While very useful, transparency is not always the best option for certain situations. There are simple alternatives that often provide better printed results…
One common use for transparencies is for drawing shadows on elevations. However, when it comes to printing, there are several points to remember.
The original elements drawn to represent a window.
The shadow is drawn on its own level in 70% transparency.
Once you have your information drawn and you call up Print, you may not see the results you were expecting. The transparent shadow may come out as a solid black fill. Check first that printing is not set to Monochrome but instead is set to Greyscale or True Colour:
Once set to something other than Monochrome you will need to tick the Rasterized box. Without it, transparency does not print.
A preview of the window with “Rasterized” ticked.
Note the subtle shading of the shadow, but also the incorrect line style of the dotted elements
The Rasterized option can cause other issues though:
- Line styles will “render”. This means a dotted or dashed line may appear differently in a rasterised print.
- Line weights may not show up as intended.
- The print itself will be rasterised. While this may not be a problem if you are submitting the print directly to a printer/plotter, the drawing will not be as straightforward to edit if you take it into other packages such as Photoshop or Illustrator.
- Raster files are generally larger than vector files.
As an alternative it may be worthwhile using Override Colours and Element Priority instead.
Using Overrides & Priorities
Change the shadow back to no transparency.
Change the shadow element colour to a suitable shade of grey. If you have drawn all your element ByLevel, you can change the colour in Level Manager.
Set the shadow to a low priority. This will simulate the effect of transparency by ordering the shadow element behind all the other line work.
Open Level Manager and switch the Symbology to “Overrides”. Select all levels and change their symbology to white (colour 0).
Highlight the level where your shadows are drawn and turn off the Symbology Overrides for this level only. This will print the shadow in the shade of grey you selected and keep everything else black & white.
Make sure Style and Weight overrides are off for all levels.
Now when you print you need to make sure Rasterized is off, and you should see more suitable results with shading for the shadows, correct linestyles and weights.