Hi guys,
I’m trying to render an opal gemstone, but I’m failing terribly. My last try was loading a marble material and changing the Map (I attached here the image), which was better than the previous attempts, but still not good.
Is there anybody who can help me to render a convincing opal? I would be very grateful.
Best,
Tati.
Are you looking for a white based opal or gem crystal? From the looks of your image I would guess white based.
Danny
Hi Danny.
You’re right, i’m looking for a white opal, like these: http://lightningridgeinfo.com.au/images/sige-img/opals/white/white-opal-03.jpg
Thanks 
Do you want green and red or from the images all green. I should be able to help you out but it will not be until tomorrow as I am quitting for today.
Danny
It can be green and red. Actually the color doesn’t matter much to me, I really want to know how to make a realistic opal and be able to vary the colors as needed. For me it’s important to understand what are the values which contribute to a good result of the material. I’ve been researching this subject, but found nothing.
That’s perfect, take your time. I really appreciate your time and help 
Tati.
Hi Tati
Pascal recently helped me to figure this out and to achieve convincing result.
here is a screen shot example… if this is good enough for your needs, the steps below is how i did it just in the rhino viewport [being on a Mac i wouldn’t know about VRay but i guess it would be better]
HTH
akash
Many thanks Akash! I found your result very good. I’m gonna follow the steps you taught me 
Best,
Tati.
Hi Danny
perhaps if you would like to suggest on how to create a convincing crystal base [translucent] opal,
where the Fire is inside the stone and not on the surface… i would love to learn that!
I’d expect it would be more complex to achieve then the Coober-Pedy opal in my example.
with thanks
akash
Akash,
You have given me a challenge and I will see what I can come up with. I use Brazil for my high end renders but will see what I can do with Neon and the Rhino render. It will most likely be later today as I have to go into town.
The opal you posted is very nice and would work in most jewelry designs.
Danny
Hi Akash,
Here is my result , using texture mapping. I also tested with a moonstone image. It’s ok, but not that realistic… what do you think?
Tati.
Tati Hi,
it is coming nice.
perhaps one thing with the map, [i think] is to photoshop it first to match the shape of the stone [top view] in order to minimise stretching on the visible part of the stone, it appears from your rendered image that you got a little stretching there, making it looks less realistic. maybe use a picture of a stone in the same shape as your 3D one so the optical curvature is similar to the 3D shape [just guessing here]
The white ring around the stones? is it the bezel setting…?
The example i posted was in Open GL working/designing rendered mode, [Naked Rhino] Still a beginner in this field, I knows more about cutting Opals and setting them in gold then rendering… in the example, the shape of the 3D stone is matching the physical stone, so the map [a photo of the actual stone] sits on it quite well.
Maybe it it is good to first have a “working” stone that you are happy with, and can build your jewellery around it, and then go and experiment and optimise rendering it proper.
If you like, upload your stone and the image map.
akash
Dear Tati,
I am not very experienced but read your question so I created the attached simple render images to see if they give you the effect you are looking for.
I used a jpeg image of an opal from the web and applied it to the form using the decal function in Flamingo.
Kind regards
David
Dear Tati,
I just modified the sample image to show the effect using a jpeg of a white opal mounted in silver or white gold.
I hope this is a help.
Kind regards
David
Hi Akash,
Thank you for your reply, I will consider your advice
Yes, I drew something like a bezel setting just to see how it looks in the metal. Are you a goldsmith? That’s nice!
Tati.
It’s nice, thanks David!
Dear Tati,
Please let me know if I can be of any further help.
Kind regards
David
Hi Tati
here’s a tryout with a translucent Fine Blue Crystal Opal. a bit of transparency to glass material Even though the shape of this actual stone is free-form, a round cut off seems to work out ok… so i should put in double clause some of my thought from the previous post about recommending to fit the shape of the image with the solid, would have fit better but it seems one can get away like this too.
[screen shot]
And yes i have a small goldsmith studio at: www.akashjewels.com
all the jewellery in there is solely hand work, modelling in Rhino and printing+casting is a new thing
just now working to finish engraving and setting the stones in the first printed ring.
all the very best
akash
