper feed, imaging system used, illumination used, colour capability, scan width, maximum media thickness, optical resolution, scan speed, accuracy, upgrade options, Energy Star compliance, connectivity, networkability, supported operating systems, weight, dimensions, supplied warranty details and country of manufacture for each model.

To receive your copy, click here.

What should I look for in a scanner?

Paper Feed

Sheet-fed - the drawing passes through the scanner

Sheet-fed - the drawing
passes through the scanner.

This scanner is face-up - the
document is fed into it with
the side to be scanned
facing upwards.


Deskan - the scanner passes over the drawing
Deskan - the scanner
passes over the drawing.

All large format scanners except the Shapemakers Deskan are sheet-fed. This means that you insert the drawing to be scanned into the front of the scanner. During scanning, the scanner's transport system pulls the drawing through the scanner to the back.

Most sheet-fed scanners are face-down - i.e. the paper is fed into the scanner upside-down. However there is a growing trend for scanners to be face-up so you can see the document as it is being scanned.

The Shapemakers Deskan is different from all other scanners. The drawing to be scanned is placed on a flat surface. The scanner, which comprises an A4 / A size motorised scan head with guide, is placed over it. The drawing is then scanned in strips which are stitched together by the scanning software.

The benefits of the Deskan are that it is the least expensive large format scanning solution, is very transportable and is good for delicate drawings that can be damaged by a sheet-fed scanner's transport system. The disadvantage of the Deskan is that it is relatively slow to use.

Imaging System

There are two imaging systems used in large format scanners - CCD and CIS.

CCD is the traditional imaging system used in large format scanners and involves a combination of lenses, lights and mirrors.

Contex HD and Colortrac SmartLF Gx scanners use traditional CCD technology with flourescent lamps. Flourescent lamps have two disadvantages. First, they require a comparatively long warm-up time to stabalise and capture colours accurately. Second, they are classified and sold as consumables as they are expected to burn out and die after a period of usage. Image Access have got around the disadvantages of flourescent lamps by using bright white LEDs in their CCD scanners instead.

Colortrac SmartLF Cx scanners, Contex SD scanners and Graphtec scanners use CIS technology. CIS scanners have no lenses, lights or mirrors, make greater use of digital electronics and use integrated RGB LEDs for illumination. This makes them cheaper to build, less heavy, more robust and means they can be used almost immediately after power-on.

Proponents of CCD technology will argue that CIS devices are not as good at scanning folded or wrinkled drawings as CCD scanners because their lower depth of focus means they cannot focus on bits of the drawing that are further away from the sensors. By the same token, feeding folded, wrinkled drawings through a CCD scanner is more likely to result in a stitching error, where parts of the drawing scanned by different cameras within the scanner do not line up! (See Large format scanner accuracy and calibration.)

Scanners that use CIS technology produce sharper scans than CCD scanners, but CCD scanners normally have a wider colour gamut (range of colours) and a higher dynamic range (ability to capture smooth gradations of tone across the entire tonal range between black and white).

This makes CIS scanners ideal for CAD users with technical drawings, where capturing a wide range of colours or tonal ranges is unlikely to be an issue. However in a reprographics, graphic art or photographic environment you should probably look at a CCD scanner. That said, Graphtec claim that their high end CIS scanners (CS510 and CS610) are as capable of high quality colour as CCD scanners.

Colour Capability

Do you need colour or not?

Most CAD drawings are black and white. However, our experience is that most CAD users buy colour scanners because most CAD users expect to have to scan in colour at some stage.

If you have a colour requirement, CAD work does not warrant the use of a high performance, reprographics quality colour scanner. Any colour scanner in our large format scanner comparison chart is capable of providing colour scans suitable for CAD.

Large format scanners are offered with the following colour options:

  • Monochrome (black and white, greyscale) only with no colour:

    Colortrac SmartLF m models
    Contex SD4410
    Graphtec IS210 Base and Pro

  • Monochrome and 8-bit colour (256 colours) - more than enough for CAD:

    Graphtec IS210 Pro LC

  • Monochrome and slow 24-bit colour (16.7 million colours).
  • Monochrome and fast 24-bit colour (16.7 million colours).

