This was an engineering examination test piece. (A real life example
of required sharp edges ;) It has no other useful purpose*

Couple of days on the csg, mostly on the helix thread.
Weeks on the brass texture which still doesn't look right.
Bright sun-light on the left.
Objects in the room don't show very well despite brass reflection of
0.6 but they DO s****up the brass texture.

An 800*600 98k version is here:
http://www.peake42.freeserve.co.uk/pix1/tape.jpg

* Red Tape:
*Needlessly time-consuming procedure.
*The tape used in public offices for tying up documents, etc.; hence,
official formality and delay.
*The collection or sequence of forms and procedures required to gain
bureaucratic approval for something, especially when oppressively
complex and time-consuming.

--
Alf

http://www.peake42.freeserve.co.uk/
http://www.qsl.net/gw3srg/

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Attachments:
Download 'tape0.jpg' (40 KB)

Preview of image 'tape0.jpg'

Alf Peake wrote:
>
> Weeks on the brass texture which still doesn't look right.
> Bright sun-light on the left.
> Objects in the room don't show very well despite brass reflection of
> 0.6 but they DO s****up the brass texture.

Shiny metal gets most of its appearance from reflection, not diffuse 
lighting. Try cranking the diffuse down to 0 and slowly increasing it 
from there until it looks good.. also, from what I can see here, you 
need a much stronger specular to simulate the reflection from strong 
sunlight. You might even consider using photons for the reflective caustics.

-Xplo

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I have had pretty good luck with metals by bringing the total luminosity of
the pigment way down and then using a relatively high reflection value.  See
my previously posted image.  Xplo is right ... you need to have it
reflecting something to make much of the effect.

Aaron


"Xplo Eristotle" <xpl### [at] infomagicnet> wrote in message
news:3fa6aa25@news.povray.org...
> Alf Peake wrote:
> >
> > Weeks on the brass texture which still doesn't look right.
> > Bright sun-light on the left.
> > Objects in the room don't show very well despite brass reflection of
> > 0.6 but they DO s****up the brass texture.
>
> Shiny metal gets most of its appearance from reflection, not diffuse
> lighting. Try cranking the diffuse down to 0 and slowly increasing it
> from there until it looks good.. also, from what I can see here, you
> need a much stronger specular to simulate the reflection from strong
> sunlight. You might even consider using photons for the reflective
caustics.
>
> -Xplo
>

Post a reply to this message

"Xplo Eristotle" <xpl### [at] infomagicnet> wrote in message
news:3fa6aa25@news.povray.org...
>
> Shiny metal gets most of its appearance from reflection, not diffuse
> lighting. Try cranking the diffuse down to 0 and slowly increasing
it
> from there until it looks good.. also, from what I can see here, you

I'll try that again. This was my final brass texture.

texture{
   pigment{ rgb <1,0.9,0.35> }
   finish {
      ambient 0.2 // 0.1
      diffuse 0.6 // 0.2
      brilliance 4
      metallic
      specular 0.7 roughness 1/1000
      reflection{ 0.1, 0.6 metallic }
      conserve_energy
   }
}

> need a much stronger specular to simulate the reflection from strong
> sunlight. You might even consider using photons for the reflective
caustics.

I used photons but they are not very visible.

Thanks for advice

Alf

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"Aaron Gillies" <no### [at] spamcom> wrote in message
news:3fa6aacf@news.povray.org...
> I have had pretty good luck with metals by bringing the total
luminosity of
> the pigment way down and then using a relatively high reflection
value.  See
> my previously posted image.

Your metal around the barrel looks very good.

> Xplo is right ... you need to have it
> reflecting something to make much of the effect.

Yes. The object is in a fairly "busy" room (fire, chairs, wall
pictures, TV, doors etc) but I think most of the reflections are of
the ceiling.

I'll play with it a little longer.

Thanks

Alf

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Try an HDRI environment!

"Alf Peake" <alf### [at] peake42freeservecouk> wrote in message
news:3fa518dc@news.povray.org...
> This was an engineering examination test piece. (A real life example
> of required sharp edges ;) It has no other useful purpose*
>
> Couple of days on the csg, mostly on the helix thread.
> Weeks on the brass texture which still doesn't look right.
> Bright sun-light on the left.
> Objects in the room don't show very well despite brass reflection of
> 0.6 but they DO s****up the brass texture.
>
> An 800*600 98k version is here:
> http://www.peake42.freeserve.co.uk/pix1/tape.jpg
>
> * Red Tape:
> *Needlessly time-consuming procedure.
> *The tape used in public offices for tying up documents, etc.; hence,
> official formality and delay.
> *The collection or sequence of forms and procedures required to gain
> bureaucratic approval for something, especially when oppressively
> complex and time-consuming.
>
> --
> Alf
>
> http://www.peake42.freeserve.co.uk/
> http://www.qsl.net/gw3srg/
>
>
>

Post a reply to this message

"Harold" <bai### [at] 3dculturecom> wrote in message
news:3fa928d9$1@news.povray.org...
>
> Try an HDRI environment!

Yes, its on my "to try" list which is now long enough to reach the
moon :/
Some of the results I've seen posted here in p.b.i are amazing.

I've taken Xplo and Aaron's advice and the updated scene does look
better:
>> An 800*600 98k version is here:
>> http://www.peake42.freeserve.co.uk/pix1/tape.jpg


Alf

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On Mon, 3 Nov 2003 21:26:53 -0000, "Alf Peake"
<alf### [at] peake42freeservecouk> wrote:

>"Xplo Eristotle" <xpl### [at] infomagicnet> wrote in message
>news:3fa6aa25@news.povray.org...
>>
>> need a much stronger specular to simulate the reflection from strong
>> sunlight. You might even consider using photons for the reflective
>caustics.
>
>I used photons but they are not very visible.

Photons will show much better if you increase the specular reflection.
Try something like reflection { <0.6, 0.5, 0.2> } (and lower the
diffuse pigment accordingly).


-- 
------------------- Richard Callwood III --------------------
~  U.S. Virgin Islands    ~  USDA zone 11  ~  18.3N, 64.9W  ~
~  eastern Massachusetts  ~  USDA zone 6 (1992-95)          ~
--------------- http://cac.uvi.edu/staff/rc3/ ---------------

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"Richard Callwood III" <ric### [at] yahoocom> wrote in message
news:rntiqv0tl83u3ek8eol2jmbh5dmus0rla6@4ax.com...
> On Mon, 3 Nov 2003 21:26:53 -0000, "Alf Peake"
> <alf### [at] peake42freeservecouk> wrote:
>
> >"Xplo Eristotle" <xpl### [at] infomagicnet> wrote in message
> >news:3fa6aa25@news.povray.org...
> >>
> >> need a much stronger specular to simulate the reflection from
strong
> >> sunlight. You might even consider using photons for the
reflective
> >caustics.
> >
> >I used photons but they are not very visible.
>
> Photons will show much better if you increase the specular
reflection.
> Try something like reflection { <0.6, 0.5, 0.2> } (and lower the
> diffuse pigment accordingly).

I checked the "real life" scene yesterday in bright sun-light on the
wood table. I was surprised that the caustics could not be seen
against the lighter wood unless you looked very hard. I was sure there
should have been some :/

Alf

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