Re: Compute the "ideal" image size

It is a bit subjective. But as a general rule over the years I have
found:

* 600 dpi or 1200 dpi - typical listed laser printer resolution

* 300 dpi - historic laser printer resolution - and high enough
resolution to produce high quality text output

* 200 dpi - closer to real-world inkjet resolution and still high enough
to produce readable text

The individual dots of an inkjet printer are relatively large compared to
typical laser printers, so 200 dpi is close the level of individual dots
being distinguished.

End result, I would try for 300 dpi and back down to 200 dpi if the
image/file size is too large. Remember that you can adjust JPG size by
changing the quality as well. Saving at quality 90 or even 80 can often
produce very good looking results while significantly reducing file
size.

Using dpi = dots per inch as that is what I am used to. For your example
of 5cm:

300 dpi @ 5cm = 590 pixels

200 dpi @ 5cm = 394 pixels

If the images are pictures of people or things then 200 dpi is almost
certainly high enough quality. If they contain small-font text (e.g.,
scan of an identification card) then I would try for 300 dpi if
possible.

Manasseh

At 09:49 AM 1/5/2020, Lele Gaifax wrote:

Hi all, and happy new year! When
I produce a PDF with some embedded bitmap image, I always face the
problem of finding a good balance between resulting PDF
"weight" and overall printout quality. In other words, in a
page where I put a particular JPEG image in a square box of 5 cm, what
size (in pixels) should I use for the image without wasting too much disk
space embedding un-resized multi-mega-pixels image as obtained by modern
digital cameras in the PDF? I understand that the answer is conditioned
on the printer technology used to render the PDF on paper and probably
other factors... so, assuming it's some modern-but-common inkjet printer,
what would you suggest as a reasonable relation between a box sized in
"PDF points" and the related JPEG image "pixels"?
Thanks in advance, ciao, lele. -- nickname: Lele Gaifax | Quando vivrò
di quello che ho pensato ieri real: Emanuele Gaifas | comincerò ad aver
paura di chi mi copia. [email protected]
|
-- Fortunato Depero, 1929.
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