A simple comparison of the two.

...Chambers

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Yes, that is interesting. I think the use of specular or phong depends on 
the type of material one wants to render (apart from personal preferences of 
course). For really shiny objects I tend to use phong, while for just 
smooth, subdued reflections (waxed wood for instance) I tend to prefer 
specular. I very seldomly mix the two together.

Thomas

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Interesting example, but are you sure you're using equivalent values of 
roughness and phong_size? on the top 2 it looks like you've got a much 
smaller phong highlight than specular. I generally reckon phong_size 50 is 
equivalent to roughness 1/50.

One thing I've noticed about specular is it gets a hard line through it when 
you're using large highlights with rim lighting (i.e. lightsource behind the 
object). In this picture specular's on the left and phong's on the right. In 
this situation specular looks completely unrealistic IMO.

-- 
Tek
http://evilsuperbrain.com

"Ben Chambers" <ben### [at] pacificwebguycom> wrote in message 
news:45e514a9@news.povray.org...
>A simple comparison of the two.
>
> ...Chambers
>

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Tek wrote:
> Interesting example, but are you sure you're using equivalent values of 
> roughness and phong_size? on the top 2 it looks like you've got a much 
> smaller phong highlight than specular. I generally reckon phong_size 50 is 
> equivalent to roughness 1/50.

The top two use default values.  For the bottom two, I adjusted the 
values to make the highlights approximately the same size.


> One thing I've noticed about specular is it gets a hard line through it when 
> you're using large highlights with rim lighting (i.e. lightsource behind the 
> object). In this picture specular's on the left and phong's on the right. In 
> this situation specular looks completely unrealistic IMO.


This is because specular highlights are much stronger near the horizon. 
  Unfortunately, the highlight overlaps the shadow line.  You can 
overcome this by using an area light, of course.  The  phong looks 
better because the highlight is smaller, fading out before it hits the 
shadow line.

...Chambers

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