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: Chris Cox <email@hidden>
- Date: Tue, 09 Sep 2008 17:36:41 -0700
- Thread-topic: Media Testing for maclife.de (was: Re: Colorsync-users Digest, Vol 5, Issue 290)
I do reply to the topic, but Entourage has it's own ideas and sometimes
changes things behind my back. Sadly, I have to use it in order to access
Adobe's calendaring system.
On 9/8/08 9:07 PM, "Uli Zappe" <email@hidden> wrote:
> [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?
I did, and what you wrote does not support the conclusion you gave.
>> (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?
A single ICC profile cannot account for multiple lighting conditions - that
is one of the big, well known, well understood limitations of ICC profiles.
How did you account for the different light sources using a single profile?
Or were you using an output (artistic intent) profile, not a camera
calibration profile?
>> 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!)
I don't know how they could, since the ICC profiles cannot handle multiple
lighting conditions by themselves.
Most likely you are not telling us something important about your test
procedure.
>
>> (at least not across multiple RAW development systems
>
> ??? Adobe profiles can also only be used with the Adobe RAW converter.
No, they can be used with any RAW converter that implements the (public) DNG
1.2 specification. And that has nothing to do with what I said.
>> 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.
In which case you cannot claim the conclusions you stated.
You did not test the DNG profiles to see if they could exceed the quality.
You only tested to see if they matched the software they were intended to
match - and they did.
You stated that Adobe's DNG Profile technology and methodology do not exceed
the quality of ICC profiles, which is something you failed to test.
> 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.
If stating incorrect and unsupported conclusions is standard practice for
your publication, then it needs to be labeled as a marketing document and
not a review.
>> 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.
You need to read what you wrote.
>
>> 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.
That is odd, since the Canon (and Nikon) default renderings are known to be
far from accurate (high contrast, high saturation, selective color
saturation boosts, etc.).
> 3. The (original) Canon "Faithful" profile is the metrologically best
> profile of all profiles Canon delivers for my test camera.
I'm starting to wonder about your standard of comparison here....
> 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.)
You cannot make assumption 6 or 7.
You have no idea what Adobe's targets were for those profiles.
>
> 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
"best" only if your target is Canon's default rendering.
It is not the most accurate by far.
> 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".
No, that statement does not follow from your tests.
>
> Do you still not see how I came to that conclusion?
No, because it is too broad and not supported by your testing.
>
> 10) is what I meant when I wrote that ICC profiles deliver better
> results than Adobe's profiles.
Again, that does not follow from your testing.
Again, it is too broad and not supported by your testing.
>
>>> 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.
Still incorrect, and still unsupported.
>
>>> 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).
Again, your testing revealed nothing of the sort.
>
>> 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?
No, but that you may not have the background to understand where you are
falling short in your analysis and conclusions.
You seem to be working at this pretty hard, but still making statements that
are unsupported by your experiments.
>
> 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.
No, you tested a few profiles, not the profile technology.
You can draw conclusions about the few profiles you tested, but not on the
entire technology (which you did not test).
Chris
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