NEWB question on DPI

[Mike vonBuelow]

Where is this specified in Corel ? When I first open a new file? And can it be adjusted in the print options once that window opens up?

(I'm at work so I cant go searching at the moment, and I want to ask while I still remember)

[Larry Bratton]

Corel Draw does not specify per se. I believe there is an option to specify at what dpi vectors are saved though. Your dpi for bitmap images is based on how they are created. Vectors are not dependent on dpi for good quality output. If you are rastering a bitmap, the settings in the driver should match the resolution (dpi) of the graphic

Here is a link to some info on dpi http://www.epinions.com/content_1883086980

Correction: I was thinking of Rendering Resolution setting which is applicable to applicable to drop shadows and interactive transparencies.

[Ed Bagley]

Mike, If you just want to know the DPI of a opened file in CDR....Click on file the click on Document Properties. All the info about that file will be there, If you want to change the DPI you will have to go into Photo Paint

[Larry Bratton]

Mike, If you just want to know the DPI of a opened file in CDR....Click on file the click on Document Properties. All the info about that file will be there, If you want to change the DPI you will have to go into Photo Paint
you can only change the dpi of a bitmap in Photopaint. Changing the resolution in a graphics program will not improve or change the quality of the bitmap. Corel Photopaint allows for re-sampling but the quality is still dependent upon the original resolution.

[Mike Null]

Under tools, options, customization, workspace, document, page you will find a box which allows you to choose the dpi.

[Larry Bratton]

Under tools, options, customization, workspace, document, page you will find a box which allows you to choose the dpi.
Why would one want to render a Corel Draw Page any higher than 300dpi?
(I suppose rendering at say 72dpi would allow for online webpage publication.)

[Mike vonBuelow]

Why would one want to render a Corel Draw Page any higher than 300dpi?


That's a great follow up question - under what circumstances would I?? If any?

[Mike Null]

Larry

300 dpi is the max option you have. It goes down to 72 dpi.

[Doug Griffith]

Why would one want to render a Corel Draw Page any higher than 300dpi?
For placing the graphic in a DTP application such as Quark or InDesign and outputting to a high line-screen. Or, needing to place the graphic at a physical size that is beyond the capability of the software. For example needing to output the size of a bus and the software only goes to 4' x 4'. for that, you scale the art down and increase the resolution relative to the upsizing during output.


Changing the resolution in a graphics program will not improve or change the quality of the bitmap. Corel Photopaint allows for re-sampling but the quality is still dependent upon the original resolution.
It won't improve it but will affect quality and processing time depending on where the re-sampling takes place (bitmap software, DTP software, software RIP, harware RIP), and what type of re-sampling is performed (ie. bicubic, bilinear). If performed in a bitmap app, there is also the option to perform further actions on the image such as sharpening.

[Richard Rumancik]

Where is this [dpi] specified in Corel ? When I first open a new file? And can it be adjusted in the print options once that window opens up? . . .

Mike, I have a hunch that the responses you have got really aren't applicable to what you are trying to find out. Maybe I'm wrong . . .

CorelDraw is a vector program; however, it can import bitmaps and also edit bitmaps by launching PhotoPaint. The Rendering resolution is used (as Larry noted) to create some special effects but chances are you were asking for another reason.

Basically, your laser will take your CorelDraw file and sort it into vectors and raster entities. The vectors will be cut or scribed lines, whereas filled shapes and text will be rastered. Most lasers know which lines are vectors due to a convention generally adopted by laser system manufacturers: thin lines (let's say smaller than .003" wide) are vector lines. Lines above .003" will be assumed raster lines.

So if you have some filled shapes and some text in your drawing, there is no dpi set at all within Coreldraw. (Ignore the shadows for now.) It is only set when you try to output it to the laser. In the driver, you can decide at which resolution you would like it to "print".

However, if you have imported a bitmap into your CorelDraw file, it will have an inherent dpi associated with it based on when/how it was created. If it was a 300 dpi graphic then it would look best lasered at 300 (or sometimes 600, or 150) but will probably laser poorly at some non-multiple resolution eg 250 dpi. So dpi is selected at the printing stage, but for some graphics it is pre-determined what resolution you should be using for the laser, by virtue of the properties of the embedded bitmap.

I suppose if you were lasering text with shadows, you would probably want to set the CorelDraw rendering resolution to 300 and then output to the laser at 300. But I have never tried this.

If your question was related to something else please clarify.

[Mike Null]

I think Richard and Doug are on target based on this.

[Mike vonBuelow]

I'm still trying to figure the basics out, so when the issue of crosshatching came up and DPI was addressed, I went down this path (pun intended) with this post.

And Corel is new to me, as I've always used PS and AI for my graphic needs.