mac to pc - colors all washed out!!!
jpmcgrath
recently attempted to have "hard copy" slides made as a backup.
The slides came back with the images all "washed out" - like they
were overexposed. The problem appears to be a cross-platform
issue (they were using a PC to image the slides). When my
presentation is viewed on a PC all of the slides appear to be
drained of color. I have a number of slides with images imported
as .tif files out of Illustrator, and these are especially hard hit -
details and colors are bleached out. Meanwhile, everything looks
just fine on my Mac.
I'm not sure this matters, but the Illustrator files were converted to
RGB before being exported in tif format and underwent LZW
compression. If I use jpeg or some other format, too much detail
is lost - the images look lousy.
What gives?
Can presentations created on a Mac be shown using a PC?
Is there some way around this?
thx,
jpm
Steve Rindsberg
> recently attempted to have "hard copy" slides made as a backup.
> The slides came back with the images all "washed out" - like they
> were overexposed. The problem appears to be a cross-platform
> issue (they were using a PC to image the slides). When my
> presentation is viewed on a PC all of the slides appear to be
> drained of color. I have a number of slides with images imported
> as .tif files out of Illustrator, and these are especially hard hit -
> details and colors are bleached out. Meanwhile, everything looks
> just fine on my Mac.
This sounds like a gamma correction problem.
Different gamma correction values make an image look darker or lighter and
could lead to it's appearing washed out.
Do you have gamma correction software active on the Mac (Photoshop installs
it, probably) or is it active on the PC?
Or heaven forbid, do you have color correction and/or gamma correction
taking place on more than one different level or by multiple programs?
The result is something like choosing colors wearing heavily tinted blue
glasses in a very dark room. No surprise when your choices look a little
odd in daylight w/o the specs. ;-)
> I'm not sure this matters, but the Illustrator files were converted to
> RGB before being exported in tif format
Did you judge the color based on what you saw after the conversion?
>>and underwent LZW
> compression. If I use jpeg or some other format, too much detail
> is lost - the images look lousy.
LZW is lossless compression. It would have *no* effect on image quality at
all, where JPG will, as you've seen.
You done good.
jpmcgrath
problem if it is due to gamma correction issues. Should I assume
the digital imaging slide service guys have gamma correction
activated on their PC's?
I thought the problem may have to do with the TIF format , what
with the alpha layer and all this other hoo-ha that I don't quite
follow. I tried switching to PNG to import the images into PPT and
guess what - they came out all washed out looking. Even if
background color of the origin image was set to known RGB
values, it didn't match the slide background which was set to the
same values - the imported PNG image was much lighter/
bleached out.
So, I can reproduce the bleaching out phenomenon that I see
when going from Mac to PC just by using PNG as my format for
image transfers. What does this mean? What is PNG exactly that
it serves to emulate the platform cross-over effect? Does this lend
more insight as to what's going on, or does it just confuse matters
more???
jpm
>.
>
Steve Rindsberg
news:002c01c2ce62$c55d7b30$2f01...@phx.gbl...
> thanks for the feedback - I'm unsure as to how to sort out the
> problem if it is due to gamma correction issues. Should I assume
> the digital imaging slide service guys have gamma correction
> activated on their PC's?
More likely at your end. Imagine it like this - you have the brightness and
contrast cranked all the way down on your monitor. I dunno why. It's April
1 and your officemate's in a silly mood maybe. ;-)
You pull up an image in Photoshop and think "Hmm. Looks pretty dark. And
the contrast isn't so hot either."
So you fiddle the image in PShop until it looks right on your monitor ...
but of course, on my monitor, it's gonna look really funny. And print that
way, even though what it looks like on my monitor has no effect on what it
looks like when I print it.
> background color of the origin image was set to known RGB
> values, it didn't match the slide background which was set to the
> same values - the imported PNG image was much lighter/
> bleached out.
Makes it all the more likely to be a color management issue. PowerPoint
doesn't do any to speak of. x x x RGB in, x x x RGB out. Photoshop tries
to manage color like mad. That's fine if you have the right profiles set up
and all but necessary if you're printing to a CMYK output device, but PPT is
RGB. You're going RGB to RGB so there's no NEED for any color management,
to speak of. You'll need to figure out how to turn it OFF in Photoshop.
Blues
similar and that is what resolved it.
"Steve Rindsberg" <ab...@localhost.com> wrote in message news:<eoEVB0rzCHA.1924@TK2MSFTNGP12>...