Re: Media Testing for maclife.de (was: Re: Colorsync-users Digest, Vol 5, Issue 290)
Re: Media Testing for maclife.de (was: Re: Colorsync-users Digest, Vol 5, Issue 290)
- Subject: Re: Media Testing for maclife.de (was: Re: Colorsync-users Digest, Vol 5, Issue 290)
- From: Uli Zappe <email@hidden>
- Date: Tue, 9 Sep 2008 06:07:45 +0200
[Chris, it would make this much more manageable for the rest of us if
you could reply to the original topic, not some generic digest]
Am 09.09.2008 um 03:45 schrieb Chris Cox:
I'm sorry, I really don't see how you came to that conclusion.
How about reading what I wrote?
You tested profiles designed to match the Canon rendering - and they
did.
Yep, and I wrote that this is a nice result.
You tested it in a single light source situation
Not at all; I tested them with 7 different lighting scenarios, as I
clearly stated: "averaged over the 7 lighting scenarios of my
test" (which I described earlier in this thread).
(because ICC profiles cannot handle multiple light sources correctly)
They can (meaning they provide better results than e.g. Adobe's dual
approach default profiles in *every single* lighting condition from
bright sunlight to a halogen lamp in a dark room) - that was one of
the more interesting results of my test, and I reported it here. Did
you actually read anything of my review summary?
and concluded that they are very close.
Yes, and because that's what they are intended for this result is
fine, isn't it?
But the DNG Profiles are needed partly because ICC profiles are
limited to a single illuminant and cannot work with multiple
illuminants
If this is the case, then why do the best custom ICC profiles deliver
better results metrologically than any of Adobe's profiles? (In
*various* lighting scenarios!)
(at least not across multiple RAW development systems
??? Adobe profiles can also only be used with the Adobe RAW converter.
But you did no testing to see if DNG profiles could exceed the
quality/accuracy of the default rendering...
You mean by individually tweaking them?
If so, I already wrote why this approach is completely unfeasible in a
comparative review of this scope.
You know, Adobe isn't the hub of the universe although some people
here certainly behave as if it was. I cannot spend hours on one single
profile to see whether I could improve on Adobe's default if I have to
assess much more than 100 profiles each of which would have to be
treated in the same way (i.e. also tweaked to improve on it). I simply
have to assume that each vendor tried to deliver by default the best
they could deliver. This is common practice in reviews such as this.
and then conclude that they can't. That doesn't follow at all.
It does not follow that Adobe DNG profiles cannot be improved by
individual tweaking, but I never said that.
Either you are drawing some bad conclusions, or you are failing to
tell us about all of your testing. At best, I think that all you
could reasonably say based on your stated testing is that the DNG
profiles match the Canon rendering to within a certain deltaE.
My testing allows me to state the following:
1. Adobe's "Canon Faithful" emulation profile matches the original
profile within a small delta E in my 7 test lighting scenarios (not a
bad result at all ...)
2. Adobe's "Standard beta" profile fares worse metrologically than the
"Canon Faithful" emulation profile.
3. The (original) Canon "Faithful" profile is the metrologically best
profile of all profiles Canon delivers for my test camera.
4. Custom profiles built with ProfileMaker, Digital ColorChecker SG
and Capture One PRO deliver better metrological results than the Canon
"Faithful" profile (again, in *every single* of my 7 test lighting
scenarios).
5. Profiles built with the DNG Profile Editor and the ColorChecker 24
deliver results similar to that of Adobe's "Standard beta" profile.
Now I rely on 2 assumptions:
6. Adobe's emulation of original Canon profiles other than "Faithful"
are similarly close to their originals as the "Canon Faithful"
emulation is
7. Adobe tried to deliver the best default settings they could for
their "Standard beta" profile as well as for profiles resulting from
measurements of a ColorChecker 24 target with the DNG Profile Editor.
(Again, a comparative review has to make this assumption.)
So the conclusions from my testing are:
8. from 1 & 3 & 6 -> Adobe's "Canon Faithful" emulation profile is the
best of all of Adobe's Canon emulation profiles for my test camera
9. from 8 & 2 & 5 -> Adobe's "Canon Faithful" emulation profile is the
best of all of Adobe's profiles for my test camera
10. from 9 & 1 & 4 -> Custom profiles built with ProfileMaker, Digital
ColorChecker SG and Capture One PRO deliver better metrological
results than the best of all of Adobe's profiles for my test camera
9) is what I meant when I wrote that "Adobe, with its proprietary
technology, still can't improve on the best Canon factory profile".
Do you still not see how I came to that conclusion?
10) is what I meant when I wrote that ICC profiles deliver better
results than Adobe's profiles.
If "Adobe, with its proprietary technology, still can't improve on
the best Canon factory profile", this means that they were *not*
able to deliver *additional improvements* over the ICC format, and
hence, that their choice of a proprietary format was not justified,
at least in hindsight (Adobe might well have had good intentions).
Again, this is very bad logic.
You have drawn a conclusion that is completely unsupported by your
experiments.
Not so. This is 9 & 10 in other words.
So my reasoning is:
1. Everything else being equal, standard formats are better because
they allow choice.
2. Adobe chooses a proprietary format and explains this with
shortcomings of the ICC format (as quoted in this thread)
3. My measurements show the best results are achieved with ICC
profiles.
4. from 3) follows: there are no shortcomings in ICC profiles
relative
to Adobe's format.
5. from 1) and 4) follows: Adobe's choice of a proprietary format was
not the best solution
3, 4, and 5 are incorrect.
You did not test (3),
I did; see 10 above.
<Sigh> This is the whole point of it all! Of course, if my tests had
shown that Adobe's profiles are superior to ICC profiles (which was
what I actually expected when I began with my measurements!), I would
welcome this new technology. My whole point is nothing more than that
my measurements revealed Adobe's profiles are *not* superior to ICC
profiles, not even to Canon's default ICC profiles (step 9 from
above), but even more so when compared to custom ICC profiles (step 10
from above).
and thus 4 cannot be proven, and 5 does not follow
from 3 or 4 because you have not taken all the facts into
consideration.
I'm sorry, but you are still making incorrect statements,
I don't see where.
I still cannot figure out if you are doing this intentionally to
mislead or create arguments, or whether you simply do not have the
background to do this testing.
Are you saying that if someone does not agree with Adobe's POV, he
must be either a troll or stupid?
I'm doing this because I conducted measurements and they revealed
Adobe profiles, in their current implementation and within a practical
usage scenario, to be metrologically inferior to custom built ICC
profiles. I got numbers, and I reported them. It's called science.
Bye
Uli
________________________________________________________
Uli Zappe, Solmsstraße 5, D-65189 Wiesbaden, Germany
http://www.ritual.org
Fon: +49-700-ULIZAPPE
Fax: +49-700-ZAPPEFAX
________________________________________________________
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Colorsync-users mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden