I like your purist attitude, but I don't have the patience to wait 8 hours
each time I make a change, nor am I good enough to do it right the first
time (first 10 times?). In any case, I'm finding out that multiple passes
are kind of fun--I like the control that it offeres.

"Timothy R. Cook" <tim### [at] scifi-fantasycom> wrote in message
news:3BECCD86.E534895D@scifi-fantasy.com...
> Jack wrote:
> > Anyway, here's the result of the effort so far--still a bit to
> > finish: stove, microwave, windows, etc--but comments welcome
> > (about the image or rendering in passes).
>
> I like the microwave as-is; you put the food in, it cooks it.
> None of that plunking about with figuring out how long, the
> microwave already knows...;)
>
> As far as rendering in passes...it takes away from the idea of
> doing the whole image with one program, with one pass.  That's
> my motto...'one program, one pass'...eventually there'll
> actually be software that can do that, with any scene at all.
>
> --
> Tim Cook
> http://empyrean.scifi-fantasy.com
>
> -----BEGIN GEEK CODE BLOCK-----
> Version: 3.12
> GFA dpu- s: a?-- C++(++++) U P? L E--- W++(+++)>$
> N++ o? K- w(+) O? M-(--) V? PS+(+++) PE(--) Y(--)
> PGP-(--) t* 5++>+++++ X+ R* tv+ b++(+++) DI
> D++(---) G(++) e*>++ h+ !r--- !y--
> ------END GEEK CODE BLOCK------

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I agree the lighting looks fake--it is.

I'm open to suggestions on how to improve it--I'm just a beginner at this
pov stuff. In fact, this is my first radiosity image. What do you suggest?

Here's the settings now:
for the radiosity pass, I have one spot light on the floor pointing to the
ceiling, with these radiosity settings:
  pretrace_start 0.08
  pretrace_end   0.005
  count 100
  nearest_count 10
  error_bound 0.1
  recursion_limit 10
  low_error_factor .01
  gray_threshold 0
  minimum_reuse 0.001
  brightness 2
  adc_bailout 0.01/2
  max_sample 1.5

the shadow pass is a point light near the ceiling in the center, and the
sunlight pass is a spot shining through the window (out of view).

John

"Xplo Eristotle" <inq### [at] unforgettablecom> wrote in message
news:3BECFDA7.2872429E@unforgettable.com...
> Jack wrote:
> >
> > Anyway, here's the result of the effort so far--still a bit too finish:
> > stove, microwave, windows, etc--but comments welcome (about the image or
> > rendering in passes).  This image was done in 3 passes: radiosity pass
(8 hr
> > render time), shadow pass (5 minutes) and sunlight pass (2 minutes). The
> > image was then put together in GIMP.
>
> I have to say that the lighting looks rather fake to me.. except in the
> spot where the sunlight hits the counter, that looks really good (huh?
> go figure).
>
> -Xplo

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Can you explain how you got POV to separate the shadows, radiosity, etc.
into separate images?

Did you use alpha output?

John Haiducek

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Source images were bmp output from pov.
I'm not a graphics expert--you're out of my league in this area--but here's
how I layered the image:
shadows -- multiply, transparancy 51, added a little blur
sunlight -- addition, transparancy 61, added a little blur

GIMP is free, what can I say?


"Kari Kivisalo" <ray### [at] engineercom> wrote in message
news:3BED56CD.80884840@engineer.com...
>
> Is there additive layer mode in Gimp? Can it display real time
> gamma corrected preview when layers are edited. Can it do this
> for 48 bit images?
>
> These are the requirements for high quality composites of
> different light contributions. Because the source images
> must be linear, 24 bits doesn't leave much room for editing.
>
> Were the source images linear?
>
> _____________
> Kari Kivisalo

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Here you go:

http://members.tripod.com/johnkbradshaw/pov/pov.html


"Steve" <ste### [at] zeroppsuklinuxnet> wrote in message
news:slr### [at] zero-ppslocaldomain...
> On Sat, 10 Nov 2001 00:38:21 -0500, Jack wrote:
> >After reading a couple chapters of Jeremy Birn's Digital Lighting &
> >Rendering, I decided to try rendering in passes (radiosity pass, shadow
> >pass, etc). Saves a lot of time and I can make slight adjustments with
more
> >control, i.e. adjusting the darkness of the shadows.
> >
> >Anyway, here's the result of the effort so far--still a bit too finish:
> >stove, microwave, windows, etc--but comments welcome (about the image or
> >rendering in passes).  This image was done in 3 passes: radiosity pass (8
hr
> >render time), shadow pass (5 minutes) and sunlight pass (2 minutes). The
> >image was then put together in GIMP.
>
> I'd never use the dishwasher, too many buttons.
>
> The rendering in passes idea is interesting, have you got a web space
where
> you can put all three images so that we can have a closer look?
>
> --
> Cheers
> Steve              email mailto:ste### [at] zeroppsuklinuxnet
>
> %HAV-A-NICEDAY Error not enough coffee  0 pps.
>
> web http://www.zeropps.uklinux.net/
>
> or  http://start.at/zero-pps
>
>   2:22pm  up 33 days,  6:05,  1 user,  load average: 1.01, 1.03, 1.00

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The radiosity pass is normal, the shadows pass I did by using negative
illumination, then layering as multiply (color burn), the sunlight was just
a normal image with one spotlight and ambient light set to zero--this was
layered as addition.