Within any manufacturer's range, monochrome scanners cost less than colour ones. The faster the colour scanning speed, the more expensive the scanner.

Colortrac monochrome scanners can be upgraded to colour. In addition, most slow colour scanners can be upgraded to fast colour.

If you need colour but your colour volumes are low, get a slow colour scanner. There will be no improvement in scan quality when you buy a fast colour scanner. It just scans faster. Sometimes too fast! See Scan Speed, below.

A final note about colour: When reading about different scanners you'll find mention that some of them scan in 48-bit colour. What this means is that the scanner scans in over 281 trillion colours (48-bit mode) and then chooses the "best" 16.7 million colours (24-bit mode), which it saves. This is of absolutely zero importance for scanning technical drawings and should not be part of your consideration! Even if colour is important to you, 36-bit colour is more than enough to capture the entire tonal range it is possible to get in the medium capable of holding the widest range of colours (film transparencies).

Scan Width

The scanner you buy should have a scan width large enough to scan your drawings.

The Graphtec CS510-06 has a scan width of 24". The Colortrac Gx 25 series and Contex HD2530 have scan widths of 25". These scanners are large enough to scan A1 / D size drawings in portrait (A1 = 24" x 33", D = 22" x 34").

All the other scanners in our large format scanner comparison chart have scan widths greater than 34" and are capable of scanning A0 / E size drawings in portrait (A0 = 33" x 47", E = 34" x 44").

There are two scanners that will scan A0 / E size sheets in landscape - the Contex HD5450 and the Image Access WideTEK 48.

The Contex SD series will scan E size sheets in landscape but is just too short for A0 size. While it will accept media up to 47" its scan width is 44". This means that while you can physically feed an A0 sheet into it in landscape, the imaging area will most likely be too short to capture the entire drawing.

Scan Thickness

What is the thickest size of paper or board you want to scan?

Most CAD users scanning technical drawings do not need to scan thick media like cardboard. Most CAD users will be exclusively scanning standard thickness paper sheets.

Most scanners are limited to scanning thin media, i.e. standard thickness paper sheets ranging from 0.8 mm (the Graphtec SK200) to 3 mm (the Image Access WideTEK range). 0.8 mm is the equivalent thickness of approximately 8 sheets of standard 80 gsm copying paper.

If you want to scan thick media, Contex HD and HP scanners accept media up to 15mm thick and the Shapemakers Deskan can scan media up to 20mm thick. Both Colortrac and Graphtec also produce scanner options that will accept media up to 20mm thick (Colortrac GxT and Graphtec CS610).

Resolution

There are two types of resolution, optical and interpolated.

Optical resolution is the only type of resolution that matters, as this is the resolution at which your drawings are actually scanned.

The optical resolution you need will depend on your drawings. In our experience 200 to 400 dpi is optimal for most CAD drawings. We recommend that you choose a large format scanner with an optical resolution of at least 400 dpi.

Interpolated resolution increases the scanned resolution of an image by calculating (making up!) new pixels to fill in between the scanned pixels. All it does is increase the size of the image without adding detail from the original drawing. It does NOT create a better quality image.

Large format scanner manufacturers and their representatives are often creative with scanner resolution descriptions:

  • Colortrac advertise their SmartLF Gx scanners as having 1200 dpi resolution.

    Although Gx scanners capture 1200 x 600 dpi, this is actually saved as 600 x 600 dpi. Scanners4CAD believe that Colortrac should describe their Gx scanners as having 600 dpi optical resolution.

  • Until recently, most Contex scanners had an optical resolution of 508 dpi but were described as having a "real" resolution (or even optical resolution, on some brochures) of 600 dpi. The Contex Puma, which had an optical resolution of 600 dpi, was described as having a "real" resolution of 800 dpi.

