Topic: Plotting Just Linework without White Background

[bmossman]

Is there a way to plot just the linework in cadd to a jpg file without including the white background? I'm trying to overlay the linework onto an aerial w/o the white background....or is there a way in Photoshop to get rid of all of the white background without making the linework fuzzy?

[Guest]

In Photoshop just change the white background to a transparent background.

[Josh Nieman]

Is there a way to plot just the linework in cadd to a jpg file without including the white background? I'm trying to overlay the linework onto an aerial w/o the white background....or is there a way in Photoshop to get rid of all of the white background without making the linework fuzzy?

No, not a JPG.  JPG files do not support transparency, which is what you want.

I'm afraid that no matter what you do you'll get a bit of fuzziness to your linework due to the nature of raster files.

I'm not sure of your whole parameters/situation but...
What if you were to insert this aerial into Autocad, instead, behind your linework, and then printed it all at once to a JPG?  That would be the best bet, imo.

If for any reason this is not an option, what you'd need is a graphics program that can edit the transparency of an image such as the GIMP or Photoshop or something along those lines.  Plot to a regular iamge file (JPG, PNG, etc) then open it in the editor.  Set the transparency color to whatever the background color is, and then the file will be transparent.... if WHITE is the transparent color, then anything white will become transparent.  Then you have to save it as a file type that supports transparency (PNG, GIF, etc)

Of course when you bring this into Autocad, it will fail, now that I think of it.  I don't think transparency comes through in Autocad.

[deegeecees]

I usually make the bg some off color that is not used in layer/entity settings, that way it's easier to select JUST that color in PS.

[Guest]

Whenever I've had to plot to an image file, I've used the PNG PC3 (the JPG PC3 has always produced "blurry" images).  The result has been very good with the PNGs.  You'll probably have to tweak the settings.  And like Josh said, JPGs won't handle transparency... another reason to use PNGs instead.  (Not sure if you can set the transparency in the PC3 or not)

[mjfarrell]

I'm with Josh on this, and wonder why the linework isn't being printed right on top of the image?
If the challenge is the 'solid' hatch the solution is to not use a solid hatch for this particular presentation.

[bmossman]

I'm not sure of your whole parameters/situation but...
What if you were to insert this aerial into Autocad, instead, behind your linework, and then printed it all at once to a JPG?  That would be the best bet, imo.

I initially did exactly what you said, but when I hatched some areas in photoshop the hatching covered up the linework.

Set the transparency color to whatever the background color is, and then the file will be transparent.... if WHITE is the transparent color, then anything white will become transparent.

How is this accomplished in photoshop?

[deegeecees]

I initially did exactly what you said, but when I hatched some areas in photoshop the hatching covered up the linework.

Use a new layer, and set it under the linework.

[mjfarrell]

or use a selection tool, and only paint in the selected areas (marquee)

[bmossman]

I'm with Josh on this, and wonder why the linework isn't being printed right on top of the image?
If the challenge is the 'solid' hatch the solution is to not use a solid hatch for this particular presentation.

I tried hatching in cadd with dots & it bogged my computer down.

I think I just figured a way around the white background in photoshop. Under layer style, blending options, I just blended using the sliders until the white background disappeared and only the linework is displayed. 

[bmossman]

I initially did exactly what you said, but when I hatched some areas in photoshop the hatching covered up the linework.

Use a new layer, and set it under the linework.

The aerial and linework were one image, therefore I couldn't place the hatching above the aerial and below the linework.

[deegeecees]

I initially did exactly what you said, but when I hatched some areas in photoshop the hatching covered up the linework.

Use a new layer, and set it under the linework.

The aerial and linework were one image, therefore I couldn't place the hatching above the aerial and below the linework.

 

Ya lost me on that one.

Going back to re-read posts...

[deegeecees]

What end result are you trying to achieve?

[bmossman]

What end result are you trying to achieve?

My goal is to have a color aerial overlayed with linework and semi-transparent shading as not to completely cover the features of the aerial up.  I think I've accomplished it by doing the following:

- In cadd plot the aerial & linework to a jpg
- Open jpg in photoshop & add transparent shading
- In cadd replot just the linework to a jpg
- In Photoshop import the new linework on top of shading as a new layer.
- Then using blending options to blend out the white background so that just the linework shows.

This seemed to work pretty good...I'll post an image when I'm done.
Thanks for the help!

[Antisthenes]

i didn't read all the posts but i do this allot
just plot to PDF and drag that PDF into PS