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Using large format scanners in engineering companies

This page is provided in order to assist vendors and customers for large format scanners (also known as wide format scanners) to answer questions that are frequently asked in engineering companies.

The diagram below shows where Trix software is used to complement large format scanner installations. (You can download an Acrobat PDF copy of this graphic by clicking on the image below or on Large Format Scanner Diagram PDF.)

Questions often asked about wide format scanning by engineering users:

On how to edit scans in CAD:
Will I be able to scan directly to DWG or other CAD format?
When I scan directly into DWF or PDF, why don't I get vectors?
So how can I get vectors from your scanner?
Does TracTrix have to be on the computer that drives the scanner?
What scanner settings should be used if I want to convert the scan to CAD vectors?
How long will it take me to learn to do raster to vector conversion?
If I use TracTrix, who will support me if I have problems creating CAD vectors?

On how to synchronize CAD files with the formats produced by the scanner:
How can I convert my CAD files to the same formats that are coming out of the scanner?
How can I view and plot scans of engineering drawings?

Comparing scanners before purchase:
As a customer, what should I ask the vendor before I order?
 

No. Scanners produce raster images. These represent images as, basically, rows of dots stored in a file in a format such as TIFF or BMP.  CAD applications store images very differently. They store mathematical descriptions of lines. These are known as vectors.
 

Although DWF and PDF formats are primarily used for storing vectors they can also store raster images. And as scanners produce only raster images the DWFs and PDFs they create contain only the raster content. This still has to be vectorized before it can be edited in CAD.
 

You can use a 'raster to vector' conversion software such as TracTrix to convert the dots in the raster image to the vectors you need in CAD. TracTrix can save vectors as DWG, DXF, IGES, EPS or HPGL formats. See more on raster to vector here.
 

It's your choice. TracTrix can be installed on any computer that has access to the raster files that the scanner produces. So it can be on the scanner computer, the computer with the CAD application or an entirely separate computer.
 

Assuming you are starting from a print of a single color engineering drawing the scanner should be set to scan to monochrome - that means a pure black and white image. Set the resolution to 300 dpi. This is normally perfectly adequate to capture the detail from most engineering drawings. It's also very important to switch off the dithering function so that the solid lines on the original print are captured as solid lines in the raster image.

DEMO NOTE FOR LARGE FORMAT SCANNER VENDORS: Before demoing your scanning system in conjunction with TracTrix be sure to check with your technical support for the required scanner settings. We know of scanner sales that were lost because this important detail was overlooked.
 

It only takes a couple of minutes to learn the basic process. The full tutorial, so you can learn how to adjust settings for the best vector results, takes about half an hour.
 

Trix Systems, the developers of TracTrix, include 90 days full support by telephone and email. Their support staff includes engineers who are familiar with both the software and the practical engineering applications to which it is applied.
 

How can I convert my CAD files to the same raster formats that are coming out of the scanner?
 
You don't need to plot out a print and then scan it a raster file. TracTrix can open DWG, DXF and HPGL files and convert them, one at a time, to raster formats or Acrobat PDF. You can control the size and clarity of the new image, adjust line weights and switch on and off layers.

If you have higher volumes to convert use Trix RasterServer. This is a server strength software. Only one license is needed to serve an entire site.
 

As a customer, what should I ask the vendor before I order?

Wide format scanners cost many thousands of dollars. You should expect to have a sales person available to you to answer your questions and provide you with sample scans. Here are 3 key requests to make: 

• Let me see the manuals you'll be providing. You should expect to be provided with manual(s) that are simple to use yet comprehensive. The time to find this out is before you buy.
   
• Show me that the scanner can be configured so that raster images are saved with solid lines, just like my original. Many scanners default to saving 'dithered' and 'anti-aliased' lines. These are very pretty to the eye. On close inspection however you will see that the the lines are not solid but a mix of black and white pixels. You'll get much better vectors in CAD if your scans are solid black lines. And good viewing software will anti-alias the raster image for you anyway.
   
• Demonstrate that I can rapidly preview the raster image during the scanning process. It can take take quite a while to scan a large sheet. So it's very frustrating to have to wait until a scan is complete to find if it has the legibility required. Real-time zoom in on the raster image will enable you to check that the fine detail is both clear and that thin or faint lines are being captured.