It is my goal to share any ideas that will make using Raster Design easier & more productive.

Saturday, October 01, 2005

Reminders & Gotcha's

I thought it would be good to have some notes & reminders of some RD gotcha’s.

Most of my work is with black lines on a white background, but I also like to use this package for photo editing. I like to look for ways to push this program to see what it will do. Most of my tips will be geared toward the black & white, known to RD as bitonal images. Something that can be a gotcha here is the difference in scanners. You can scan a white page with black lines on a color scanner & RD thinks it’s a color image. So what if it only has 2 colors. For basic linework, a monochrome scanner is the way to go. It makes smaller files & is much easier to edit.

Most of my scanning is done at a resolution of 300 dpi. That keeps the images from becoming memory hogs, but still workable. The only time I would recommend the really high resolutions is if you’re scanning small photos for enlargement - like wallet size printed as a poster. Smaller resolution makes it tougher to pick out lines & details.

Speaking of file types & sizes, I’ve gotten questions about the difference between JPG & TIF files, as well as others. My main experience is narrowed to these two. Which is the best format for RD? JPG’s are smaller & easier to store. Great for full color maps & things that don’t need to be edited. If you need to make changes to the files, TIF’s are easier to work with, but file size is quite a bit larger.

In Vanilla AutoCAD, you can insert images, scale, rotate & print them, but edits are not an option.

Keep in mind that the raster images are treated like an XREF with AutoCAD. When I started working with RD, that was the hardest part for me to grasp. If you e-mail or copy a DWG file with an image, there are 2 separate files to deal with. We did have an express tool called pack & go. Now, we have e-transmit in the file pulldown. E-transmit neatly packs all necessary files into a little package that can be transferred in most any form you might encounter.

Many AutoCAD commands work in RD, as well after parts of the image have been selected. Some of them are Move, Copy, Rotate, & Erase. More are available, but you will see them as you work with the program.

If you want to do anything to the whole image, the Imageframe must be turned on. AutoCAD has added a new setting for Imageframe. In the past, it was either off, meaning no selection, or on, meaning it showed in prints. Now, there is a blend of the two. If you set Imageframe to 2, it is in the on setting, but doesn’t plot.

If you insert an image into a drawing just to edit the image, don’t forget to save the image. Something new to RD2006 is the failure to ask if you want to save the image when you close, unless you save the DWG file. Some of the images I work with don’t have a DWG file tied to them, so it is very possible that I work on an image, print it, or whatever, then tell RD to erase the file & go to the next one for more of the same. If I didn’t save the image file, my clean-up work just got dumped. Hopefully that will be tweaked in the next version & I’ll get my save reminders back.

2 Comments:

Blogger RobiNZ said...

have you considered PNG?

To quote wikipedia
http://en.wikipedia.org/wiki/Png

PNG was not intended to replace the other popular web image format JPEG. JPEG will produce a smaller file than PNG for photographic images since it uses a lossy encoding method specifically designed for photographic image data. PNG is a better choice than JPEG for storing images that contain text, line art, or other highly-contrasting images, as well as for images that are likely to undergo further editing as JPEG suffers from generation loss issues.

4:16 AM

 
Anonymous Anonymous said...

Have you noticed that when a portion of a TIF image is copied and then merged back into the original image that it will grow by several pixels and will also shift down and to the right if you are using RD2005?

3:00 PM

 

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