iPhoto 2 and ColorSync: Use ImageCapture to embed sRGB profile for better sharing and printing
John Faughnan
"iPhoto 2.0 does use ColorSync. It honors embedded ICC profiles. But,
since it's a consumer application, there are no tools for embedding
profiles. You would need to use AppleScript or an application like
Photoshop or even GraphicConverter.
To produce JPEGs that will look the same on a Mac and a PC, you should
embed the sRGB profile. We ship this profile as part of Mac OS X. It's
in System/Library/ColorSync/Profiles/."
A few comments:
1. It's great that Apple's ColorSync support people responded to my
inquiry!
2. It's good that iPhoto 2 will support ColorSync (by implication
iPhoto 1 did not, which is amazing.)
3. I think some of the problems (dark images, low brighness) iPhoto
users have with printing shots on consumer printing services and
sharing with PC users are due to iPhoto's lack of support for
embedding profiles.
4. I think Apple needs to get beyond using the "consumer application"
excuse for some basic design flaws (such as lack of scaling beyond
1000 images with titles and comments, and lack of profile embedding).
Just because consumers don't think about these things doesn't mean
then don't need them.
5. OS X Image Capture can embed color sync profiles. It can also be
set to launch on startup instead of passing off immediately to iPhoto.
I'm going to set Image Capture to take my images first, then embed the
sRGB profile, then pass them off to iPhoto.
[meta: jfaughnan, jgfaughnan, iPhoto, digital photography, digicam,
Apple, OS X, Macintosh, iPhoto, ColorSync, ICC, sRGB, workflow,
standards, Windows, display, 030202]
Jeremy
> "iPhoto 2.0 does use ColorSync. It honors embedded ICC profiles. But,
> since it's a consumer application, there are no tools for embedding
> profiles. You would need to use AppleScript or an application like
> Photoshop or even GraphicConverter.
>
> To produce JPEGs that will look the same on a Mac and a PC, you should
> embed the sRGB profile. We ship this profile as part of Mac OS X. It's
> in System/Library/ColorSync/Profiles/."
I would question the wisdom of blindly tossing sRGB into everything. It's
a not-very-wide-gamut profile for PC monitor display and/or cheap printers.
It probably does result in colors that "look the same on a Mac and a PC",
but that might be at the expense of quality, especially if you're going to
print for real or do any serious manipulation (probably fine for putting
pictures on web pages or in email).
--
Jeremy | jer...@exit109.com
John Faughnan
> I would question the wisdom of blindly tossing sRGB into everything. It's
> a not-very-wide-gamut profile for PC monitor display and/or cheap printers.
> It probably does result in colors that "look the same on a Mac and a PC",
> but that might be at the expense of quality, especially if you're going to
> print for real or do any serious manipulation (probably fine for putting
> pictures on web pages or in email).
Jeremy,
What color profiles do you recommend for:
1. sending a file out for printing with Kodak (ofoto) or Shutterfly?
2. distributing an 800x600 picture on the web for viewing by PC or
Mac?
3. viewing on an iBook with ColorSync settings for the LCD?
I realize that the best solution would be for iPhoto to insert an
appropriate color profile at the time that one exports for web or
uploads for printing, but does it do that?
Thanks,
john
[meta: jfaughnan, jgfaughnan, iPhoto, colorSync, color profile, ICC,
sRGB, adobe, digicam, digital photography, digital camera]
Jeremy
>> It's a not-very-wide-gamut profile for PC monitor display and/or cheap
>> printers. It probably does result in colors that "look the same on a
>> Mac and a PC", but that might be at the expense of quality, especially
>> if you're going to print for real or do any serious manipulation
>> (probably fine for putting pictures on web pages or in email).
>
>
> 1. sending a file out for printing with Kodak (ofoto) or Shutterfly?
> 2. distributing an 800x600 picture on the web for viewing by PC or
> Mac?
> 3. viewing on an iBook with ColorSync settings for the LCD?
Lately I've been using Adobe RGB 1998 as my working space in Photoshop
and such, and I have my monitors calibrated with a gamma of 2.2. The
Adobe profile has a fairly wide color gamut.
Macs use a gamma of 1.8 by default, which is significantly ligher than
a PC display, which is what leads to the problem of images looking too
dark.
What you want to do is calibrate your monitor, and then use the profile
the calibration generates as your monitor profile in the Color tab of
the Display preferences. The monitor profile is used for display, and
isn't what gets embedded into the pictures themselves; it is unique to
your monitor. You do *not* want to use your monitor profile as your
working space; this is essentially the same as not using color management
at all.
