freakyclean
04-13-2002, 05:55 PM
Some sections of this post get pretty complex, if you have any questions please feel free to ask.
This post also deals mainly with problems when using Illustrator files for print purposes, so if you are using the save for web feature or exporting files to non vector formats this post won't apply to you.
That said...
One of the major features of the last 2 versions of Illustrator (9&10) is transparent effects but they can cause several problems.
Problem number one is that postscript doesn't support transparency. This is a problem because that means pdf, eps files and pretty much any printer other than an inkjet cannot take transparency. The transparency has to be flattened in most cases to be used.
Second problem
When Illustrator flattens transparency you can have major problems because it breaks up any images that intersect with a transparent images and applies the transparent effect to them. Invariably at least some vector art is rasterized while some of the same object is left vector. Raster images can be broken up into hundreds of little images if the intersecting transparency is complex.
Warning: even when set to produce only vector artwork when flattening transparency, Illustrator will rasterize it if it's complex.
When a file that uses transparency is flattened this almost always prevents trapping from being able to be done to the file (even automatic in rip trapping).
Also when only part of a vector shape is rasterized then you can almost always tell where the 2 intersect.
The way I around this is:
1. Set up the file the way I want it to appear, and then make a backup.
2. Move any objects above the transparent section or that doesn’t touch it onto their own layer then turn the layer off.
3. Move anything that has transparency onto it's own layer
4. Rasterize what left by flattening transparency, set to 300 - 600 dpi all raster.
5. Export resulting file as tiff
6. Delete the layer for all the stuff you just exported (that's why you made a backup) and show the layer that has the remaining objects on it.
7.Import the tiff file you just made to your illustrator document and place below other objects.
This leaves you with a document that has no transparency but still has the same look.
freakyclean
This post also deals mainly with problems when using Illustrator files for print purposes, so if you are using the save for web feature or exporting files to non vector formats this post won't apply to you.
That said...
One of the major features of the last 2 versions of Illustrator (9&10) is transparent effects but they can cause several problems.
Problem number one is that postscript doesn't support transparency. This is a problem because that means pdf, eps files and pretty much any printer other than an inkjet cannot take transparency. The transparency has to be flattened in most cases to be used.
Second problem
When Illustrator flattens transparency you can have major problems because it breaks up any images that intersect with a transparent images and applies the transparent effect to them. Invariably at least some vector art is rasterized while some of the same object is left vector. Raster images can be broken up into hundreds of little images if the intersecting transparency is complex.
Warning: even when set to produce only vector artwork when flattening transparency, Illustrator will rasterize it if it's complex.
When a file that uses transparency is flattened this almost always prevents trapping from being able to be done to the file (even automatic in rip trapping).
Also when only part of a vector shape is rasterized then you can almost always tell where the 2 intersect.
The way I around this is:
1. Set up the file the way I want it to appear, and then make a backup.
2. Move any objects above the transparent section or that doesn’t touch it onto their own layer then turn the layer off.
3. Move anything that has transparency onto it's own layer
4. Rasterize what left by flattening transparency, set to 300 - 600 dpi all raster.
5. Export resulting file as tiff
6. Delete the layer for all the stuff you just exported (that's why you made a backup) and show the layer that has the remaining objects on it.
7.Import the tiff file you just made to your illustrator document and place below other objects.
This leaves you with a document that has no transparency but still has the same look.
freakyclean