Am 3/20/2018 um 8:43 schrieb Thomas de Groot:
> Once in a while, I like to revisit an older scene and remodel it to 
> current standards and my changing insights and skills. I did this lately 
> with my entry to the TC-RTC back in 2008: "N". I still want to change 
> some elements but the comparison over ten years of using POV-Ray are 
> notable. Left, is the entry of 2008; right, the new version.
> 

Sorry, but overall I do prefer the original.
The new version seems quite over-saturated, especially the vegetation, 
the bricks and the wheel.
While the new camera view is nice it has the unfortunate side effect 
that two birds of the flock are very close to the top border and this 
hurts the composition.

And a general note to everybody who's posting images to theses 
newsgroups: please make sure your JPEG image contains a ICC profile. 
Since about 2 months Firefox and Thunderbird have full color management 
enabled by default. Chrome and Opera do the same since quite a while, 
only IE and Edge don't - but who uses them anyway?
Every contemporary mid-range monitor has a wider color gamut than sRGB, 
the one I use even wider than Adobe RGB - and I can assure you, the 
difference is NOT subtle.
When I want to make sure to view an image as intended I have to do a few 
additional steps and as I'm lazy I usually don't care. As color 
management only kicks in for images with ICC profiles I have to save the 
image to my local disk and check *if* it contains a profile and if not 
use my own image viewer that correctly assumes for images without 
profile to be in sRGB and transforms them correctly to my viewing device 
profile.

-Ive

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On 21/03/2018 10:52, Ive wrote:
> 
> And a general note to everybody who's posting images to theses 
> newsgroups: please make sure your JPEG image contains a ICC profile.

How do I do that? Does it apply to PovRay generated png's?


-- 

Regards
     Stephen

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On 21-3-2018 11:52, Ive wrote:
> Am 3/20/2018 um 8:43 schrieb Thomas de Groot:
>> Once in a while, I like to revisit an older scene and remodel it to 
>> current standards and my changing insights and skills. I did this 
>> lately with my entry to the TC-RTC back in 2008: "N". I still want to 
>> change some elements but the comparison over ten years of using 
>> POV-Ray are notable. Left, is the entry of 2008; right, the new version.
>>
> 
> Sorry, but overall I do prefer the original.
> The new version seems quite over-saturated, especially the vegetation, 
> the bricks and the wheel.

I agree for the vegetation, maybe the wheel, not really for the bricks. 
However, my question would be: where does over-saturation come from?

It is strange. The original is - imo - strongly under-saturated.

> While the new camera view is nice it has the unfortunate side effect 
> that two birds of the flock are very close to the top border and this 
> hurts the composition.

Yes. You are perfectly right. Another reason to revisit the birds.

> 
> And a general note to everybody who's posting images to theses 
> newsgroups: please make sure your JPEG image contains a ICC profile. 
> Since about 2 months Firefox and Thunderbird have full color management 
> enabled by default. Chrome and Opera do the same since quite a while, 
> only IE and Edge don't - but who uses them anyway?
> Every contemporary mid-range monitor has a wider color gamut than sRGB, 
> the one I use even wider than Adobe RGB - and I can assure you, the 
> difference is NOT subtle.
> When I want to make sure to view an image as intended I have to do a few 
> additional steps and as I'm lazy I usually don't care. As color 
> management only kicks in for images with ICC profiles I have to save the 
> image to my local disk and check *if* it contains a profile and if not 
> use my own image viewer that correctly assumes for images without 
> profile to be in sRGB and transforms them correctly to my viewing device 
> profile.
> 

Hmmm... I don't know how to achieve that...

-- 
Thomas

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On 03/20/2018 03:43 AM, Thomas de Groot wrote:
> Once in a while, I like to revisit an older scene and remodel it to
> current standards and my changing insights and skills. I did this lately
> with my entry to the TC-RTC back in 2008: "N". I still want to change
> some elements but the comparison over ten years of using POV-Ray are
> notable. Left, is the entry of 2008; right, the new version.

It looks better in most respects.  I see 3 areas that seem 
over-corrected, though:

The corrosion on the plaque is overdone.  It's not that it's 
unrealistic, but that the text is mostly illegible.

The vegetation, while in isolation it looks better than the original, is 
distracting from the composition (for that very reason).

The new skin tones look overly saturated, although they are better than 
in the original.

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Am 3/21/2018 um 13:11 schrieb Thomas de Groot:
> I agree for the vegetation, maybe the wheel, not really for the bricks. 
> However, my question would be: where does over-saturation come from?
> 
Gamma! In the ancient time of MegaPOV and its unawareness of gamma 
handling you as the user had to tweak scene colors and lighting to 
compensate for the resulting inconsistency. Now with proper gamma 
handling but some of these *tweaks* making it over results in 
over-saturation and slightly hue shifts - as to be expected.

