By Prof. Jose R. Buitrago, University of Georgia College of Environmental Design

Figure 1: AutoCAD elevation printed as a PDF document.

Program interchange is becoming the norm in today?EUR??,,????'???s landscape architecture practice and allows the creation of quick and efficient graphic illustrations. The hybrid images often combine several rendering techniques, including hand and digital graphics, or entirely digital ones with the use of several computer programs. Recently, readers of LASN technology have been introduced to the program interchange between AutoCAD and Adobe Photoshop CS2, thus allowing for the technical drafting of AutoCAD, with the artistic rendering capabilities of Adobe Photoshop CS2. [See LASN?EUR??,,????'???s article ?EUR??,,????'??Adobe Photoshop CS2 and AutoCAD: Rendering Techniques Part I,?EUR??,,????'?? Jan. 2007.] These two softwares are among the most common digital drafting and rendering software found in today?EUR??,,????'???s landscape architecture professional practice and provide a variety of graphic representation styles and presentation methods.

Figure 2: Auto CAD-Photoshop hybrid.

Today?EUR??,,????'???s market provides a vast array of computer generated software capable of creating night view rendering. But investing in one of these night view rendering applications requires the allocation of time and money for purchasing and learning. Depending on the user?EUR??,,????'???s computer rendering capabilities, it might be an option worth investing in, but for the rest of us mortals, an easy and less intrusive form is available with the program interchange of AutoCAD and Adobe Photoshop CS2.

To illustrate this concept, a simple elevation view using Auto CAD, has been created. This view has been printed as a PDF document using Adobe PDF (Adobe Acrobat Professional ?EUR??,,????'??? Portable Document File). Figure 1 is a simple streetscape showing the street, a light pole, sidewalk, planting easement, up lights and dashed lines that delineate the limits of the light coverage.

 

Figure 3: Isolate the area using the rectangular marquee tool before engaging the gradient tool.

The next step is opening the PDF image in Adobe Photoshop CS2. Make sure the paper size and resolution are adequate for final printing and the color mode is set to RGB. Several layers have been created for rendering specific items such as the plant materials, the jogger and car. Figure 2 lists the layers and names created for this example.

The night sky layer was placed on the bottom of the list and the light layer was place under the black line layer. See Figure 2. The layer order is done in this fashion to prevent the black line (PDF image) layer from being covered by the layers that will have rendering on them. Adobe Photoshop users are aware that the order of the layers in the layer palette reads from top to bottom, thus it will follow the same order visually in the drawing depending on the vertical placement in the palette. Since the night sky layer is the ?EUR??,,????'??background?EUR??,,????'?? layer, this layer should be place at the bottom of the list allowing everything else to lie visually on top without being screened.

Figure 4: Customize the gradient tool to create the color scheme that best suits your night view taste.

To create the illusion of a night sky, start by selecting the night sky layer as the active layer. Use the rectangular marquee tool to isolate the extension of the night sky background. Then, using the gradient tool, create a colorful fade out color scheme that best suits your artistic night sky taste. See Figures 3 and 4.

Figure 5: Isolate the limits of the light area using the polygonal lasso tool before engaging the gradient tool.

The next step is to make the Light layer the active layer by selecting it in the layer palette. Then use the Polygonal Lasso Tool, select out an area that follows the extension of the light limits. Again, using and customizing the gradient tool, select a color scheme that is the closest to the light color and that best suits your rendering needs. [See Figures 5 and 6.]

Figure 6: Customize the gradient tool to create the color scheme that best suits your lighting color choice.

After completing your night view rendering, it is a good idea to save two copies of your drawing. One copy is for keeping all the Adobe Photoshop layers intact saved with the PSD extension. The second copy is to flatten all of the layers (to create a simple image before printing) by going to Layer and Flatten Image. This will combine all of your layers into one background layer and help to reduce the file size for printing or e-mailing. Once the image is flattened, you can save the finished image in the format of your choice (jpg, tiff, or pdf). In the event that further revisions are required, the original Photoshop document will enable the user to make further revisions as need it.

Figure 7: Use the opacity layer tool to create the illusion of transparency.

Exploration and trial and error process is the key to master this technique. Figure 8 shows the finished product saved as a PDF format for easy electronic transfer (e-mail) and printer friendliness, as well as a smaller file size (storage capacity) then the Photoshop version.

Figure 8: Use the opacity layer tool to create the illusion of transparency.