Johannes,

I am sorry if I sounded a bit harsh.  My bad!
I should have qualified which information was incorrect.

In one paragraph, you wrote:

"It is quite simple:
 If you have an image of 600x600 pixels and print it with 600dpi, then it
 will be 1x1 inch large. If you print the same image with 300dpi you get a
 2x2 inches image etc."

This is sort of correct.  Yes, you certainly could print the 600dpi image at
1"x1".  You could also get the same or better quality print from the same 600dpi
image at 2"x2" or even 4"x4" on some inkjet printers.  "Dots per inch" and
"pixels per inch" are two entirely different things.  One has to do with
printing, and the other has to do with video display.

In your example - if the 600x600 image was saved as a tiff at 600 pixels per
inch in any commercial image editor (i.e. Photoshop or CorelPaint), The image
will most certainly be printed 1x1 inch from within that program.  Unless of
course, your printer allows you to print at a different enlargment.  If that
same image is placed in Illustrator or Freehand or someother graphic
application, you have the ability to change the size of the image.  The number
of available pixels doesn't change, but the effective dpi does.  The same 1"
square 600x600 image enlarged to 2"x2" will now have an effective dpi of 300.

One thing I did mention in my original response was this - all the information
that I provided can be found in any 3rd party book about Photoshop or Computer
Imaging for press.

Again, I am sorry if I bit down too hard.

Sincerely,

Tony Vigil
Carta.graffiti


Johannes Hubert wrote:

> Tony Vigil wrote in message <354AD5A1.4F0BBE00@gte.net>...
> >Actually, all who replied had the entire thing all wrong.  Sorry - but
> true!
>
> I always like these "You are all wrong!" replies :-)
>
> >I say this from more than 10 years of experience with computer programs
>
> What, only 10 years? You surely did start late, did you? (Help, don't flame
> me, that was supposed to be a joke!)
>
> Actually, everything you write in your mail after that is possibly very
> correct and I am not going to dispute it, but:
> Nothing what you write proves anything of my stuff wrong, so I don't
> understand your first line "everything is wrong".
>
> What you say is essentially, that you don't need to use the full DPI the
> printer is capable of, to still get the fullest quality. Nothing against
> that, it might be true. But the theory is still: If you want to print with X
> DPI and your image is to be Y inces in size, then you need to create a
> source-image with X*Y pixels. And it was that "theory" that I explained in
> my post, because of the very common misconception about images "having" a
> DPI value.
>
> And to this you added the valuable advice that, while theory says you need
> X*Y pixels, in real life (X*Y)/2 are still enough to get full quality.
> Very well, only please don't say anything like "all who replied had the
> entire thing all wrong" without backing that up - and you definitely didn't!
>
> Johannes.

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