Gems and their reflections + background color gradient issues

i am having isues with gems, do i need to make the reflective color white or the same color as the gem? also the background color gradient i made is having a color issue that looks like jpg artifacts, especially around the gems.

raining gems.blend (1.25 MB)

can you tell us what you expect or wnat to achieve as a render ?

happy cycles

i want to achieve a more realistic gem material by finding out if it should reflect white or reflect the same color as he gem, and i also want to get the background color gradient, to be more smooth instead of looking like it has a low color depth, and last, if you look at the gems over the background color gradient, you can see a black rim around them, i want to get rid of that too.

more realist in what ways ?
i mean this is a relatively dark scene so not much reflections available

there are ways to get more cautics but in this case there are no objects to show it
and may be with some composite it is possible to get more halos/flares around the gem

so can you elaborate on what specific effects you want to see!

happy cycles

in the rendering scene compositing, i used a is glossy ray node, so the gems are reflecting a forest scene, but the background is still black. i did add a blur for a glare effect to the gems. and as for realism, i just want the gems materials to look more like real gems.

if you could set up a realistic gem material for me and send it through in the original .blend atachment, i could examine it and learn from that, that is mostly how i learned what i know today.

sorry is this in cycles ?
did not check file first have to understand what you want

did you check for instance some of the gems at blenswap
might give some ideas may be!

happy cycles

yes it is in cycles

there are several renders of gems at blendswap

download the one you want and then we might continue discussion may be!

happy cycles

ok so here is my favorite, one thing though, i cant understand why the material is set up the way it is, if you wouldnt mind could you explain how this material was set up (for the diamond) and what everything does.

sorry forgot to upload

can you give the link!


the le aleady contains some basic explanations

go to the scripting window and you’ll find some doc there

this diamonds are sort of faking light dispersion which cannot be done right now in cycles!

These diamonds have materials attached that fake the dispersion of diamond, so that colours separate as they pass through. This is done with material nodes in cycles.

now don’t forget here that the light set up is done for a very dark scene to emphesize the colors from the diamonds
this may not work well if you increase the light intensity!

hope it helps

happy cycles

i did find a great and easy setup, red green and blue glass, at diffrent iors, added together, make a clear dispersive material, and with a colored class mixed into the bottom node of a mix shader, and a is refractive ray node in the fac, i can create colored, dispersive materials. but there is still the problem of the background

show us some pics

happy bl

after hours of experimenting, i found out the png color depth was too low. and i experimented with the gem material, and created a reflection color gradient using a gradient texture, connected to a color ramp, mixed with the original crystal shader, and controlled by an ig glossy ray node.

the only thing is, i want to be able to change the overall gem color without effecting the reflective color gradient. it is using the color in the mioddle of the color ramp for the overall gem. how can i give the gem a custom overall color, maybe clear?
Realistic Daimond Material.blend (695 KB)

the ramp color on the glossy node seems to strongly affect the overall color
so would be difficult to change that one without removing it !
but also don’t forget your changing the color in the composite too

try it with another set up where you can have more control color may be!

happy cycles

You could use a mix shader mixing a Refraction node (coloured whatever colour you want your gem) and a glossy node that is the colour you want your reflections (e.g. white or a gradient).

You could even plug the fresnel node into the fac slot of the mix shader to give stronger reflections at glancing angles and more transparent lookign straight on (something that is observed in real life)