If you don't have a monitor calibration device, you can use SuperCal
to calibrate it by eye. http://www.bergdesign.com/supercal/
The result probably won't be quite as good as using a calibration
device, but it will still be good if you follow the instructions and
do it right.
The working space is the one which gets embedded into the pictures.
Since the colors always go through this space, you need something which
can reproduce all the colors you'll eventually need on output. The Adobe
RGB 1998 one seems to be a good general choice for this. I'm not
entirely sure if it ships with OS X by default, but if you install
Photoshop or probably any of the Adobe graphics programs, you'll have it.
I've set that as my default RGB working space in the Colorsync prefs,
as well as in Photoshop, Illustrator, etc.
For best results, you also need a profile specific to your *input* device
from which the colors can be translated into the working space. This
would mean using a profile for your specific camera or scanner. However,
if you don't have one, as long as you've calibrated your monitor and are
using an appropriate working space *and* a profile for your output device
(if you're printing or whatever), what you see on the monitor should at
least be very close to what you get, so once you import a picture, you
can correct the colors on-screen with confidence. I don't have a profile
for my scanner (I really should get what I need to generate one), and the
colors always seem to come out magenta-heavy, but once I correct them,
all is well, or at least it has been so far.
--
Jeremy | jer...@exit109.com
John Faughnan
[extensive discussion of color profile embedding:
http://groups.google.com/groups?hl=en&lr=lang_en&ie=UTF-8&threadm=1044391438.182%40ok-corral.gunslinger.net&rnum=1]
Jeremy, that's the most extensive short course on ColorSync and color
profiles I've seen. I'm sure I didn't follow it all, but I'll reread
it a few times. These are the key items I extracted:
1. Use http://www.bergdesign.com/supercal/ to support manual
calibration of my monitor. (At this time I just have ColorSync set to
use the LCD profile for my iBook.)
2. Use Adobe RGB Color profiles. (I think I have this.)
3. Use Apple's ColorSync utility to set the input profile for my Canon
G2 and Epson scanner to the appropriate settings (the EPSON TWAIN
facility does this too.)
However, if I do all this and the image looks fine on my Mac, how will
it look to someone viewing it on a PC using IE 6?
john
[meta: jfaughnan, jgfaughnan, iPhoto, colorSync, color profile, ICC,
sRGB, adobe, digicam, digital photography, digital camera, 030203]
John Faughnan
I replied to your posting in a separate message (THANK YOU), but the
more I read on this the more confused I am.
How is this all supposed to work? Assuming everything I used is
ColorSync aware and all the Color Profiles are correct, is the theory
that:
1. the editing application I use "knows" the color profile of the
image creator and the color profile of my monitor. So it adjusts the
display to suit my monitor.
2. I get the image looking good and send it on its way. At that point,
what color profile should the image contain? (Original source color
profile, editing tool color profile, display color profile, or (if the
display will be on an PC running IE 6) an sRGB profile? My limited
research suggests that the only browser that honors color profile
settings is IE/Mac (though Safari might). Since the PC browser will
ignore all my good color profile work, maybe I should use sRGB and
adjust the images for that? (Sigh, this is frustrating!)
john
Jeremy
> 1. Use http://www.bergdesign.com/supercal/ to support manual
> calibration of my monitor. (At this time I just have ColorSync set to
> use the LCD profile for my iBook.)
That's better than nothing, but yeah, it's god to calibrate yours because
monitors can vary from one to another.
> 2. Use Adobe RGB Color profiles. (I think I have this.)
I can't *prove* that's the best choice, but it seemed to be, among the
choices, to me.
> 3. Use Apple's ColorSync utility to set the input profile for my Canon
> G2 and Epson scanner to the appropriate settings (the EPSON TWAIN
> facility does this too.)
Yep. It is best, again, to calibrate your individual scanner; if you don't
you should definitely look at the images (on your calibrated monitor) to make
sure they look okay. Of course, you can't easily calibrate a scanner by
eye, so this requires some doing.
> However, if I do all this and the image looks fine on my Mac, how will
> it look to someone viewing it on a PC using IE 6?
That's why I use a gamma of 2.2 on my displays. You'll see something much
closer to what a PC user will see, so you won't have to wonder. (I made
a profile for a 1.8 gamma, too, but I rarely use it as I rarely do any
kind of print work anymore; I'm just a hobbiest these days.)
--
Jeremy | jer...@exit109.com
Jeremy
> I replied to your posting in a separate message (THANK YOU), but the
> more I read on this the more confused I am.
Unfortunately, there is very little hard information out there about how
to use Colorsync. You don't even want to know how much time I've spent
digging for it. :)
> 2. I get the image looking good and send it on its way. At that point,
> what color profile should the image contain?
