change/compress picture resolution to 600 dpi?

[ker_01]

PowerPoint 2003 on WinXP

I did google before posting, and found lots of hits on exporting powerpoint
as an image, the descriptions of the built-in picture compression
options,...but not what I'm looking for.

I have two powerpoints with some pre-cropped high-resolution pictures. Total
filesize is about 50MB, the other is 75MB.

I want to use [format picture/ picture/compress] to reduce my filesize if
possible. However, the presentation is designed for printed use (not an
on-screen presentation), and the pictures need to be extremely clear when
printed (resolution matching the printer's 600dpi output).

Is there a registry setting where I can change the compress setting from
200dpi up to 600dpi? I don't care if the dialogue box changes, as long as
the resolution isn't pushed below 600.

I'd rather stay with huge files than have lower than 600dpi resolution, so
if there isn't a solution, I'll still be ok unless the printer chokes on
such a large file (maybe requiring printing a page or two at a time).

Thank you!
Keith

 

[ker_01]

Hi Steve!

I am working with color images; I'm using a networked color laser printer
that is at least 600dpi (it may be 1200, but I'm not positive). I assume the
difference between 600 and 1200 would be beyond the scope of human
detection. I'd think (just a guess, I haven't tested) that the difference
between 100-200 is more easily detectable, and the difference between
200-300 detectable under certain circumstances, etc.

I hadn't thought about it, but the color laser probably must also use
interpolated dots to provide the appearance of the color range- so the more
color, the lower the 'true' resolution would be anyway. I can't help but
wonder if a 100dpi color image on a 300dpi printer is rendered in a way to
use the extra pixels for the coloring- probably not, it probably just prints
larger blocks of interpolated color... man, now I'm going to be wondering
about that all weekend. I suppose a color inkjet could overprint (resulting
in dye mixing for color rendering), but that's a whole different animal
anyway.

The good news (although with your logic, probably irrelevant) is that I
realized I could print these to pdf at 600dpi, effectively downsizing the
file. Of course, I have no idea what else the conversion might be doing to
the images (compression, etc). At least in initial tests, it seems to print
with sufficient clarity for our needs, and the file dropped from 30MB to
about 2MB- a heck of an improvement either way.

Thanks again for the logical explanation - next time I won't worry so much!
Keith