[seghier]

test with black and white hdr refraction
i modify the blue color of the gem

[Half Life]

I'll just chime in to specifically address your question and say that I think getting HDRLight Studio is probably the thing that might help you the most... I mean, it is designed specifically for quickly experimenting with lighting for product renders -- and that would be the thing that is probably the biggest issue I'm seeing.

Here is a version of your MXS file -- I adjusted the materials slightly, got rid of your lighting (I used HDRLight Studio to bake up a replacement environmental EXR, which is included in the zip file), and tweaked your camera... mostly I was using your photo (from a few posts back) as a guide, though the model you provided is much more simplistic than the ring in the photo (and that has a big impact).

Here is a version with a bit of simulens and levels/curves adjustement:


I am not a jewelry rendering pro (I don't even like jewelery much) -- nor even a product rendering guy. So the fact that I (who basically knows nothing) can get a somewhat respectable result in a few minutes of playing should be encouraging to you, who does already have that refined taste and eye for what would look best for your specialty market. Once you have HDRLight Studio you can play with the lighting endlessly until you have exactly the results you want... honestly everything else is pretty simple as far as Maxwell is concerned, and you already have a ton of good advice about that in this thread from seghier.

Best,
Jason.

[seghier]

thank you Jason; as you say the shape need remodeling and we can see small black triangle and need to fix that with rhino
i create a new shape with blender yesterday to test the render
also i modify the gold material ; i am not sure if it is true and real but it give better result than the original material
the original :
Layer : Silver w=27 ; Copper w=14 ; Gold w=58 / Roughness = 1
the modified material :
Layer1 : Copper w=100 ; opacity mask=14 / Roughness = 1
Layer2 : Silver w=100 ; opacity mask=27 / Roughness = 1
Layer3: Goldr w=100 ; opacity mask=58 / Roughness = 5
i will post the new render when finished

[emarvets]

Thanks you Jason. You got the result from the diamonds I was trying for. I will purchase HDR Light Studio and study your EXR.

I know my model is simple compared to the actual. It does not take into account hand set bezel and polishing. Also, I don't have a bump map for micro scratches and the band texture. It's one mesh, so I think I need to learn UV mapping. I think 3D Coat will do this.

segheir, I was able to use render channels to make a composite image. I can expose the background and model separately. Thank you.

I also spent a good deal of time working the with IBL Refractions channel to light the diamonds separately with no success. There is not a lot of information I could find online to help. Can you post the MXS with pack and go? I'll try your new gold material as well. As for the aqua, the stone looks better, but the aqua material I built looks like one in real life. That's just the stone.

[seghier]

here the render ; it not finished (dispersion disabled)



and the mxs file:
https://docs.google.com/file/d/0BxZUcGu ... QxQ2JzT3c/

[seghier]

why you want add scratch ?
you find many textures in the web and you can use bump for the gold and the same texture for roughness
you can use differents bump for each layer with different value ; scale ; position and channels
test that using simple plane to get the best result than apply thd material to your ring
for the blue stone try Sapphire

[seghier]

Here new test with dispersion ; i use Google nik collection to reduce noise and apply some filters

[emarvets]

segheir, those are the best looking diamonds yet. Is that the same MXS you posted earlier, just with corrections in Google Nik?

[seghier]

yes this render from the same mxs
with dispertion enabled ; i use nik collection to reduce noise and correct contrast than i try some filters and finaly i add small stars with photoshop
in the scene just play with multilight
retouch of the final renders is very important

[eric nixon]

Seghier, in that last image the gold ring looks like gold glass? its still a nice image though...

I havent rendered any jewelery yet, but I think the trick to getting a lit background (diffuse material) is to use a point source of light (a small bulb) positioned above and behind the subject, and not too near. For lighting the diamond I would use fire and move some emitter planes around behind the camera. HDR lightstudio is also quite suitable, but a bit too much 'cg' for my taste.

If you can find a good hdr ( I can recommed one - 'hdri_furnished-apartment' by cgsource - 10 euros) I would try with that because it will give a more natural result, at the expense of flexibility. 'good hdr' are very rare, prob around 0.2 % of hdr are 'good' i.e. correct light levels with a huge exposure range and massive resolution. Bear this in mind when dealing wirth hdr. A free one with correct exposure is ennis.exr, but it doesnt have enough point sources of light (to give sparkle) and also it doesnt have very big resolution.

I think the best advice in this thread is to 'study photography' but I would interpret that as thinking about light behaviour (depending on point sources or planes) in regard to diffuse and specular surfaces. maxwell doesnt have lenses to focus the light (yet) but you get the same effect by moving a point source further away. (if you need a spotlight, put that emmitter in a black tube)

Also it makes sense to position emitter planes facing towards the subject.

[seghier]

thank you eric
i think it is the effect of left light in the scene . you can see the setup in the mxs file

[eric nixon]

Okay seghier, I opened the mxs, your material is transparent because the base layer weight is only 58%. The base layer must be 100%.

[seghier]

thank you eric . it's good to you modify the material fo better result
i will fix it

[eric nixon]

Also, you can always put a pure black base layer if you just need to keep the material opaque.

[Mihai]

Seghier, I really like the green ring one. Kind of heavy on the noise reduction though, I understand you're rendering these on only a laptop?