The profile that ends up in the image is the working space profile (the
Adobe RGB 1998 one, in my example). You have adjusted the colors on your
display, and since you have profiles for your display and for the image,
the image "knows" what you mean by a given color. The theory being that
on output to a different device, the colors can be translated to that
device's profile and end up looking the way they looked on your monitor,
because Photoshop (or whatever) "knew" what you meant by a certain color.
> My limited research suggests that the only browser that honors color
> profile settings is IE/Mac (though Safari might). Since the PC browser
> will ignore all my good color profile work, maybe I should use sRGB and
> adjust the images for that? (Sigh, this is frustrating!)
Once you're using a calibrated monitor and all that, you adjust the image
so that it looks "right" to you, and in theory, you've done it properly.
If a PC user views it, without any kind of color management, any difference
he sees should then be down to *his* monitor being out of adjustment (which
you can't do anything about). The other main issue is that if you're using
the default gamma of 1.8 on your Mac, the PC user's display is going to
appear darker than yours -- so, what looked "right" to you might look too
dark to him. And, a printing service expecting images from a PC might
print them too dark, assuming they don't support ICC profiles. This is
why I adjust my gamma to 2.2. Having done that, I figure I don't need
to wonder.
I haven't entirely worked out how to deal with the whole gamma issue. I
do know, though, that Photoshop (in current versions) use 2.2 by default,
so by setting my monitor to that, I figure I'm good, as long as the image
looks good on my screen. Colorsync may provide a way to deal with this
more precisely, but I haven't found it yet.
--
Jeremy | jer...@exit109.com
John Faughnan
> The other main issue is that if you're using
> the default gamma of 1.8 on your Mac, the PC user's display is going to
> appear darker than yours -- so, what looked "right" to you might look too
> dark to him. And, a printing service expecting images from a PC might
> print them too dark, assuming they don't support ICC profiles. This is
> I haven't entirely worked out how to deal with the whole gamma issue. I
> do know, though, that Photoshop (in current versions) use 2.2 by default,
> so by setting my monitor to that, I figure I'm good, as long as the image
Thank you again for sharing your experience! I'm a bit late replying,
it's been a busy week.
A couple of definitions from the Getty site and the ICC site, then
some comments.
1. Gamma: In monitors, the relationship between the voltage input and
the brightness of a monitor. This relationship is logarithmic. The
brightness of the monitor in relation to the voltage input is
expressed as x^2.2 where x is the voltage input and 2.2 is a power
function called gamma. Gamma can be thought of as a hard-wired
contrast curve.
2. sRGB: Standard RGB. An RGB specification promoted by Microsoft and
Hewlett-Packard. It specifies a gamma of 2.2 and a white point of
5000°K. [According to the sRGB spec,
http://www.w3.org/Graphics/Color/sRGB.html, gamma is the most
significant part of the sRGB spec.
Gamma is the big problem for sharing photos between Mac and PC. I went
to the ICC web site to learn more and I came away convinced that this
is a big hairy problem. They seem pretty persuaded that unless one is
a colorimetry guru, one should use an "sRGB" workflow. Unfortunately,
I don't know what "sRGB workflow" means on the Mac. In some ways, by
setting your monitor to a gamma of 2.2, you may effectively be doing
this.
I've heard sRGB is a smaller color space than Adobe RGB, but try
reviewing this arcane discussion on the color theory list --
http://www.ledet.com/margulis/ACT_postings/ACT-sRGBvsAdobeRGB.html.
One comment struck me in particular "The pessimist therefore optimizes
his files for sRGB and saves them without tagging to avoid confusing
as many users as possible. sRGB, it turns out, is not all that bad to
convert from into most flavors of CMYK and any reasonably
sophisticated user could deal with the color issues that
the more limited sRGB gamut presents."
I think if you review this list you'll have to concur:
1. if these guys can't agree, we don't have a hope in heck.
2. sRGB isn't perfect, but there are super-gurus who contend that it
may be a practical choice, and the ICC recommends sRGB for non-expert
users. (http://www.color.org/faq.html)
So, I think you've got a lot of support for your strategy of Adobe RGB
and gamma 2.2, but sRGB (which implies gamma 2.2) may work too. (Apple
RGB implies gamma 1.8).
So now I use option-brightness to open my display preferences
(option-brightness is an invaluable shortcut for accessing display
preferences). Using "calibrate" I create a new color profile with a
gamma of 2.0 and call it Gamma2 (these are stored in
~\Library\ColorSync\Profiles, I think they have to be deleted from the
Finder, but be sure they're not in use!)