I also used a little bit of blur on the shadows pass and the sunlight pass
and adjusted the transparency. Heres the link to the images if you want to
see:
http://members.tripod.com/johnkbradshaw/pov/pov.html


"John David Haiducek" <jha### [at] enginumichedu> wrote in message
news:Pin### [at] azureenginumichedu...
> Can you explain how you got POV to separate the shadows, radiosity, etc.
> into separate images?
>
> Did you use alpha output?
>
> John Haiducek
>
>

Post a reply to this message

Jack wrote:
> I like your purist attitude, but I don't have the patience to wait
> 8 hours each time I make a change, nor am I good enough to do it
> right the first time (first 10 times?).

Hmm...I use mosaic preview, so usually let it do only a few passes
before hitting 'cancel' and changing what I need to change...
More than that, the 3d camera view in Moray is a primary preview
of what the scene will be set up as (will you people hurry up and
finish POV 3.5 so Lutz can release a supportive version of Moray?).

However, I'm currently on day 3 of what amounts to a test render,
just to see what my WIP looks like with media as the materials.
-- 
Tim Cook
http://empyrean.scifi-fantasy.com

-----BEGIN GEEK CODE BLOCK-----
Version: 3.12
GFA dpu- s: a?-- C++(++++) U P? L E--- W++(+++)>$
N++ o? K- w(+) O? M-(--) V? PS+(+++) PE(--) Y(--)
PGP-(--) t* 5++>+++++ X+ R* tv+ b++(+++) DI
D++(---) G(++) e*>++ h+ !r--- !y--
------END GEEK CODE BLOCK------

Post a reply to this message

Jack wrote:

> Anyway, here's the result of the effort so far--still a bit too finish:

Well, it looks like the handles are floating. There's a little to do with the
lighting I think. But then there's also their positioning. If you look at the
pair of doors to the left of the dishwasher, then the pair of doors under the
sink, you'll see that one set is shifted to the right, while the other is
shifted to the left. That comes out as the parralax effect you'd get if they
were hovering an inch or so in front of the doors, instead of on them.

--
Jon A. Cruz
http://www.geocities.com/joncruz/action.html

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Jack wrote:
>
> shadows -- multiply, transparancy 51, added a little blur
> sunlight -- addition, transparancy 61, added a little blur

Sounds right but when doing these kind of composites the source
images must not be gamma corrected. POV-Ray outputs linear samples
(not corrected) when assumed_gamma is not set. Gamma is applied
to the final composite. The reason for this is that
(a+b)^c != a^c+b^c.

Default radiosity brightness is the correct one so no need to
touch that.

So, Gimp has additive layer mode which is missing in Photoshop.
If the new version runs longer than 5 minutes without crashing
I'm going to find out if it can do gamma preview :)

The Hollywood Gimp would be ideal for this kind of work but there
is no windows version.

_____________
Kari Kivisalo

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All the images were assumed_gamma 1.0

(a+b)^c != a^c+b^c ?   The math I get, but I don't understand how this
relates to compositing. c=gamma correction? Is this the reason why gamma
should be 1?

After Jon's post I looked at Hollywood GIMP. Didn't see anywhere to download
anything. As for no windows version, I've been wanting to use linux more
often. This may be a good excuse.


"Kari Kivisalo" <ray### [at] engineercom> wrote in message
news:3BEDC3AD.11E3B798@engineer.com...
> Jack wrote:
> >
> > shadows -- multiply, transparancy 51, added a little blur
> > sunlight -- addition, transparancy 61, added a little blur
>
> Sounds right but when doing these kind of composites the source
> images must not be gamma corrected. POV-Ray outputs linear samples
> (not corrected) when assumed_gamma is not set. Gamma is applied
> to the final composite. The reason for this is that
> (a+b)^c != a^c+b^c.
>
> Default radiosity brightness is the correct one so no need to
> touch that.
>
> So, Gimp has additive layer mode which is missing in Photoshop.
> If the new version runs longer than 5 minutes without crashing
> I'm going to find out if it can do gamma preview :)
>
> The Hollywood Gimp would be ideal for this kind of work but there
> is no windows version.
>
> _____________
> Kari Kivisalo

Post a reply to this message