Hardware

New 36 Scanner Offers Great CAD Options

25 Oct, 2006 By: Henrik Vestermark

GTCO Calcomp's ScanPlus 6 LF736 large-format model provides direct integration with AutoCAD


The second half of 2006 will prove to be an interesting time for wide-format scanner users. During this time, it's expected that all of the major scanner manufacturers will release new and enhanced models that will dramatically change the scanner market.

On August 1, GTCO Calcomp revealed its new line of scanners that added impressive scanning features. The new models range in size from 25" wide to the top-of-the-line 54" ScanPlus 6 LF954 scanner. All new models share the same hardware platform (except the 25" model), making them virtually identical in regard to scanning quality and available features.

In this article, I'll offer a brief overview of the new line, then focus on the GTCO Calcomp ScanPlus 6 LF736, a great choice for CAD users. With this model, the company is offering software including a free plugin called WIDEcapture that enables users to directly scan drawings into AutoCAD instead of scanning to file and then importing the file.

GTCO CALCOMP: New Scanners at a Glance
  MSRP (includes WIDEimageNET plus two years' on-site service in U.S.) Speed: Black-and-white (ips) Speed: Color (ips) Resolution (dpi)
36" scanners
LF436 $10,900 10 1.5-3* 200
LF736 $12,900 12 0.6-1* 600
LF936 $16,900 12 1.5-3* 600
42" scanners
LF542 $10,900 6-12* N/A 600
LF742 $14,900 12 0.6-1* 600
LF942 $20,900 12 1.5-3* 600
54" scanners
LF954 $27,900 12 1.5-3* 600
 * denotes the Plus model (additional $2,000)

The most popular scanner width for CAD users is 36", although most scanner vendors now offer comparable 42" models that are only slightly more expensive. At the end of the day, CAD users continue to choose 36" scanners because their archival drawings are usually that size and a savings of $2,000 for the smaller size simply can't be ignored.

GTCO Calcomp offers three 36" scanner models to choose from. The least expensive is the LF436 ($10,900), with scanning speeds of 10ips in black-and-white and a fast 1.5ips in color. Its only limitation is the 200dpi optical resolution that might not be acceptable for all CAD departments. The next in line is the LF736 ($12,900), a 12ips black-and-white scanner offering moderate color speed of 0.6ips. The top-of-the-line is the LF936 ($16,900), with a maximum speed of 12ips in black-and-white and 1.5ips in color. I'll focus on the LF736 because it offers excellent performance at a moderate price, a perfect compromise for most CAD applications.

The GTCO Calcomp series of scanners comes standard with two years' on-site service warranty for U.S. customers. Outside the United States, the warranty covers parts only for two years.

GTCO Calcomp LF736: Getting Set Up
The LF736 scanner arrives in two cardboard crates holding the scanner and the optional scanner stand ($890). The scanner stand is easy to assemble even if you're alone on the job. Assembly instructions are easy to understand. The hardest part of the assembly process is placing the scanner on the stand. To lift the 126lb unit and secure it on the stand, you'll want to have two people.

Standard Software Installation. Each new GTCO Calcomp scanner comes with three software programs. First, install WIDEsystemNET, which installs the USB and FireWire drivers. Then, install the scanner maintenance application for scanner calibration, and finally WIDEimageNET, a state-of-the-art scan-to-file application.

The WIDEimageNET installation requires a key code that you should keep in a secure place as you'll need it to upgrade or reinstall the software. GTCO Calcomp has a liberal upgrade policy that lets you download scanner software upgrades free of charge on its Web site.

During installation, choose your correct language from the nine supported, including English, Spanish, German, French, Dutch, Italian, Japanese, Korean and simplified Chinese.

Scanner Calibration. For optimal scans, you must calibrate your new scanner before use. GTCO Calcomp supplies scanner calibration software and a calibration sheet that automates the process. The automatic calibration process ensures that all three motorized cameras are aligned correctly. The next step calibrates the black-and-white points and does camera-to-camera calibration to ensure that the graytone levels are identical for each camera, eliminating the graytone shift that can occur between cameras. The final step is a color calibration using the ANSI.IT8 color calibration chart to ensure accurate color matching. The whole process runs in about 12 minutes.

Scanner Software. As mentioned earlier, each scanner comes with bundled software, including the WIDEimageNET scan-to-file application and a 30-day free trial version of the scan-to-print software, JETimageNET, with its own built-in RIP software that supports the most popular wide-format printers. You can buy a full license of JETimageNET for $1,990.

Additionally, the free-to-download GTCO Calcomp WIDEcapture plugin lets you scan drawings directly into AutoCAD. I tested the LF736 scanner using trial versions of AutoCAD and Autodesk Raster Design CAD software.

