![](/i/fill.gif) |
![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
Does the assumed_gamma global setting affect the gamma of the actual
image file produced or only the image displayed on my monitor?
- --
- -The Developer
"Hope is the last to die.......unlike the ICQ flower
-----BEGIN PGP SIGNATURE-----
Version: PGPfreeware 6.5.2 for non-commercial use <http://www.pgp.com>
iQA/AwUBOSy6W+uicZjHwGIQEQIMCQCfQrb6WYieCJaohN/9AEQJm8mqbMoAn15D
3RqcRkzJnq5du4VvVmNrKB38
=kiNy
-----END PGP SIGNATURE-----
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
A change in image file. Just don't know exactly how it works, except
that a darker or brighter render is still going to be darker or brighter
on other monitors too.
Bob
"The "D"" <the### [at] netzero net> wrote in message
news:392cbc04@news.povray.org...
Does the assumed_gamma global setting affect the gamma of the actual
image file produced or only the image displayed on my monitor?
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
The \"D\" wrote:
> Does the assumed_gamma global setting affect the gamma of the actual
> image file produced or only the image displayed on my monitor?
assumed_gamma and Display_Gamma in master povray.ini work together
to produce consistent results when the file is rendered in
different systems. It does not help correct color communication
in image files between systems.
The image data is gamma corrected by Display_Gamma/assumed_gamma.
If there is no assumed_gamma image data is not touched. In new
files assumed_gamma should always be 1.0 if it is used at all
because it's there to match old scene files with Display_Gamma.
You would set assumed_gamma the old display's gamma. This way
the "gamma correction" that was built in the old scene file
cancels out when POV applies the new correction.
Use http://www.povray.org/binaries/gamma.gif to find the correct
Display_Gamma.
Use http://hammer.prohosting.com/~kkivisal/adjust.gif to correctly
adjust monitor brightness and contrast.
There is a proposed standard for RGB images that is backwards compatible
,excellent for Internet and enables other people see your work of art
the way you intented.
sRGB: gamma 2.2, primaries HDTV, white point 6500K.
http://www.sRGB.com.
-----------------------------------------------------------------------
Kari Kivisalo www.kivisalo.net
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
Kari Kivisalo <kar### [at] kivisalo net> wrote in message
news:392FE712.F9B5A13B@kivisalo.net...
> assumed_gamma and Display_Gamma in master povray.ini work together
> to produce consistent results when the file is rendered in
> different systems. It does not help correct color communication
> in image files between systems.
>
> The image data is gamma corrected by Display_Gamma/assumed_gamma.
> If there is no assumed_gamma image data is not touched. In new
> files assumed_gamma should always be 1.0 if it is used at all
> because it's there to match old scene files with Display_Gamma.
> You would set assumed_gamma the old display's gamma. This way
> the "gamma correction" that was built in the old scene file
> cancels out when POV applies the new correction.
Ok this is basicly what the manual said about it (which I don't
completely understand). I asked mainly to see if assumed_gamma affected
the gamma if the resulting image as well as the image that is displayed
(in my case via the win32 pov engine with out any work needed on my
part) by the +D option. My moniter is old a decripit and it requires a
gamma correction of 1.85- (according to terragen's gamma adjuster which
seems so far to be accurate). Is there a way to adjust the gamma for my
monitor with out making the image too bright on newer/better monitors.
I'm making a web logo so this particular scene (and other various web
graphics I happen to make) so the scene isn't likely to be re-rendered
by anyone else.
> Use http://www.povray.org/binaries/gamma.gif to find the correct
> Display_Gamma.
>
> Use http://hammer.prohosting.com/~kkivisal/adjust.gif to correctly
> adjust monitor brightness and contrast.
>
>
> There is a proposed standard for RGB images that is backwards
compatible
> ,excellent for Internet and enables other people see your work of art
> the way you intented.
>
And just when will the proposal be finaized and by whom? That will be a
great thing when it's done (hope some one like iso, w3c, or ansi does it
they've got the most experience)
--
-The Developer
"Hope is the last to die.......unlike the ICQ flower
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
Bob Hughes <per### [at] aol com?subject=PoV-News:> wrote in message
news:392cc802@news.povray.org...
> A change in image file. Just don't know exactly how it works, except
> that a darker or brighter render is still going to be darker or
brighter
> on other monitors too.
Blah, that's what I was afriad of. My monitor is old and dying (very
slowly and painfully might I add) and as such is very dark (gamma 1.85
or so it what I've currently got close to accurate). Is there a way to
render an image and only have the display it gives me (the render window
in the win32 build of pov) and not the actual image file (it's a web
logo)
--
-The Developer
"Hope is the last to die.......unlike the ICQ flower
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
Soooo, you are saying you have adjusted the monitor already... not the assumed_gamma
alone? Sounds like you have something very much like my old DELL 486SX33 (or was it
33SX486... no matter).
That thing was dark when I turned the brightness up full, minus a fraction to prevent
distortion. Contrast too, I could never get a good screen.
Once I knew about it, just as you have found, all I did was to try and render
everything
darker. Once I had a new computer with monitor I saw washed out images galore of all
my
previous ray traces. Awful.
The thing you'll be having trouble with is to see things good AND for others to see
them
well also. Can't be done unless you keep switching things around.