    With the release of their 600 dpi optical resolution HD scanners and 1200 dpi optical resolution SD scanners, Contex are now describing their scanners' resolution correctly. However, there are still a lot of older Contex scanners on the market.

    Be aware that the advertised resolution of these older scanners might not be what it seems.

  • Graphtec describe their scanners as having 600 dpi. However, Graphtec scanners only scan at 600 dpi when you scan using their High Quality mode.

    Graphtec Base models do not have a High Quality mode, therefore they cannot scan at 600 dpi.

  • Some large format scanner distributors and resellers describe scanners using their interpolated resolution.

    If you see a scanner described as having "9600 dpi", this is definitely its interpolated resolution and NOT its optical resolution!

    Even a description of "1200 dpi" is likely to mean interpolated resolution as the only scanners with true 1200 dpi optical resolution at present are the new Contex SD scanners.

  • The terms "enhanced resolution" and "extended resolution" are euphemisms for interpolated resolution.

  • The term "maximum resolution" is shorthand for maximum interpolated resolution.

Scan Speed

Scanner manufacturers claim impressive scan speeds for their scanners, but all the manufacturers use different criteria to rate speed and use different conditions to measure it. You cannot compare one quoted speed against another to see which scanner is fastest. In fact, published scan speed figures are fairly meaningless.

First, the lower the resolution a drawing is scanned at, the faster a scanner will go. So Contex and Colortrac measure scan speed at 200 dpi to make their scanners look as fast as possible.

Contex try to disguise the fact that their scan speed is measured at 200 dpi by calling it 400 dpi Turbo. This means that the scanner is scanning at 400 dpi along the width of the drawing and at 200 dpi along its length. After scanning, the 200 dpi is interpolated back to 400 dpi. So, 400 dpi Turbo effectively means 200 dpi.

Second, a scanner can only scan as fast as the PC it is scanning to can receive and process the scanned data. During a scan you will often see a scanner pause as chunks of data are sent to the PC and processed. After the scan is finished, there may be a long wait time before the host PC becomes available again. This means that the speeds that scanners actually scan at can be considerably slower than published speeds.

If you spend extra money buying a fast colour scanner, be aware that it can be as slow as a slow colour scanner for all practical purposes. If the ability to scan in colour at high speed is a requirement then you MUST invest in a high performance PC as well.

The only scanners this does not apply to are Image Access WideTEK scanners, which are fundamentally different to other scanners. WideTEK scanners do all image processing within the scanner itself before sending the scan across the network via a 1Gb ethernet connection. In house speed tests between a WideTEK and "traditional" scanners have indicated that the WideTEK is considerably faster than other scanners, particularly when scanning large colour files. This has recently been confirmed by BERTL, the independent American business equipment research and testing laboratory, who described the WideTEK 36 as the fastest scanner in the world.

Third, if you are scanning delicate drawings, you actually don't want them rattling through the scanner at high speed!

Fourth, workflow. How fast can you work with a fast scanner?

Assuming you can scan at blazing speeds you still have the time-consuming business of unrolling or unfolding your drawings, feeding them into the scanner straight and removing them. Then, if you are concerned about scan quality, you need to check the image after scanning. This means zooming in and out, making sure the full extents of the drawing have been captured, possibly rotating (deskewing) the scan, cleaning it, perhaps scanning it again at a more suitable higher or a lower resolution. All of these activities will slow you down. The time it takes to scan a drawing is only a small part of this process.

Finally, the length of time it takes you to get a good scan will depend heavily on the type of drawings you are scanning and the software you use with the scanner. For example, Colortrac's ScanWorks software includes a feature called adaptive thresholding which helps to rapidly clean dirty black and white drawings. If the threshold setting you've chosen is incorrect, you can change it after the fact using a slider bar. The changes you make can be viewed in real time on the screen. There's no need for experimentation and no need to rescan the drawing. This is a major productivity booster if you are dealing with dirty black and white scans.

Do you really need fast scan speed? It matters most to those with high volumes to scan, like scanning bureaus, but is largely irrelevant to CAD users doing one or several scans at a time.

