Export annoyance

CorelDRAW users often get caught with unexpected results when exporting to bitmaps.

How? In the diagram below, C has nothing to do with A or B.

But, if you change C, A and B will change on you.



What should you do if you want certain pixel dimensions AND a DPI value? Just set the DPI value FIRST.

Let's have a chat about DPI...

You ask, "Jeff, isn't DPI really, really important?"

I say: "It depends".

A . Scanning: YES. I always scan at the optical resolution of my scanners which are 600 DPI. This ensures you're getting your money's worth from your scanner. It gives you the most pixels to work with for cleaning up the scan.

Consider what you're scanning, though. If you're scanning film, you could go higher. Scanning newsprint at higher resolutions wouldn't make much sense, since the material you're scanning from is so rough in the first place.

The DPI chosen for scanning has nothing to do with the DPI value we saw above in the export dialog.

B. When you set the DPI value above, that value is put into the file if the format supports DPI. Having the value in there only does 2 things:

1. Provides details to a printing device how much to compress the pixels into a physical output area, such as 300 pixels per inch.
2. Gives CorelDRAW information on how to auto-scale an image imported into the document.
   

Summary: if for some reason you need a final DPI value for bitmap export, choose it first. Then change the pixel dimensions.

Never ever forget that "Pixels are the Gold", not a file's current DPI value.

Sometimes I ask students: "What's a better file to use?"

image A: 1200px X 1200px @ 72 DPI
image B: 1200px X 1200px @ 300 DPI
image C: 1200px X 1200px @ 600 DPI

They're the same.... Pixels are the Gold.

Note that the GIF format doesn't support an embedded DPI value in the file.