I've been trying to figure out how to create thin, sharp, black lines in illustrator. Every time I make a line either with the pen tool or the line tool it appears opaque or gray. When I make the lines a little thicker they appear to be solid black, but otherwise they look opaque.Take a look at the thin lines on this page http://www.executiveedits.com/ , that is what I'm trying to achieve. This seems so simple, but it's been driving me crazy.
Sharp Edge Objects
In Illustrator you are better off making 1px rules with the Rectangle Tool. Select the tool then click on the artboard so you can enter the precise dimensions.
When AI draws the shape on the artboard it will probably not be in the correct position, viewable in the Info Palette.
*Note: To do this, you will need to use both the Info Palette and the Transform Palette.
If you have a 1pt rule, and you want it to rasterize with crisp edges you need to:
1 - Know that the width of the stroke extends to the sides (or top & bottom) of the point coordinates. Assuming that you have not repositioned the center-point.
2 - Position the rule so the coordinates are exactly in between the area that you intend to cover.
You should make sure to go to File/Doc. Setup and set the Units to Pixels.
Now when you click in the object and look at the coordinates in the Info Palette you can see exactly where it is positioned. If the object was hand-drawn it is not likely to be positioned properly for a crisp raster.
If it's a horizontal rule that is 1px thick (or any odd number), the Y-Coordinate must be at a .5 position, half-way in between a pixel, in a document set to use Pixels as the Unit of Measure.
So, if your 1pt. rule is at Y:480px, use the Transform tool to set the Y-Coordinate to Y:480.5px.
If it's a 2px rule, or any even number, you would set the coordinate to a whole number, like 480px.
Rules That Are Less Than 1px Thick
As for rules that are less that 1px in thickness, generally speaking, a computer monitor can't draw raster information that is less than 1 pixel. So if you are rasterizing a solid black rule that is less than 1px thick, the line will interpret as a shade of grey.
It's almost confusing me to read this, so I can only hope that this helps you. But, it does work.
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