I then switch between sRGB (gamma 2.2), my new Gamma2, and generic
RGB, Color LCD, EPSON Adobe RGB etc while observing a test image in
iPhoto. Only the first three make any difference, Color LCD and
Generic RGB and even EPSON Adobe RGB all look the same. With sRGB the
pictures look dull and dark, just like on a PC.
So I could set my display to sRGB profile. Images there look like on
my PC (gamma about 2.2) and presumably if they look right on the iBook
using sRGB they'll look ok on most PC cheapo image viewers that ignore
ICC profiles (like, for example, IE).
Problem is, with a gamma of 2.2 the rest of my Mac doesn't look so
good! Icons are dull, my image library is dull, etc!
I'm going to be very interested in repeating this experiment with
iPhoto 2 with its supposed ColorSync support.
For now I'm going to try embedding sRGB profiles into the images I
output, and I'll bias my Mac images towards being somewhat bright and
contrasty. I'll switch to my sRGB monitor setting to look over
pictures and decide which to boost, then switch back to LCD ColorSync
for most of my work. It's a dumb compromise, but it may be the best I
can do for now!
--
[meta: jfaughnan, jgfaughnan, iPhoto, digital photography, digicam,
Apple, OS X, Macintosh, iPhoto, ColorSync, ICC, sRGB, workflow,
standards, Windows, display, 030207]
Jeremy
> A couple of definitions from the Getty site and the ICC site, then
> some comments.
Thanks for the links, it's always nice to find more information about this
stuff.
> I think if you review this list you'll have to concur:
>
> 1. if these guys can't agree, we don't have a hope in heck.
Well, what you end up coming away with is the realization that there is
no such thing as "exact color". So you end up going for something that
works the way you want, rather than looking for the magic bullet.
> 2. sRGB isn't perfect, but there are super-gurus who contend that it
> may be a practical choice, and the ICC recommends sRGB for non-expert
> users. (http://www.color.org/faq.html)
>
> So, I think you've got a lot of support for your strategy of Adobe RGB
> and gamma 2.2, but sRGB (which implies gamma 2.2) may work too. (Apple
> RGB implies gamma 1.8).
Yeah. That discussion was the first I'd heard on the topic of sRGB from
people who clearly know more about this stuff than I do. :) However, I
did notice that the discussion was, largely, aimed at producing color
separations for print. Print has a more narrow color gamut than your
screen.
It's worth noting that my particular choices in this area would be based
on a couple of things: first of all, I literally never produce anything
intended for a printing press. Also, most of my stuff stays on-screen;
I most often show pictures to other people by showing them on my laptop
screen. I haven't done paying work for anyone else in years, so I don't
really worry about interoperating with someone else's workflow.
Further, I still haven't gotten a really good printer, so I'm actually
not using anything which requires me to generate color separations at
all. It's possible that using a good printer which actually takes CMYK
input (without converting it to RGB and back again) would require some
small changes in workflow.
Finally, I like strong color; I often actually intensify the colors in
pictures from the original, so I do want a wide gamut. If, however,
you're more interested in fine-grained representation of color nuances,
a wider RGB gamut might actually be a detriment. This was something I
had a strong feeling about, but the discussion you pointed me to had
people (who know more than I do) saying the same thing, so now I'm more
sure about it. :)
> So I could set my display to sRGB profile. Images there look like on
> my PC (gamma about 2.2) and presumably if they look right on the iBook
> using sRGB they'll look ok on most PC cheapo image viewers that ignore
> ICC profiles (like, for example, IE).
No! Don't use sRGB as your display profile. Use it as your working
space (the profile that gets embedded in the picture). If you use the
same profile for display as you use for your working space, then no color
adjustments are being made for display, and it's like not using color
management at all.
In theory, aside from the gamma issue, the only display profile you should
use is one you generate by calibrating your monitor. That's your output
profile for screen display on your system.
> Problem is, with a gamma of 2.2 the rest of my Mac doesn't look so
> good! Icons are dull, my image library is dull, etc!
You'll get used to it. :) Actually, 1.8 looks washed-out and too bright
to me, as I use 2.2 basically all the time. If you look at a graphic
made on a Mac for a Mac (icons, for example), you won't be seeing the
same thing the artist saw, but I think that's a worthwhile trade-off
since it means I'm not adjusting everything so that it ends up looking
too dark to most of the world. PCs use 2.2 (or even darker), television
uses 2.2, so I might as well join the club and use 2.2.
However, if you use sRGB, which actually specifies 2.2, as your working
space, then you could probably get away with leaving your monitor at 1.8.
I'd still want to switch to a 2.2 display just to check the images,
though.
When you switch to 2.2, if your image library looks dull, consider that
this is what it'll look like on a PC screen too.
--
Jeremy | jer...@exit109.com