By Ashley Calabria, ASLA, LASN associate editor for technology, and assistant professor, University of Georgia, School of Environmental Design

FIGURE 1: These AutoCAD drafts were brought into both Photoshop for rendering and SketchUp for 3D modeling by Birt Garner.

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Technology articles for LASN have recently been covering a variety programs in a tutorial format. The programs selected have been based on their popularity in the field of landscape architecture and suggestions from readers. But the entire series of graphics created for a project rarely stay limited to a single application.

In this month?EUR??,,????'???s article, we?EUR??,,????'???ll discuss some of the most common ways to exchange program information to complete a project primarily using AutoCAD for drafting, Photoshop for rendering, SketchUp for quick 3D modeling and explain different file formats for scanning hand drawn sketches. Keep in mind these are general steps. For more detail on resolution, raster/ vector exchange and other program exchange parameters, consult help menus or manuals.

FIGURE 2: Although you can import Jpeg, Tiff and Bmp files, the .dwg extension is the most interactive, allowing SketchUp to read existing lines from AutoCAD to help create the surfaces needed for quick 3 D modeling. This 3D modeling is by Thomas Brown.

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AutoCAD to Photoshop

AutoCAD 2007 does not currently have a direct saving method for exchanging DWG files into file formats that Photoshop can read. There are two easy ways to address this exchange, both of which should be performed in layout (not model space). One is to go to File ?EUR??,,????'??? Export ?EUR??,,????'??? and select File of type: EPS or Encapsulated Post Script to bring into Photoshop ?EUR??,,????'??? select a location and name to save it. In PhotoShop go to File ?EUR??,,????'??? Open ?EUR??,,????'??? find your file and select open. A Rasterizing Generic EPS format dialog box appears and you can adjust the width, height, resolution and color mode. Depending on the project, I usually select 36?EUR??,,????'?? wide, allow the height to adjust proportionately, adjust a resolution of 300 and select RGB color mode. Checking anti-alias helps smooth the lines in transition from vector to raster format and constrain proportions keeps the width and height linked so the project dimensions don?EUR??,,????'???t get distorted.

Another way to transfer files between AutoCAD and Photoshop is to convert the file to a PDF. The easiest way to work with PDF is to set PDF as the printer in AutoCAD layout or you can go to File ?EUR??,,????'??? Plot ?EUR??,,????'??? select DWG to PDF or Adobe PDF as the printer, set your other plotting parameters and then select Plot and choose a location and name to save it. In Photoshop, go to File ?EUR??,,????'??? Open ?EUR??,,????'??? and select the PDF file. In the dialog box select Crop to Media Box (which keeps the same paper size) ?EUR??,,????'??? Resolution to 300 and color mode to RGB unless you are using other standards. Checking anti-alias keeps the lines smoother and I usually leave the drawing as 8 bit.

FIGURE 3: Views from SketchUp were printed out, hand drawn and scanned back in for sheet layout by Thomas Brown.

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AutoCAD to SketchUp

Although you can import Jpeg, Tiff and Bmp files, using the DWG extension is the most interactive, allowing SketchUp to read existing lines from AutoCAD to help create the surfaces needed for quick 3 D modeling. Keep in mind that Google SketchUp won?EUR??,,????'???t read AutoCAD 2007, so when saving the drawing select AutoCAD 2004 or an earlier version. Also save the DWG file while in model space so that the imported drawing is in real units, not scaled in the layout tab. To open it in SketchUp go to File ?EUR??,,????'??? Import ?EUR??,,????'??? for Files of type select DWG. Once the import results dialog box has finished, you can close it and start tracing your work to create surfaces or insert components. You can check to verify or change the scale of the drawing by using the tape measure across a known distance and checking the value control box. If it doesn?EUR??,,????'???t read the distance correctly, you can type it in at this time and then select to resize the entire model.

FIGURE 4: These AutoCAD drafts were brought into both Photoshop for rendering and SketchUp for 3D modeling by Heath Tucker.

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SketchUp to Photoshop

While working in SketchUp, I usually create the scenes that I plan on printing or using. This allows me to include more detailed materials or components without bogging down the computer. It also helps keep me consistent with my selected views. Zoom, orbit and pan into the view you want to print and then go to File ?EUR??,,????'??? Export ?EUR??,,????'??? 2D graphic ?EUR??,,????'??? select the file of type, most likely either a Tiff or Jpeg. Explanations of each of these file extensions is listed below under scanning. In Photoshop you can go to File ?EUR??,,????'??? Open ?EUR??,,????'??? find the file then hit Open. To adjust the image size and resolution you can go to Image ?EUR??,,????'??? Image Size and make necessary adjustments.

Scanning

The next biggest topic to tackle is the variety of extensions available for saving scanned images. Although I recommend using a resolution of 300 and JPEG format, a brief description of the most commonly used format extensions are listed below.

JPEG: Joint Photographic Experts Group. JPEG is one of the most commonly used extensions because it creates a relatively small file size and it can be imported into other programs such as AutoCAD, SketchUp, Photoshop or InDesign. The only down fall is that it groups very similar colored pixels into a single color, which helps in making such a small file size but causes what is known as lossy compression. It loses the original color sequence of pixels but in most cases this is not noticeable. The problem is when the image is saved repeatedly and each time the image is saved it groups more and more similar colors together. The best way to minimize the affect of lossy compression is to make sure after hitting Save As, that in the jpeg Options Box you set the Quality under Image Options to Max. or 12.

TIFF: Tagged Image File Format. TIFFs are an uncompressed format. The TIFF format is very popular for saving original photos or scans. Because it records the data pixel by pixel, TIFF files don?EUR??,,????'???t lose or group information like JPEGs but they consequently create a huge file size. You might consider scanning or saving your originals as TIFFs but resaving them as JPEGs to work with. That way you always have an excellent quality original to go back to.

GIF: Graphic Interchange Format, BMP: Bit Mapped Graphics and RAW are all considered uncompressed formats and are generally acceptable as extensions for photography and scanning.

PSD: Photoshop Document extension. This is the default Figure 3: Views from SketchUp were printed out, hand drawn and scanned back in for sheet layout. By Thomas Brown.extension when any image has been altered in Photoshop. It allows you to keep your layers, styles, channels and filters in an uncompressed format so you don?EUR??,,????'???t lose any information.

PDF: Portable Document Format or the Adobe Acrobat extension. This is primarily for viewing and e-mailing because saving with this extension creates a relatively small file size.