glistening jewels

[dblhelix]

planning stage:

 

what's a smart way to have jewels reflect light?

 

i'll be making crowns, they have different kinds of stones in/on them.

the light won't be that of the sun or lamp, cheats are sort of built in.

i'll be compositing excessively, no problem to add a layer or three.

 

but how to think/plan/execute?

[dblhelix]

miniscule blobbies?

with mirror material reflecting a lamp that only affects them?

that would be ~20 emitters..

[NancyGormezano]

what's a smart way to have jewels reflect light?

 

Can you post an image of something similar as to which effect you are trying to simulate? There are different cheats for different things. If it's a caustic type thing - it's one way (I'm not too good with caustic type stuff)), if it's a "lens flare type thing" it's another. There's also possibly a cheat to get the actual jewel to look jewel like by using matcap shader, and different specular shaders. It's tweaky-deaky time.

 

Blobbies? Having a hard time picturing which effect you are trying to get?

[dblhelix]

caustic sounds wonderful, had to google to see 3D relevance. search gave corrosion and Apex Twin.

choosing that. the film is a Caustic Danse Macabre.

 

Blobbies? Having a hard time picturing which effect you are trying to get?

basically it's a mirror ball thing, as with a diamond turning in sharp light; but i got caught up in the film HomeSlice has on the blobbies tutorial. there's a softness (a bendyness) in the light from those underwater bubbles that supports other ideas in the scene with the crowns. the effect is in essence the difference between a blinking light and a jewel reflecting light:

the jewel reflects a light show. i don't know how to say it in words. a shrunken, rotating mirror ball off focus?

[NancyGormezano]

Caustics is a term used to describe how light looks/gets bent when it goes thru a non-opaque medium, typically used for glass, water effects (my very imprecise definition). To render that effect accurately in A:M, involves probably, perhaps using features that I do not fool with as they have way too long render times for my short attention span. There are others who would know better how to approach this.

 

However if you're looking for some cheatin', lyin', wouldn't-fool-nobody-but-me fast renders - I quickly put together these projects. The first one uses the matcap shader on a "quick dirty simple faceted jewel" for it's ambiant shader, using an image of a saphire (the internet is your friend), & where the specular shader is anistropic. The main Klieg light has a rotoscope (gel) using an image of a diamond, which is creating the sparkly effect on the ground. I also put in a bulb light, positioned within the jewel. The 2nd image is same as first except I turned on lens flare for the bulb light. In the third image, I changed the properties of the lens flare. Unfortunately I didn't save the settings. Well actually, I thought I saved it but - I can't find it.

 

These are to get you started with playing. You would need to use better models, with more facets for your jewels, better images for rotos, better matcap images, better lighting colors, better lensflares, better lighting positioning, etc, etc. tweak tweak tweak. It would also help to have something interesting for the jewels to reflect.

CheatingLyingFAKEJewels.zip

[dblhelix]

worked all day yesterday and today and that's not what i got! decided not to post tests but must admit i'm almost tempted now.. for laughs.. well it wasn't that clear cut in all honesty - i'm using AO almost exclusively (fantasy landscape without sun) and the stones should sparkle as if being the source of the light. the mass of photon destruction surrounding your jewel looks really, really promising, just what i'm hoping for!

 

unfortunately, the chapter beginning "The first one uses the matcap shader" is beyond me, all concepts are new. initiating study mode. thank you so much for the project!

 

found a gem here, cross referencing:

http://www.hash.com/forums/index.php?showt...p;hl=portuguese

[NancyGormezano]

Thanks for your links - they look interesting

 

unfortunately, the chapter beginning "The first one uses the matcap shader" is beyond me,

 

Matcap shader is a plug-in shader for A:M that was developed by the folks at Soulcage (Willi?). Shaders in general are different from materials - (how,why, implementation wise is a mystery to me) - but they only get used if you have turned on use plug-in shaders in the camera data. All plug-in shaders are located at Hash/v16.0 or 15/Shaders and have an extension of .shd. And now that I think about it, I am not sure if Matcap is a standard issue with A:M or if I got it from this forum - so you 1st need to check to see if you have it.

 

To use Matcap, (or any shader) you need to set the shader in the group's properties. Matcap can be used to compute either the diffuse or ambiance "look". Anistropic is used for the specular look.

 

To use Matcap - I find the best/easy predictable results are to set the groups surface diffuse & ambiant color to black, and only use it as an ambiance render shader. (I haven't fooled with it lately, so I could be forgetting something). It usually looks better on models that are more organic, rather that flat surfaces.

 

Do a forum search for Matcap for more detail. Here's a good link, and there is lots of discussion in that sub-forum on shaders in general, as well as Matcap.

 

http://www.hash.com/forums/index.php?s=&am...st&p=328945

 

(It looks like Robcat might be investigating a better way to do jewels)

[robcat2075]

Here's a sample jewel project that J Griffin posted in 2003 using (the then new) caustics

 

JewelsCoverFinal.prj

 

 

I did this render in v10.5

 

 

 

 

the PRJ will load in current version of A:M but the renders don't look quite the same, you would need to investigate some settings mods to get the original look back.

 

 

 

Can anyone tell me why some of the stones are blue in Shaded render even though they are set to be red?

[robcat2075]

messed with the colors a bit

 

[NancyGormezano]

Can anyone tell me why some of the stones are blue in Shaded render even though they are set to be red?

 

That is weird. It is just certain cuts that appear that way - but I can't detect any discernible differences in their properties (just transparency 90% instead of 92%) - It doesn't seem to be related to their position in the chor either. They are modeled differently with respect to origin as well. They also look different if I unembedded them - but still blue (ver 16, 32 bit)

Edited April 4, 2011 by NancyGormezano

[robcat2075]

what's a smart way to have jewels reflect light?

 

basically you want some of the facets to flash at various times?

 

how about making a facet a Group and animating it's color in the chor to a brighter color or white briefly?

[dblhelix]

~intermission~

 

ok been reading about cornell boxes, radiosity, and inverse square law -

i feel like i'm being spanked with roses. enough!

 

caustics is now out, visible impact on environment by light is out. the light behavior i'm looking for is that of a jewel sparkling in an ordinary way, the facets giving off reflections.

going back to AO to torture test one "diamond"=b&w jewel with basic lights. for that to make sense, it seems i have to study rendering.

 

Nancy, that one chapter is so full of information, i don't know how to thank you. even the images of options had some (unintended by you) surprises for the newb.

the reason i mention blobbies is the difference between light playing on a faceted surface and on a bubble in motion.

while it's a gem we see, the softer change in reflected light direction (as off of an underwater bubble) has a dreaminess to it. that would work very nicely here.

 

robcat, the animation by group is another one of your smart workarounds but not doable here; i've 11 stone encrusted crowns, first i thought 8 of them would have jewels sparkling on them but i feel a burst of creativity descending upon that detail in the manuscript. it would be nice if i could get away with... oh drat.. five...?

thanks for that Griffin project!

 

gonna go sit on an icepack and digest.

[robcat2075]

. the light behavior i'm looking for is that of a jewel sparkling in an ordinary way, the facets giving off reflections.

 

I would put a place a bunch of specular-only lights around the scene and let the facets of the jewels catch them.

[dblhelix]

sounds like a perfect place to start! - tomorrow.