Sphere Light Studies

miguelnarayan

Hello here is my latest light study homework, I can't spot any mistakes myself, besides maybe some sloppiness on the cast shadow on the ground? But I think the overall point is there? I saw a gradual increase in quality from the top to the bottom, as they were born... but I'm not an expert, and someone told me I should invest my time in color and light and improve my painting skills from now on instead of drawing. so C&C welcome. Have a good day!

Muzzoid

Saturated colours won't drop saturation as they get brighter unless over exposed. It should look more like this.

miguelnarayan

Thank you, I will keep at it

RN

It's not just a light study, it's also a material study. How rough and porous a surface is will influence how it reflects light. Other properties like having a thin film of varnish or oil will also affect it (because of interference).

What are those spheres made of, and what lighting conditions are they under (like what kind of lamps or light sources)?
If they are all of the same material then you can do something like just paint one with a lot of care to make it look good, then duplicate and change the hue to make the others. The falloff of light should be exactly the same.

This is a Blender render with different materials.


I like to look at these for inspiration:
- http://polycount.com/discussion/141023/material-studies
- http://vesner.deviantart.com/art/100-texture-studies-360570335

Muzzoid

Hmm, man i'd say that he needs to learn how to render diffuse colour simple materials before he even begins to think about things like fresnel, metallic specular and interference.

You start with the simple case, nail it, then move on.

RN

There's an article explaining what a 'diffuse surface' (or material) means:
https://en.wikipedia.org/wiki/Diffuse_reflection

And the classic: http://www.huevaluechroma.com/021.php

Muzzoid

Yep hue value chroma is the shit. If you can understand it that is. Seems most 2d guys are alergic to reading sadly.

nissa23

Nice...
Thanks, I will keep at it.

miguelnarayan

Some more light studies. And I'm truly sorry for saying this, I really don't disagree with people over the internet, it always tends to be taken the wrong way, but I do not agree with you, it was not the principle that I was taught, @Muzz, the saturation may not directly drop, but the color of the light plays it's role, shifting the saturation, hue and value of the object it interacts with, mostly it's highlight and mass light part of the object.
The first study was not a material study. But thank you for taking the time to commenting on my thread.

Muzzoid

You can say you disagree with me, but it's just not how the physics works out. Full disclaimer, i program a tool that pretty much does nothing but make coloured spheres for generating light based colour palletes called colour constructor, so we can get into the maths if you want.

The saturation drop you are seeing is not diffuse light, it is specular light, and you need to wrap your head around this before you can grasp materials. Also metal has totally different physics from non metal. http://www.webexhibits.org/causesofcolor/9.html
You should also read up on exposure and how it works with cameras.
Just curious, what resources have you been reading?

RN

Hi. I like those last spheres, they give a lot more sense of depth.
A couple of things I'd do different:

- Add penumbra to all shadows. Example below with the skin material done crappily with mouse, and it's wrong after I look at it again: the smudging should always go 'in' to the shadow; the penumbra never goes outside of the shadow, it smooths from the edge to the inside.

- The gummy bear material is translucent. 'Transmission' is one of the three behaviours that matter has with light. The other two are 'absorption' and 'reflection'. The core of the sphere is more dense and so less light from the bakcground passes through it (reference).

miguelnarayan

Thanks @RN - well pointed out on the shadows, to be honest, I did not pay too much attention to them, but it's a very pertinent detail to them. I was just focusing more on color and light. You're also right about the gummy bear, I noticed it's shadow error shortly after I closed the homework and posted it here. I've fixed it, adding it's color to the shadow zone.

@Muzz I have been basing myself off CGMA - Art of Color and Light with Ryan Lang, just look up cgma color and light homework and you'll see some examples of similar homework of other people, for that class. I'm not sure about it's math, I may have to place a ball in a shadow box and draw from life to really get to it. Thanks

splicer

These are cool. Are you going to apply any of these to a future drawing?

miguelnarayan

It's my intention to break down the material in these sphere templates in a quick form, to then apply to my paintings, someone commented on my work recently saying there is no evidence of variety in my brush strokes that suggest different materials and their reflections, I guess this is the first milestone to fix it.