Christoph Hormann wrote:
>Note that i did not suggest to make it brighter - the correct overall
>brightness is mostly a matter of the computer and monitor the image is
>shown on.  The really important thing that makes an image appear as sunny
>or not are the relations between the different parts of the scene.

I read somewhere that normal daylight is <1.0, 0.84, 0.57>*7.6  Of course
evening light would be considerably lower, maybe closer to *3.0

When I use really high values for sunlight, the light washes out surfaces
toward white, losing detail. I guess that's similar to what a camera does,
but I'm not necessarily trying to duplicate a camera view. On the Innocent
Shadow image I had to be careful not to wash out the sidewalk's texture
with too bright a sunlight (though maybe I should've sacrificed that detail
for realism?).

I would be interested in seeing the Radio Graves image adjusted using
HCR-Edit. Perhaps Jeremy would give his permission for this altered version
to be posted? I'm on a Mac so I don't have access to HCR-Edit to see the
difference.

Let's say the "exposure" was set to show the wood on the radios best, so the
grass is washed out a bit. This makes some sense to me, and Bill's
suggestion about the grass being dry and dusty also makes sense (though
there is no dust on the radios, as he mentioned). The scene looks hazy,
except the radios have not been out in the weather (appearing brand new).

I hope this isn't picking too many nits, but this kind of discussion is
really helpful to me!

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Slashdolt hammered this:
> Other thoughts...
> Overall, I tried to do this without using things like Poser, X-frog,
> pre-built models etc.  Probably because I don't own any of those things.
;-)
> But more to the point, since I don't own those things, I wanted to show
> what's possible using just POV-Ray, and a few other simple, mostly free
> tools.  I think some of the scoring may have taken that into account, but
> that's just my feeling.

Thats how I approach most of my images as well. Some things just cannot
be done with pure POV, like modelling realistic people. Programs like
Poser are fine for that. And for excellent plants, X-Frog is a path to
choose,
though nice gardens have been made without it.
For me, it takes the awe when I look at an image, and then see that it has
been done with X-Frog, Poser, Maya along with Mental Ray, and perhaps
Realwave or such. Unless the image has been composited very professionally,
like Gilles' "Not for sale anymore", I end up thinking that using THOSE
programs, something better could have been achieved very easily. That might
not be true, those programs aren't easy to handle, but when I see a pure
POV-image opposed to one made with the conventional $$$-programs, I
just keep thinking that most of the features are accessible with a click.

My Worldbowl image for the IRTC had been such an adventure, modelling and
texturing everything with pure POV, and its fun and a great learning
experience.

And as a little extra, I don't have to keep thinking that perhaps some day
someone might want to sue me, because I made an image with an illegal
copy of Maya. I've got an old Poser (hm. wanted to give thanks to the POVer
who sent it to me, but due to my recent System Crash, I can't find out...
Speak up, whoever it was! :-), and some programming skills (though I'm only
scripting in pure POV, its much more platform-independant that way :-)
and those two (and in most of the cases, only the last one) have made all
my images possible.

And "Gerberas"... No X-Frog used there. Not even one external program
used, actually.

POV-Ray rocks, baby! ;-)

--
Tim Nikias v2.0
Homepage: http://www.digitaltwilight.de/no_lights
Email: Tim### [at] gmxde

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I think I understand what you are saying.  For future reference, how would
you recommend correcting that?  Should I make the sun brighter by saying
something like "rgb <3,3,3>"?

Also, I set radiosity's "brightness" to 0.3, which may have made everything
appear darker.

--
Slash

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Slashdolt wrote:

>I've had mixed feelings about the farm myself.  But since I live in an area
>surrounded by farms, it was an easy place to get inspiration.  I would
>slowly drive by silos on my way home from work.  Many of them are rusty,
>which gives them much more character.  I hope to do a farm scene some day.
>Or perhaps several scenes.

I also live in a rural area and the weathered wood and rusted metal roofs
are very beautiful, in their own way. I've seen a lot of computer generated
scenes taking advantage of that, some of them quite realistic.

>The sunlight was quite yellow.  Additionally, there is a big yellow spot in
>the sky around it.  The grass began to look really blue when the radiosity
>would reflect it from the blue sky.  I made the sky a little more
>grey-white, and added the yellow gradient.

The sky sphere often overpowers scenes using radiosity in POV-Ray. Perhaps
the sun isn't bright enough?

>The fence was originally taller and closer.  It's only about 40" tall, IIRC.
>Any shorter, and it would have been less realistic.  It's also a few yards
>away from the radios, though it's difficult to tell.

Looking at the scene after reading this, I see what you say. I guess the
fence design has the appearance of a taller fence, or perhaps the corn
stalks are not as high (or as close) as I'd assumed, throwing off my
perception of the size of the radios as well.

>I spent countless hours working on the textures and finishes. Even so, I'm
>not 100% satisfied.  Maybe 90%.  I'm going from memory, but I believe the
>wood texture was a granite and bozo texture stretched out to look like a
>wood grain.  Then I overlayed a stretched agate pattern on top of that, for
>the color variation.  I tried using the woods.inc, but eventually abandoned
>it, and made my own.  Some of them also had turbulence added.  Then I used,
>"warp {repeat 2*x flip <1,0,0> " to flip-flop the textures to look like wood
>veneer.

I almost never get a good wood from wood, but use wrinkles and granite.