Despite this, it is one of the major determinants of a scanner's price:

  • The only difference between Colortrac's c (colour) and more expensive e (express colour) models is colour scan speed.

  • The only difference between Contex's HD Base and more expensive HD Plus models is scan speed.

  • The only difference between Contex's SD4430, more expensive SD4450 and yet more expensive SD4490 is scan speed.

  • The only advertised differences between Graphtec's Base and more expensive Pro models are scan speed and interpolated resolution, although the increased speed is achieved by use of a High Speed mode that decreases image quality.

Accuracy

All large format scanners claim accuracies of around 0.1%, and different manufacturers use different conditions to measure accuracy. Even if the scanner is very accurate, the drawing itself may not be, especially if it has been badly treated by folding etc. and has shrunk or stretched in storage.

Note that all scanners are likely to develop accuracy problems and stitching errors over time and if they are moved. CCD scanners in particular should be calibrated from time to time to maintain accuracy.

See Large format scanner accuracy and calibration.

Scan Quality

We believe that all the scanners in our large format scanner comparison chart, with the possible exception of Graphtec Base models, are capable of creating scans of good enough quality for CAD.

Scan quality is the result of a number of factors including the scanner's technology, the quality of its internal components, its optical resolution, the software supplied with it and even the skill and knowledge of the person using it! All scanners are capable of producing poor quality scans if operated carelessly or with inappropriate settings. We have seen thousands of unusable images, often produced by professional scanning bureaus using high end scanners.

For information on how to create a high quality scan, see our article Creating high quality scans for raster to vector conversion.

Before buying a scanner we recommend that you get test scans done of a typical drawing of your own on a variety of scanners. Does the scanner create a clean, sharp image with all the detail you need? Does it produce distinct text characters? Does it keep close parallel lines separate?

Ultimately what matters is that the scan quality is right for the documents you want to scan.

Upgradeability

The advantage of an upgradable scanner is that you can buy the least expensive option now and upgrade to a better specified model later if and when you require it.

Colortrac SmartLF m (monochrome) models are upgradable to colour c or e models. Colortrac SmartLF c (colour) models are upgradeable to e (express colour) models, which have four times faster colour scanning speeds. Colortrac upgrades are supplied via email.

Contex HD Base models can be upgraded to Pro models, which have faster colour scanning speeds. Contex upgrades are supplied as an upgrade card, which is plugged into an external slot in the Base scanner to turn it into a Pro.

We do not suggest that you buy Graphtec Base models because they do not have a High Quality mode. However, Graphtec Base models can be upgraded to Pro models which have a High Quality mode, High Speed mode (allows faster scanning but only with loss of scan quality) and increased interpolated resolution. Graphtec upgrades are supplied as replacement data boards which need to be installed inside the scanner.

If you upgrade to a more expensive scanner because you want faster colour scanning, remember you'll only get faster scanning if your PC is capable of accepting and processing data faster. Don't upgrade on the basis of increased interpolated resolution - all interpolated resolution does is increase the size of a scan without adding to captured drawing detail or improving image sharpness.

Energy Star Compliance

Energy Star is a labelling program designed to identify and promote energy efficient products. At present, only Contex SD, Graphtec and Image Access scanners are Energy Star compliant.

On some literature issued by Contex and their distributors you will see reference to Contex HD scanners as being "Energy Saver compliant". There is no such standard as "Energy Saver" - it is a Contexism.

System Requirements

Make sure that the scanner will work with the PC you intend to run it on. In particular, check the amount of RAM it requires (the more you have the better), the connection it needs (most scanners need USB 2 - USB 1.1 won't work) and make sure it supports your operating system.

All the scanners in our large format scanner comparison chart can be run on Windows but you need to check with individual manufacturers for the versions of Windows that are supported.

If you have an Apple Mac your options are more limited. Colortrac and Graphtec scanners don't support Macs. Contex HD scanners can be run from a Mac but need to be run using Contex's Photoshop plugin or third party software.

