the reflectivity of everything
polycounter lvl 18
with my lack of education on light, i've been unable grasp certain characteristics of it when trying to create materials.
i know about specularity, reflectivity, and i have worked something out in my head on how it works. all i need is a "yes you are right" or "no, theres something you're missing, its..."
its basically like this:
the flatter a surface is, the more clarity of reflection it will have.
a rough surface will scatter light in all directions, and hence get a much duller appearance, weaker lightsources simply are not visible in rough surfaces, you need a strong light on the surface for it to show any sort of reflection
(think putting a strong light onto a red beadsheet, to make
the bedsheet "glow" or reflect its colour onto a surface)
the "specular highlight" is a faked lightsource.
another thing i noticed when walking down the street, was that when looking at the street as i was moving towards the sun, the street was so bright it was hard to look at. but when walking away from the sun, the street was its usual dull grey. the same when looking down at the street. dull grey. i think the sun basically reflects itself in the street.
i know about specularity, reflectivity, and i have worked something out in my head on how it works. all i need is a "yes you are right" or "no, theres something you're missing, its..."
its basically like this:
the flatter a surface is, the more clarity of reflection it will have.
a rough surface will scatter light in all directions, and hence get a much duller appearance, weaker lightsources simply are not visible in rough surfaces, you need a strong light on the surface for it to show any sort of reflection
(think putting a strong light onto a red beadsheet, to make
the bedsheet "glow" or reflect its colour onto a surface)
the "specular highlight" is a faked lightsource.
another thing i noticed when walking down the street, was that when looking at the street as i was moving towards the sun, the street was so bright it was hard to look at. but when walking away from the sun, the street was its usual dull grey. the same when looking down at the street. dull grey. i think the sun basically reflects itself in the street.
Replies
thats basically what i've kept in mind.
i just discovered it did the same thing in 3ds max.
i suppose thats why all my reflective objects has been looking so dull :P
a minor test scene i did with a basic direct scanline light.
the scene is the exact same, all i did was change camera position :P
i've been trying to get results like in picture 1 for at least a year now, by increasing the specularity
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"the "specular highlight" is a faked lightsource."
[/ QUOTE ]It's an actual light source highlight, but a faked reflection. In games mapping the environment to shinny surfaces is costly. People look at spec shine and easily forgive it as reflection of light but you need a light source in order for the spec to be noticeable.
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the flatter a surface is, the more clarity of reflection it will have.
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Yes the cavity of the surface plays a roll in the clarity of the image that is reflected back to you. It doesn't make it any less reflective it only effects where those light rays go when they bounce. Some make it to your eye, some are beamed in other directions. Like a broken mirror on the ground the pieces are scattered but they aren't any less reflective then before being broken. Think about a sheet of tin foil fresh off the roll, then crinkle it up a bit. Its not any less reflective it just bounces light at other angles now.
A piece of glass can have a piece of reflective foil on one side turning it into a mirror. Or you can coat both sides in flat black paint and it will have zero reflectivity. Both are perfectly smooth yet one will not reflect light. That same piece of glass can let light pass right though it and depending on your viewing angle it will never reflect anything or it could obscure your view completely.
You're getting there and I applaud your self discoveries. That is a great skill set to have, don't ever lose it or let it go slack. But maybe some reading on how light works would help? Since there are about 5 main properties of light and you've managed to find 1-2 of them.
I could write a book on this subject but I'll hold off since it looks like you want to seek out the answers yourself
Key words to check out: Reflection, Refraction, Scattering, Transmission and absorbsion.
It might also be good to read up on "raytraced lighting" since it works pretty much like natural light.
(1) 3ds max lighting by Nicholas Boughen
(2) Digital lighting and rendering by Jeremy Birn
Among many great sources for CG lighting, these are my favorite.
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(think putting a strong light onto a red beadsheet, to make
the bedsheet "glow" or reflect its colour onto a surface)
the "specular highlight" is a faked lightsource.
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Depending on the strength of the light it will be easy to over power the light rays bouncing off the bedsheet with the overhead light. To make something "glow" like what you want, more defused lighting with the rays set to bounce. You'll also need to turn on "material color effects ray bounce". Cranking up the light won't make the rays bounce and won't give you the glow you're looking for it will only blow out the bedsheet making it pink or white. Bounced lighting does wonders for AO and ambient lighting. It will increase your render times but making pretty takes time...
http://www.itchstudios.com/psg/art_tut.htm#light_stuff
i did an experiment with a flashlight and a bedsheet.
and when talking about a "rough surface" i was thinking about the microscopic roughness, as well as the macroscopic one.
typical of my problems, its usually a fundamental, basic concept that i am unable to grasp, while having no problems with the broader bigger terms.
what i'm trying to do, is unifying my understanding of light into something more manageable, instead of having 30 different concepts of light bouncing around, and not knowing how they interact with eachother.
this has been especially the case with highlights, and reflectivity. it was about a year ago until i realized it was faked reflections of the light source.
and until now i didn't realize that it actually reflected the light source like a mirror would.
its always problematic to get people to help me with the things i'm actually wondering about, 90% of it being poor translation of my visual memory.
oh and thanks for the link, i've already read it though.
heh, i was talking about reality.
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So was I. I was also giving you some practical advice instead of just light theory. Real world lighting bounces but the default settings in Max/Maya do not. The real world has AO, Max/Maya by default do not. It will be hard to achieve some of the effects of real world lighting when they are not active.
Head meet brick wall, careful he plays rough =P