> It is strange. The original is - imo - strongly under-saturated.
>
Yes, I agree - saturation is certainly also a matter of taste - 
personally I can live with under-saturation better than with 
over-saturation.

> 
> Hmmm... I don't know how to achieve that...
> 

Contemporary versions of Photoshop and Lightroom do this auto-magical, 
older version if you told them to do so and I'm under the assumption 
this is also true for other software like Gimp or Paintshop. I do not 
use the latter so maybe I'm wrong?

-Ive

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Am 3/21/2018 um 12:30 schrieb Stephen:
> On 21/03/2018 10:52, Ive wrote:
>>
>> And a general note to everybody who's posting images to theses 
>> newsgroups: please make sure your JPEG image contains a ICC profile.
> 
> How do I do that? 

See my reply to Thomas.

> Does it apply to PovRay generated png's?
> 
PNG's are a very sad story and the ones generated by POV-Ray are no 
exception. For short: there is absolutely no way you can predict what 
anybody else will see when you post a PNG on the web. And there is no 
way to work around this.

-Ive

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Am 21.03.2018 um 11:52 schrieb Ive:

> And a general note to everybody who's posting images to theses
> newsgroups: please make sure your JPEG image contains a ICC profile.
> Since about 2 months Firefox and Thunderbird have full color management
> enabled by default. Chrome and Opera do the same since quite a while,
[...]
> As color
> management only kicks in for images with ICC profiles I have to save the
> image to my local disk and check *if* it contains a profile and if not
> use my own image viewer that correctly assumes for images without
> profile to be in sRGB and transforms them correctly to my viewing device
> profile.

I'd call that a bullshitty implementation then. After all, the W3C
officially recommends sRGB for all web content, so that's what browsers
should default to if an ICC profile is not embedded.

Also, a lot of images posted here are rendered with POV-Ray, which
currently does not embed an ICC profile. So to comply with your request,
each and every image would have to be post-processed before posting,
which I consider unreasonable.

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Am 21.03.2018 um 14:14 schrieb Ive:

> PNG's are a very sad story and the ones generated by POV-Ray are no
> exception. For short: there is absolutely no way you can predict what
> anybody else will see when you post a PNG on the web. And there is no
> way to work around this.

... which, I'd like to emphasize, is not POV-Ray's fault: If output is
set to `File_Gamma=sRGB` (the default), POV-Ray embeds an sRGB chunk,
which according to the PNG standard should communicate plain as hell
that the colour space is supposed to be sRGB.

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Am 21.03.2018 um 13:11 schrieb Thomas de Groot:

> I agree for the vegetation, maybe the wheel, not really for the bricks.
> However, my question would be: where does over-saturation come from?
> 
> It is strange. The original is - imo - strongly under-saturated.

Those are Poser figures, so I presume their materials also use Poser
texture images.

MegaPOV 1.2.1 - being based on POV-Ray v3.6 - completely ignored gamma
for input images; if you already used `assumed_gamma 1.0` back then - as
every good sailor should - MegaPOV 1.2.1 / POV-Ray v3.6 would
erroneously presume the input images to match that gamma.

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On 21-3-2018 14:07, Ive wrote:
> Am 3/21/2018 um 13:11 schrieb Thomas de Groot:
>> I agree for the vegetation, maybe the wheel, not really for the 
>> bricks. However, my question would be: where does over-saturation come 
>> from?
>>
> Gamma! In the ancient time of MegaPOV and its unawareness of gamma 
> handling you as the user had to tweak scene colors and lighting to 
> compensate for the resulting inconsistency. Now with proper gamma 
> handling but some of these *tweaks* making it over results in 
> over-saturation and slightly hue shifts - as to be expected.
> 
>> It is strange. The original is - imo - strongly under-saturated.
>>
> Yes, I agree - saturation is certainly also a matter of taste - 
> personally I can live with under-saturation better than with 
> over-saturation.

Then the short answer is clear: My latest scene version using 
exclusively sRGB gamma all through (and gamma 1.0 where necessary) the 
apparent over-saturation is solely due to the original hue of the used 
image_maps. I can live with that although I prefer a slightly 
less-saturated version; it might me make to consider to tweak the 
original images to a "lighter", "flatter" hue, or to apply a colour 
transformation within POV-Ray.

> 
>>
>> Hmmm... I don't know how to achieve that...
>>
> 
> Contemporary versions of Photoshop and Lightroom do this auto-magical, 
> older version if you told them to do so and I'm under the assumption 
> this is also true for other software like Gimp or Paintshop. I do not 
> use the latter so maybe I'm wrong?
> 

I am using Gimp and have not (yet) found thematter. Does your IC do it 
by the way?

-- 
Thomas

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