The only scanners that are OS independent and that can be run from a Windows PC, Mac or Unix system with equal facility are the Image Access WideTEK range.

Networkability

In our experience, most people assume that their large format scanner will be networkable, allowing it to be shared between all the PCs in an office. In fact, large format scanner networkability is a new development.

The only true network scanners - i.e. scanners that can be connected to a network via ethernet - are Graphtec IS/CS scanners, the Contex HD4230i and the Image Access WideTEK range. Graphtec GB do not promote their scanners' networkability as they say it is slow. This leaves the HD4230i and the WideTEKs.

Scanners4CAD have not timed an HD4230i being used over a network, however speed is definitely not an issue with the WideTEK. The WideTEK contains a powerful internal processor and transmits scans to the receiving PC via a fast 1Gb connection. In house speed tests between a WideTEK and "traditional" scanners have indicated that the WideTEK is considerably faster than other scanners, particularly when scanning large colour files.

Both the HD4230i and the WideTEK contain internal processors. Both can be run directly from a touch screen or touch panel built into the scanner or can be run from a PC connected to the scanner via the network. Both can be run from any standard internet browser.

Contex scanners other than the HD4230i and Colortrac scanners can be made networkable using special software installed on a host PC. Contex scanners are supplied with free software for doing this as standard. Colortrac scanners can be made to network using third party SCP EasyScan software. The disadvantages of using a host PC are that the host PC must be turned on before you can make a scan and will slow up scanning - the scanner will only scan as fast as the host PC can receive and process the scanned data.

Weight and Dimensions

Scanner size and weight are most important if you need a portable scanner or if you work from a cramped office.

The most portable scanner is the Shapemakers Deskan, as it comprises an A4 / A size scan head with guides. If you need a portable sheet-fed scanner, the Graphtec SK200 and CSX300 are the lightest A0 / E size scanners at just 24 and 25 kg respectively.

If you have a cramped office, the smallest A0 / E size scanners are the Image Access WideTEK 36 (43" wide) and the Graphtec SK200 and CSX300 (43.3" wide). The WideTEK is very heavy and will need to be placed on its own floorstand, however the Graphtec scanners are light enough to be placed on a desk or work surface.

Floorstand

Colortrac's Universal Repro Stand
Colortrac's Universal Repro
Stand holds the scanner
above a large format printer


Graphtec CSX300 scanner with paper catch basket
Graphtec CSX300 scanner
with paper catch basket

Do you need a floorstand? How much extra does it cost?

Most buyers opt for a floorstand because it is more practical than placing the scanner on a desk or table top. It minimises the installed footprint of the scanner and lets you easily access the front of the scanner at a convenient height. In addition, many scanners are big and heavy and it would be hard to find a desk or table large and sturdy enough to hold them.

Floorstands come in different varieties. For example, Colortrac offer both a standard floor stand and a floor stand they call their Universal Repro Stand (URS). The URS has a telescopic height adjustment that allows the scanner to be placed above most popular makes of printer, thus saving floor space. Some suppliers now offer similar "single footprint" stands for Contex and Graphtec scanners.

Contex and Graphtec scanner stands include a paper catch basket - a bag or tray attached to the floorstand to catch drawings after they have been scanned. Colortrac charge extra for a paper catch basket, but a paper catch basket isn't strictly necessary, especially if the scanner has the ability to hold a drawing after scanning rather than drop it on the floor.

Most scanners are supplied without floor stands, which are an optional extra. Exceptions include the Image Access WideTEK range and Graphtec scanners (USA only).

Scanning Software

Most of the scanners in our large format scanner comparison chart include TWAIN or WIA drivers. This means that they can be used directly with any software that supports TWAIN or WIA, such as Photoshop and Scan2CAD.

Other than TWAIN/WIA drivers, scanning software functionality is broadly divided into two categories: Scan to file and scan to copy. Scan to file is for scanning to various formats like TIFF, JPG and PDF. Scan to copy is for making the scanner function like a large format photocopier, in conjunction with a printer. Most scan to copy software supports a particular range of printers and may or may not include colour matching so that the colour of the print is the same as the colour of the original scanned document.