>Some things that went wrong...
>* Lighting:  It's too dark, imho, and I ran out of time before I could
>figure out what to do about it.
>* Focal blur:  A small amount of focal blur was necessary or the image_maps
>of the grille cloths looked very bad.  For the final render, I had set blur
>samples to 200, but it would have probably taken 3 months to render.  I
>ended up leaving it at 50 samples.  That caused some graininess, especially
>in the large background tree in the middle.

I was wondering how the grill cloths looked so good. Excellent work. POV-Ray
always forces us to compromise one thing for another. I've been fighting AA
as well, wanting sharp textures but no obvious stair stepping.

>Overall, I tried to do this without using things like Poser, X-frog,
>pre-built models etc.  Probably because I don't own any of those things. ;-)
>But more to the point, since I don't own those things, I wanted to show
>what's possible using just POV-Ray, and a few other simple, mostly free
>tools.  I think some of the scoring may have taken that into account, but
>that's just my feeling.

I also like to use POV-Ray only, partly because I'd like to learn what it
can do. Once I think I've learned how to use its many tools, then I'll
branch out to add/use others. Or maybe just buy Maya!

>Finally, I'd like to thank my wife, Angela (aka Mrs. Dolt), for supporting
>me on this.  It can get lonely coming home from work and spending the next 5
>hours working on an IRTC entry.  Lonely for both of us.  That may be why
>Gena's "Lonliness" entry had such an impact on so many.

Congrats on your hard work well rewarded. I'm looking forward to retirement
when I can play with POV-Ray all day!

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Slashdolt wrote:
> 
> I think I understand what you are saying.  For future reference, how would
> you recommend correcting that?  Should I make the sun brighter by saying
> something like "rgb <3,3,3>"?
> 
> Also, I set radiosity's "brightness" to 0.3, which may have made everything
> appear darker.

It does not make sense to give precise values for any of these aspects -
it's all a matter of relations between different values.  There have been
various methods posted in these newgroups for realistic lighting setup in
the past.

Concerning radiosity - everything except 'brightness 1.0' is not realistic
but this does not mean that it isn't useful to use different values under
certain circumstances.  You just should know what you are doing.

Christoph

-- 
POV-Ray tutorials, include files, Sim-POV,
HCR-Edit and more: http://www.tu-bs.de/~y0013390/
Last updated 28 Feb. 2003 _____./\/^>_*_<^\/\.______

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On Thu, 27 Mar 2003 09:13:14 -0600, Slashdolt wrote:

>> One of the nicest things about this image (that I failed to mention in
>> the comments file) is the farm in the background. So many of the Old
>Technology
>> entries had objects with very little background. Of course we all know
>> the reason for this: even objects in the background require a lot of
>> work to look good, and there's a time limit on this competition. But
>> the farm, fields, hills, and sky in this image make a great
>> environment. Jeremy obviously spent a lot of time on them.
> 
> I've had mixed feelings about the farm myself.  But since I live in an
> area surrounded by farms, it was an easy place to get inspiration.  I
> would slowly drive by silos on my way home from work.  Many of them are
> rusty, which gives them much more character.  I hope to do a farm scene
> some day. Or perhaps several scenes.
> 
> 
> 

I think the farm is a really nice touch, perhaps because I also live in an
area with many farms (I'm from Iowa).  The rusty tops on the silos are
perfect, and if the windmill is a bit rickety, well... you often see them
in worse shape than that! Also, if you spend much time driving on the
smaller highways in the midwestern U.S., you will see a lot of these
little rural cemeteries--most of them aren't full of radios, though.  :)

It's one good detail in many in this image.

	-Ed

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Renderdog wrote:
>
>I read somewhere that normal daylight is <1.0, 0.84, 0.57>*7.6  Of course
>evening light would be considerably lower, maybe closer to *3.0
>
>When I use really high values for sunlight, the light washes out surfaces
>toward white, losing detail. I guess that's similar to what a camera does,
>but I'm not necessarily trying to duplicate a camera view. On the Innocent
>Shadow image I had to be careful not to wash out the sidewalk's texture
>with too bright a sunlight (though maybe I should've sacrificed that detail
>for realism?).


That reminds me of something I *think* I've noticed, but keep forgetting to
ask...
Is there a difference in the way POV handles light color between using a
higher rgb value or using fade_power to force it higher?

When I use for sunlight something like rgb <1,.85,.6> with a fade_power of 7
it seems like the washing out to white you describe is less noticable, and
surfaces seem to show more of the light color than if I use rgb
<1,.85,.6>*7.

Is that just my eyes going bad with age, or does this actually give
different results?

RG - my 32 bit color is slowly fading to 255 shades of gray

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I've posted Radio Graves after being modified with HCREdit, in p.b.i.

--
Slash

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Slashdolt wrote:
>I've posted Radio Graves after being modified with HCREdit, in p.b.i.

I like it even better. What do you think about it?

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>
> I like it even better. What do you think about it?
>

I'm not sure.  Some things look more washed out.  Chris is obviously right
about the realism, though.

Even if I re-rendered with a brighter sun, I'd probably want to re-work some
of the textures at this point, which would start a whole new project.  Had I
known enough to create it like that from scratch, I probably would have done
so, but I didn't.  Live and learn.

I might adjust the image to make it less dark for the Zazzle poster, though.
Please see my post in p.o-t.  If you (or anyone else) have any suggestions
for the poster, let me know.

--
Slash

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