Hello people

I would need some critics and probably tips to finish my projects
So after struggling with softimage for 2 days, and reading posts from XSIbase i finally achieved somewhat good results for a diamond.
I used the dffraction shader and thx god for Maximus who provided the render tree setup in his shader presets (ure awesome dude ) I was able to get some decent results. For the silver material which is still not tuned, I used architectural material and bumped the ior to 2,full reflection.
I got the photometric lights from wombat and a HDRI plugged in the environement,FG on (Raytype switch with one texture for reflection/refraction..and the other for FG)
My setup is linear, basically gamma 2.2 but I also render to gamma 2.2,I find it easier then tweaking exposure in PS.(No mia_photometric exposure)
Also added a bit of glare.

My concern is,the overall look is a bit washed, and the diamonds doesn't seem to have enough contrast,they look like plastic (especially the smaller ones on the side). I would be able to tweak it in PS, but as far as it goes for SI, what else can i do to get better results.

Two ideas I had, 1st is I'd use a higher resolution reflection map - the convex shape magnifies the map and this shows the blurry low res quality, which makes the ring material look plastic like.
2nd idea is to make sure all specular and diffuse is off in the materials.
About the reflection map, I'm not even sure if you use one, but generally more contrast/sharpness in the environment would be better.

Here's a couple thoughts that might help. I'm not a pro jeweler or jewelry photographer so take it with a grain of salt.

You might want to leave off FG altogether since in this case you don't need color bleeding and all it will do is reduce your contrast and "wash it out". With a very reflective surface like this it may not be what you want.

You'll probably need some strategically placed black cards to get the highlights you want, it looks like maybe you have a lot of white and gray in the environment. Take a look at some photo studio setups used for this purpose, that may help.

Just wondering, IOR of 2 on the silver material? Not sure what the reason for that would be although with no transparency, it should make no difference.

One last thing, the holes or indentations the diamonds are set in may have a big impact on their look. Maybe check how they are actually set in real life. The shape and color of the holes would make a difference I think.

Keep going

juste to reply about the IOR stuff...
In fact Architectural shader and his IOR property play also on the look of a metal shader. For this you need to check IOF on the fresnel.

But in this case i would have put 20 in IOR not 2 ;-)

ActionArt has a point.

I did a job once with diamonds/pretty shiny rocks, and ended up having a separate piece of geometry under the diamond as a casing.
Making this white helped a lot bringing over the feel of the refractions inside te diamonds.

And of course lighting and bounce cards will help a lot too. Search the web for studio setups for photograping chrome/reflective objects, that might help getting the look more towards the examples you posted.

rob

Hey, take a look here

http://www.tabletopstudio.com/jewelry_photography.html

and try to recreate this in 3d, i usually found lots of tehcniques there really interesting and great for product shots.
Hope that helps, that website has a lot of info for a lot of product shots.
Another thing that might help is i always use the mip_matteshadow shader for the ground, make it fully white or black depends on the plate you want and use some catch reflections. have the ambient occlusion option too. Really handy for this.

Max

yes, that's the one.

they also have some tips for glassy stuff: http://www.tabletopstudio.com/documents/glass_photography.htm

rob

Zap Andersson wrote a blog post about rendering diamonds with mental ray:

http://mentalraytips.blogspot.ca/2009/11/fire-and-ice-rendering-diamonds-and.html

Awesome stuff guys,thx a lot for help now I have work to do lol
The tabletop studio website is so nice, I overlooked that aspect, anyways one last thing if I can ask,probably its a noob question,but how would I go and diffuse the light, like they explain on the site, I know that you can use pannels/diffusers, but that method looks different from what I see..

@grahamef, thx man Ive already been there, but I had to rely mostly on the XSIbase thread, since in SI its always more complex doing things

i did this time ago, but wanted just to point out that what makes gems shine are the reflections, dont forget you have the post effects too, so you might gonna pump the effect in ps.



this is maxwell with no post btw, since i had on an old folder i posted it.
Scene setup was just 2 panels, i know its far from perfect but wanted to just point out the shiny/panels reflections.

Hope i've been of some help

Max