NewDeal Hot Tip 1202

[Hot Tips for...] NewDraw

NewDraw Bitmap Tips

I have two scanners. One saves its files as PCX format in 100, 200, 300 or 400 dpi. The other creates TIF files in 200 dpi only. The PCX bitmaps give me no trouble at all when cropping in NewDraw with the Bitmap Select tool. I can cut or copy a section and it is identical to the original when viewed at 400%.

The TIFs gave me trouble until I learned how to handle them. After import, if I use the bitmap tools on them, they will "explode." So, now I select them with the regular pointer, go to Attributes, Bitmap Format and fix them by setting them to 200 dpi.

I know they are 200 dpi, because the scanner program told me. However, Bitmap Format in NewDraw shows them as 72 dpi. All I do is set the dpi to 200 and click Apply. Then I can successfully copy, cut, or crop with no problem. To show that the bitmap retains its high-res dpi, use Transform, Convert, Convert to Bitmap on a copy. Notice that Bitmap Format jumps from Custom dpi to plain old 72 dpi. Also, if you do it in 400% View, you can actually watch the image get coarser.

If you want to use Custom dpi to make your bitmap a higher resolution, keep in mind that it's only useful if you're going to edit, pixel by pixel. The image will remain the same, only each pixel in the original will now be made up of more than one pixel.

Export at the DPI you want

By default, NewDraw exports at 72 dpi only. You can effectively change that by rescaling your graphic. For precise control, do it with the custom scale option in NewDraw. Simply Group all the objects in your document (text, vector, bitmaps, everything) and scale it to the proper size that will give you what you need when translated to 72 dpi. Make sure your grouped object is selected and choose Export Selected Objects from the Export dialog box.

The calculations for achieving the desired dpi aren't difficult. The table below lists the most common desired resolutions for bitmaps

Desired DPI
Scale Percentage
360
500%
300
418%
240
333%
200
278%
150 (medium resolution on a laser printer)
208%
120 (medium resolution on a dot matrix printer)
167%
100 (low resolution fax)
139%

Converting Black and White Bitmaps to Color

To prepare black and white bitmaps for color work, it is necessary to first convert them to 16 color. Select the bitmap with the Pointer tool , then choose Attributes, Bitmap Format, 16 Color. Click on OK. Remember to also set the proper dpi in the Bitmap Format dialog box. The default is 72dpi. If the 72 dpi button is selected, you're OK. But if your bitmap is say, 100 dpi, then the Custom dpi button will be selected, but 72 is still in the window and will need to be changed to 100.

Converting black and white bitmaps to color will also allow you to make them transparent.

Next, select the bitmap with the bitmap Frame tool . Finally, select the bitmap tool you want to use , then the color or other attribute, and apply to the bitmap.

A bonus feature is that while in bitmap editing mode, each tool you use "remembers" the color last applied to it. So if you selected to use the paint can with yellow, then go to the bitmap rectangle tool with blue, and then go back to the paintcan, the paint can will still apply yellow. Go back to the rectangle tool and it will apply blue. Whenever you want to change colors, select the tool and then select a color.

The most common errors in using the bitmap tools seem to be:

  1. Forgetting to convert black/white bitmaps to 16 color
  2. Applying a bitmap tool to an unselected (with the Frame tool ) bitmap. When you do this, you get the default color black.

Another way to color bitmaps is by using the object tools to draw color overlays.

  1. Draw a colored rectangle over your black and white bitmap.
  2. While the rectangle is selected, choose Attributes, Area Attributes, Draw Mode: OR.
  3. Draw Mode attributes do not always print WYSIWYG unless the object containing Draw Mode attributes is first converted to a bitmap, so: Select both the rectangle and the bitmap and Transform, Convert, Convert to Bitmap.
When you do this, you will end up with 72dpi. For higher resolution, simply group and scale the elements up before converting to bitmap and then scale back down.

Some customers prefer using the object tools for coloring because there are more tools. There are no polyline bitmap tools and the outline of rectangles and ellipses is not available. For color fills, draw the color shape needed using the object Spline tool to trace portions of a bitmap. There is no worry about plugging holes or isolating the area to be filled. This is a nifty technique. The Spline tool is the last object tool, the one that's shaped like a U. To use it, just click, hold and drag, click, hold and drag, tracing the part of the graphic on which you want to overlay color. End the trace at the same point you started to create a filled object, select 50% fill and if you want, change the color. You don't have to change the graphic to 16 color to use this technique.


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Last Modified 2 Mar 1999