"Have a line drawing, some what detailed that I did by hand and scanned into computer. Now I want to apply color (flat areas) in Illustrator. I need to give the line art drawing a path and I want the path to be exact. This is my problem. Using autotrace in Illustrator or doing a conversion in Streamline, the line work is not exact. It looks kind of pixelated, doesn't carry the quality of the hand drawing. I know this can be done. I just don't know how to do it."

I have used Streamline in the past. The reason I don't anymore is because I've found a much better and more exact method.

In Photoshop, select the area in the illustration you want traced (if you want the entire line drawing done, you might use "Select/Color" and select the black area, which should give you the "marching ants" outline around the black areas in your image). Then go to the Paths pallette and make a path. I usually tell it to follow within 1 pixel. This will give you a pixellated path but it will be an exact copy of what is in your illustration instead of rounding the image off as Streamline, Illustrator and FreeHand do.

Once the path is made, Edit/Copy and go into your Illustrator (works with FreeHand too) document and Paste. The entire path you made in Photoshop will be pasted in your document (with no fills or strokes - you will have to do that). Depending on how complex the image is, you may be able to join the paths (I think Illustrator calls it making Compound Paths). If it is too complex for this, go into Keyline mode (I don't remember what Illustrator calls this -- not the preview mode) and select areas you want black (or whatever) and colourize them. There will be a lot of points on each line as it follows each pixel that was in the original bitmap version, but they will be exactly where the scanned image was. (Also, you can experiment with the "Simplify" plug-in in Illustrator to get rid of some of the redundant points) Hope that helps.


The quality of your Streamlined image will be determined by the quality of the bitmapped file you start with. For line art conversions, I usually scan my line art at anywhere from 300-1200dpi depending on the look I'm aiming for.

Then there are a variety of controls within Streamline that you can use to tighten, loosen, etc. the conversion. It will take some experimentation but it can be very exact if you want it too. And if you start with a good TIFF or PICT.

- -kevan

Photoshop would work out well for you, as would painter. It's illustrator that wouldn't. Illustrator is vector based, which means that anything you draw is represented by a mathmatical formula. When you create a scan, it's bitmap based, which means the image is defined by code representing color one pixel at a time. If you're using illustrator, you'd have to convert the bitmap image to vector for the program to read the image and to really work with it. (You could just apply color without much relation to the scanned image, but I didn't get the feeling that's what you want.

Date: Thu, 11 Feb 1999 12:51:11 -0800
From: stephanie anne holland
Subject: Re: illustration: Illustrator 8.0

Anyhow, in a jam, there's a pretty good illy listserve. It's not fun like this one but it's a good place to go for "how to" questions--couple of 'em have written books!

All the best,

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