Datasheet

14
c h a p t e r 1: PREPARING DRAWINGS IN CAD OR BIM FOR ENHANCEMENT ■
With the drawing stretched to the maximum size relative to the image size, 1
pixel in the plot equals 0.1924 units (which are inches in imperial units). We must
rationalize this arbitrary measure to the nearest common fraction in order to maintain
graphic scale in Photoshop. In other words, rationalizing in this context means chang-
ing 0.1924 units to 0.25 units. Continue with these steps:
8. Deselect the Fit To Paper check box in the Plot Scale area of the Plot dialog box.
9. Change the unit value from 0.1924 to 0.25. Notice the black-and-white preview
in the Printer/Plotter area shows the crosshatched plot area fitting within the
image size of 3000
×2000 pixels.
At this point, we have found what we are looking for—the numerical relation-
ship between inches and pixels. The rationalized equation is 1 pixel in the image =
0.25 inches in the drawing. If we multiply both sides of the equation by 4, we’ll end up
with whole numbers.
10. Type 4 on the pixel side of the equation and 1 on the unit side. The black-and-
white preview remains unchanged, so the final equation is simply 4 pixels =
1 inch (see Figure 1.17). Press Esc to close the Plot dialog box without plotting.
Figure 1.17 Rationalizing plot scale
Note: If the crosshatched area doesn’t fit within the image size in the preview, you’ve gone the wrong way.
For example, if you rationalized 0.1924 to 0.125 (⁄), you would have gone the wrong way, numerically speaking.
Adjusting 0.1924 to 0.25 (¼) is the correct rationalization in this particular case because the drawing fits within the
image size.
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