Most scanners are supplied with free but basic scan to file and scan to copy software. More comprehensive scan to file and scan to copy software is available for all scanners from the manufacturers or from third party suppliers such as SCP and Paradigm.

If your drawings are generally clean and good quality basic scan to file software will probably do everything you need. However if you are dealing with dirty drawings, the scanning software you use can seriously affect your productivity. With a dirty drawing you will probably need to edit the scan settings several times before you get the best possible scan and you will probably also need tools like adaptive thresholding that are not available in all scanning software.

Useful features to look for in scan software are:

  • Does the software save to the format(s) you want?
  • Is it easy to zoom around the scanned image to quickly check that the scan is OK?
  • Is there a rotate feature so you can quickly rotate a drawing that you've accidentally scanned the wrong way up?
  • Is there an auto paper size facility?

If you are dealing with dirty drawings, additional features to look for are:

  • What scan settings does the software include to help tidy dirty drawings? (e.g. Adaptive thresholding.)
  • When choosing scan settings do you have to guess the correct settings or can you view the effects of changes you make in real time?
  • If you scan a drawing with unsuitable scan settings, do you have to rescan the drawing with new settings or can you change the settings after the fact, without having to rescan?

If you are intending to use the scanner as part of a large format copying system:

  • Make sure the software supports your printer.
  • Does the software support colour matching? (Unlikely to matter in a CAD environment but important in a repro or photo environment where the colour of the print needs to match the colour of the original scanned document.)

It's our opinion that Colortrac's ScanWorks scanning software is far and away the most productive scanning software there is because it only requires a drawing to be scanned once and changes can be made in real time. Both Contex's WIDEimageNET and Graphtec's Scanning Master software require a selected portion of the drawing to be scanned again and again until the scan settings are correct. Once the settings are correct the whole drawing has to be re-scanned with the new settings.

(Note: We believe that Image Access' new Scan2Edit software and Contex's new Nextimage software now work in a similar fashion to Colortrac's ScanWorks software. We will be reviewing these software options shortly.)

However, the best way to see how easy it is to produce a scan with given software is to get a demo of the scanner you're intending to buy. Bring one of your own drawings and see how easily the salesman manages to produce a good scan.

Warranty

Graphtec and HP scanners have the best warranties included with any scanner - one to three years on-site depending on model and location. In the event of a problem you will be visited by an engineer. The warranty includes all non consumable-parts and labour.

All other scanner manufacturers include a one or two year return to base warranty that includes non-consumable parts and labour. This means that while the repair is free, you have to pay to transport the scanner to a place where it can be repaired (usually the manufacturer or distributor's premises) or pay for someone to come to your premises to fix it. In addition, under the terms of a return to base warranty you may be required to return the scanner to base in the original packaging. This means you need to keep and store the scanner's box. Scanner boxes are HUGE.

Most manufacturers offer extended paid-for warranty options. There are two basic types of extended warranty, a swap-out warranty where you get a replacement scanner while yours goes off to be repaired and an on-site warranty - a visit to your premises by an engineer. The advantage of a swap-out warranty is that it usually costs less and lets you get on with scanning while your scanner is being fixed - engineers who visit may not be able to visit next day, and when they do visit they may not be able to fix the problem immediately. The disadvantage of a swap-out warranty is that you still have the hassle of packing and unpacking your scanner and the replacement scanner, and as with a return to factory warranty you may be required to keep the scanner's original box.

In addition to standard warranties, Image Access scanners include a unique diagnostics service. As a networked scanner run via a browser it is possible for outside engineers to interrogate your Image Access scanner directly should anything go wrong.

Disclaimer

Whereas every care has been taken in compiling the information on this page, no legal responsibility can be accepted for any possible errors or omissions. If you discover an error or omission, please contact us and let us know, so we can address the issue. Thank you.