Once you've installed all software, including WIDEimageNET, a couple more steps are left to activate WIDEcapture in AutoCAD and start the scanning process. Instructions are well documented and easy to follow.

The WIDEcapture plugin adds fast AutoCAD integration to your scanning operations and makes it easier to manipulate your scans. To begin scanning from within AutoCAD, select Insert and click on Scanned Raster Image to activate the Scanning dialog box.

figure
AutoCAD's Scanning dialog box.

The WIDEcapture plugin is a traditional scan-to-file operation. It supports a variety of different file formats, including JPEG, RLC, TIFF, PCX, BMP and CALS. The software processes 30 different black-and-white file formats, 10 grayscale formats and nine color formats, adding to what AutoCAD supports. Be sure to choose a scanning format supported by AutoCAD. If you have questions, refer to AutoCAD's Help menu.

AutoCAD Scanning. When scanning to AutoCAD, set up basic scan parameters prior to scanning:

  • Scanning mode, such as color, grayscale or black-and-white
  • Scanning resolution in dpi
  • Drawing size
The software even offers a preset list that gives you default scanning parameters for various types of engineering drawings and maps, such as blueprint, brown/sepia and maps. While scanning or in preview mode in black-and-white, you can adjust scan parameters such as fixed threshold, sharpening or despeckling a hole-filling. In color, you can adjust Gamma corrections, sharpening, softening and blurring, making it easy to set optimal scan parameters.

figure
While scanning or when in Preview mode, you can make adjustments to your scan.

One of the nice features of the WIDEcapture plugin is the availability of cropping, rotating and alignment at scan time. Instead of loading the whole image file, in prescan mode you can crop the image and reduce the size and data amount transferred into the AutoCAD, saving time.

When the scan is complete, exit the dialog box and the raster image is automatically loaded into AutoCAD. The raster image is the same as if you had manually imported it into AutoCAD. From that point, you can use Autodesk Raster Design to continue to manipulate the image. The picture below shows AutoCAD with the Raster Design options installed.

Raster Design has some nice features for manipulating the raster image data, but we'll save that for another article.

figure
After scanning this image into AutoCAD, we used Autodesk Raster Design to make changes.

Scanning Difficult Drawings
The WIDEcapture plugin for AutoCAD has an advanced feature called Adaptive Threshold for cleaning up deteriorated drawings and blueprints. Deterioration can be a result of too many years sitting in a drawer, exposure to light or blue background noise on a blueprint. You select Adaptive Threshold as one of the black-and-white scanning modes.

figure
Here's an example of WIDEcapture's Adaptive Threshold at work. The original is on the left and the cleaned-up version is on the right.

If you are going to vectorize or perform raster editing on the drawing, using Adaptive Threshold is a must.

Quality Improvement Features
The GTCO Calcomp LF736 scanner has two unique features to help you obtain higher quality scans: anti-alias and high-quality scan mode.

Anti-alias is a high-quality resampling of the scanner's optical resolution. Scanning is performed at the scanner's optical resolution, and resampling to the requested resolution is done in WIDEimageNET. Although it slows the scanning process, it's effective in cases where scanning raster originals leads to moiré-like interferences in the scanned image -- those wavy patterns that can appear across the pictures.

In high-quality scan mode, the scanner increases the camera exposure time to allow more time to capture the light and in turn obtain a higher-quality image. It improves quality of color and black-and-white at the expense of scanning speed -- the scans usually take eight times longer. This option is useful for difficult originals that normally would produce a high degree of noise.

The Scanner for CAD
In my opinion, the GTCO Calcomp ScanPlus 6 LF736 represents the best value for your money when evaluating this new scanner line for CAD applications. Its combination of midrange pricing, 36" scanning capability and fast black-and-white and moderate color scanning speed makes this scanner a recommended choice for the CAD community. If you can use a 36" scanner with less optical resolution, then go with the LF436 and save $2,000. Or, if color scanning is not on your list of requirements but you need higher optical resolution quality than the LF436 can deliver, go with the LF542 monochromatic scanner and pay $2,000 less. You can use the free AutoCAD WIDEcapture plugin with any of these scanners.


AutoCAD Tips!

Lynn Allen

Autodesk Technical Evangelist Lynn Allen guides you through a different AutoCAD feature in every edition of her popular "Circles and Lines" tutorial series. For even more AutoCAD how-to, check out Lynn's quick tips in the Cadalyst Video Gallery. Subscribe to Cadalyst's free Tips & Tools Weekly e-newsletter and we'll notify you every time a new video tip is published. All exclusively from Cadalyst!
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