Think you're going to have to guesstimate about it. Simply reason the renders to need
darkening and more contrast. In POV terminology, less ambience and more gamma
(meaning
in POV, more). The Povray.ini (master INI) file can be set to have a starting point
for
gamma as well. Display_Gamma=2.2 for PCs or 1.0 for Macs for example (no command-line
equivalent). As to what exactly will be the right setup would require you view the
renderings with another monitor for comparison probably.
Don't know what else I can say. Perhaps people here have more to say (and know).
Bob
"The "D"" <the### [at] netzero net> wrote in message
news:3931fc72@news.povray.org...
Kari Kivisalo <kar### [at] kivisalo net> wrote in message
news:392FE712.F9B5A13B@kivisalo.net...
> assumed_gamma and Display_Gamma in master povray.ini work together
> to produce consistent results when the file is rendered in
> different systems. It does not help correct color communication
> in image files between systems.
>
> The image data is gamma corrected by Display_Gamma/assumed_gamma.
> If there is no assumed_gamma image data is not touched. In new
> files assumed_gamma should always be 1.0 if it is used at all
> because it's there to match old scene files with Display_Gamma.
> You would set assumed_gamma the old display's gamma. This way
> the "gamma correction" that was built in the old scene file
> cancels out when POV applies the new correction.
Ok this is basicly what the manual said about it (which I don't completely
understand).
I asked mainly to see if assumed_gamma affected the gamma if the resulting image as
well
as the image that is displayed (in my case via the win32 pov engine with out any work
needed on my part) by the +D option. My moniter is old a decripit and it requires a
gamma correction of 1.85- (according to terragen's gamma adjuster which seems so far
to
be accurate). Is there a way to adjust the gamma for my monitor with out making the
image too bright on newer/better monitors. I'm making a web logo so this particular
scene (and other various web graphics I happen to make) so the scene isn't likely to
be
re-rendered by anyone else.
> Use http://www.povray.org/binaries/gamma.gif to find the correct
> Display_Gamma.
>
> Use http://hammer.prohosting.com/~kkivisal/adjust.gif to correctly
> adjust monitor brightness and contrast.
>
>
> There is a proposed standard for RGB images that is backwards compatible
> ,excellent for Internet and enables other people see your work of art
> the way you intented.
>
And just when will the proposal be finaized and by whom? That will be a great thing
when
it's done (hope some one like iso, w3c, or ansi does it they've got the most
experience)
--
-The Developer
"Hope is the last to die.......unlike the ICQ flower
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
Bob Hughes wrote:
>
> The Povray.ini (master INI) file can be set to have a starting point for
> gamma as well. Display_Gamma=2.2 for PCs or 1.0 for Macs for example (no
command-line
> equivalent).
Standard Mac gamma is 1.8, not 1.
--
Xplo Eristotle
http://start.at/xplosion/
"And then one day you find ten years have got behind you
No one told you when to run, you missed the starting gun"
-Pink Floyd
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
Thanks for correcting me, I need to be more often than not.
I was thinking of the assumed_gamma 1.0 of course which has been found in many scene
files although I still don't see how that's usable at all, even for the Mac. I
shouldn't have mentioned the Mac to begin with, something I don't know about. Sorry
all.
Bob
"Xplo Eristotle" <inq### [at] unforgettable com> wrote in message
news:39329F3B.5B20081F@unforgettable.com...
|
| Bob Hughes wrote:
| >
| > The Povray.ini (master INI) file can be set to have a starting point for
| > gamma as well. Display_Gamma=2.2 for PCs or 1.0 for Macs for example (no
command-line
| > equivalent).
|
| Standard Mac gamma is 1.8, not 1.
|
| --
| Xplo Eristotle
| http://start.at/xplosion/
|
| "And then one day you find ten years have got behind you
| No one told you when to run, you missed the starting gun"
| -Pink Floyd
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
Bob Hughes <per### [at] aol com?subject=PoV-News:> wrote in message
news:393217dc@news.povray.org...
> Soooo, you are saying you have adjusted the monitor already... not the
assumed_gamma
> alone? Sounds like you have something very much like my old DELL
486SX33 (or was it
> 33SX486... no matter).
> That thing was dark when I turned the brightness up full, minus a
fraction to prevent
> distortion. Contrast too, I could never get a good screen.
Actually both contrast and brighness are all the way up (could be why my
monitor is dying ;) and there's no bluring
> Once I knew about it, just as you have found, all I did was to try and
render everything
> darker. Once I had a new computer with monitor I saw washed out
images galore of all my
> previous ray traces. Awful.
> The thing you'll be having trouble with is to see things good AND for
others to see them
> well also. Can't be done unless you keep switching things around.
> Think you're going to have to guesstimate about it. Simply reason the
renders to need
> darkening and more contrast. In POV terminology, less ambience and
more gamma (meaning
> in POV, more). The Povray.ini (master INI) file can be set to have a
starting point for
> gamma as well. Display_Gamma=2.2 for PCs or 1.0 for Macs for
example (no command-line
> equivalent). As to what exactly will be the right setup would require
you view the
> renderings with another monitor for comparison probably.
> Don't know what else I can say. Perhaps people here have more to say
(and know).
Well it actually seems to be coming out in the wash since I forgot to
mention that the assumed_gamma value is 1.85 with a light source set at
1.5
times the intensity of "white" light. even at 1.85 with a regular white
light source the scene is too dark.
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |