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View Full Version : Anybody want to share a good shiny gold surface?



sublimationman
07-21-2014, 10:55 PM
I know that metals rely heavily on the reflected backdrop and I have that OK. I use to have an excellent shiny gold (like for coins or gold bars) but I lost it somehow and every time I try now it looks too red or green and I am pulling my hair out.

So, I am looking for anyone to share a shiny gold surface and I don't care if it uses nodes or not.

Thanks!

tischbein3
07-23-2014, 12:05 AM
http://www.presetcentral.com/preset/browse/

Amurrell
07-23-2014, 05:20 AM
Here are some base RGB values that you could use to set the tone. http://simple.wikipedia.org/wiki/Gold_%28color%29

prometheus
07-23-2014, 07:00 AM
preset central dont seem to actually have any decent gold material really.
basicly for metal, use nodes and the conductor material, check william vaughans (protons) videos on setting conductor up.
and then you could probably apply the above linked info to the rgb values.
Then of course, reflections..reflections, and perhaps a slight bump noise depending on texture of the gold.

XswampyX
07-23-2014, 12:32 PM
Having a nice colour gradient driven by the incidence gives a luxurious gold finish....

http://i465.photobucket.com/albums/rr16/xXswampyXx/ThereBeGold_Node_zpsfce781f5.jpg (http://s465.photobucket.com/user/xXswampyXx/media/ThereBeGold_Node_zpsfce781f5.jpg.html)

shrox
07-23-2014, 12:57 PM
Now that's a slice of fried gold.

spherical
07-23-2014, 08:59 PM
Sweet. Took a look at the scene to learn the fine points and it occurred to me that Conductor doesn't have an IOR input. Should it? All metals/reflectives are not the same. Gold is 0.16-0.47. Is there a way to put a material together in the Node Editor to do this?

prometheus
07-24-2014, 06:48 AM
Don´t think there is any node with IOR settings for reflection, index of reflection, not in native nodes anyway.
what we have is IOR for index of refractions which isn´t the same.

I think the amount of reflection is set by conductor roughtness, how that value is corresponding to real Index of reflection, I don´t know, don´t think they are to be treated equally.
the other reflection nodes has dispersion, which I believe would be something similar to how much reflection there is, but I don´t think there is any IOR physicly based material, think that is only availbabe through octane, keyshot etc. For lightwave I reckon we have to guess the amount.

mixing reflection nodes with dispersion to plug in to conductor node, would probably have no good effect, since you can simply just use the roughness settings anyway, the question is what value you should set the roughness to, in order to match real life IOR values.

Michael

Slartibartfast
07-24-2014, 03:35 PM
Well it's a complicated subject, but after reading this: http://paristech.institutoptique.fr/site.php?id=561&fileid=7606 and some other stuff I believe there is some kind of connection between gold IOR 0.47 (wich is a absorbing conductor, not a dielectric, and it also has a complex part like 0.47 +2.95ik) and the fresnel IOR. It appears you can translate it to a fresnel IOR value of about 1.5-1.6. Interesting note (page 9 iirc) is that gold and platinum has it's lowest reflectivity, not at normal incidence, but at around 75 degrees (from normal, wich would be 15 degrees in LW-world)
Another thing- if you're not using conductor node, you should use color filtering (highlight filter) to colorize the reflections.

On the other hand - if it looks right, screw the physics ;D

sublimationman
07-24-2014, 03:42 PM
Thank you all.

For some reason I got no notification of replies to this (set it up to email me) and when I came to the board it was not bold (like no new messages). Glad I clicked on it.

Swampy, you are the master....

sublimationman
07-24-2014, 03:46 PM
123229

Maybe not as good as Swampy's but it got the job done.

Thanks again to everybody that posted.

spherical
07-24-2014, 04:16 PM
On the other hand - if it looks right, screw the physics ;D

Hehhehheh. Made my day!

spherical
07-24-2014, 04:21 PM
Don´t think there is any node with IOR settings for reflection, index of reflection, not in native nodes anyway.
what we have is IOR for index of refractions which isn´t the same.

Go here: http://refractiveindex.info/
Everything has an Index of Refraction. There is no Index of Reflection.

prometheus
07-25-2014, 06:08 AM
Go here: http://refractiveindex.info/
Everything has an Index of Refraction. There is no Index of Reflection.

yes..you are of course right, but there are some confusing physics...
https://answers.yahoo.com/question/index?qid=20071219032602AAazM3R

Maybe the transmitted light in to metal surfaces simply don´t have such big impact on how it look, since metal does´t allow for light to penetrate so much as in to skin, wax or glass etc, and maybe that´s why it simply might be enough with some
incedence angle gradient on metal?

Then again the roughness values would be interesting to know, how much a gold surface is rough/blurred or more blank in the way it reflects the light, guess it comes down to how polished the surface is?

Maybe delta or sigma2 would actually be better to use for metal, since they do have IOR .

Michael

prometheus
07-25-2014, 07:34 AM
123229

Maybe not as good as Swampy's but it got the job done.

Thanks again to everybody that posted.

Looks good, I actually like your gold tint better than Xswampy´s tinting, this is good for gold medals, Xswampy´s might be more suitable for rings, but I somehow always recognize the whitish gold tinting to be more realistic than the Green tinted one.

I think you only could use very tiny, tiny microbumps in there, maybe add some anireflections.

sublimationman
07-25-2014, 02:02 PM
Looks good, I actually like your gold tint better than Xswampy´s tinting, this is good for gold medals, Xswampy´s might be more suitable for rings, but I somehow always recognize the whitish gold tinting to be more realistic than the Green tinted one.

I think you only could use very tiny, tiny microbumps in there, maybe add some anireflections.

The industry I supply images to do not really want photo realistic, they want to ultra clean computer cg look of old. That is why I use 3D and not real photos.

prometheus
07-25-2014, 03:58 PM
The industry I supply images to do not really want photo realistic, they want to ultra clean computer cg look of old. That is why I use 3D and not real photos.

Ok ..then it should be fine as it is, no scratches at least, maybe just a slight bump anyway, buta very very low value...if any.

XswampyX
07-26-2014, 03:38 PM
Glad you liked it. :D

It's just a rough get you going / place holder texture, you can change the colours in the gradient to get any metal colour you want. It's good for chrome, copper etc...

Cheers!

Digital Hermit
08-03-2014, 12:18 PM
Having a nice colour gradient driven by the incidence gives a luxurious gold finish....

http://i465.photobucket.com/albums/rr16/xXswampyXx/ThereBeGold_Node_zpsfce781f5.jpg (http://s465.photobucket.com/user/xXswampyXx/media/ThereBeGold_Node_zpsfce781f5.jpg.html)

Swampy,

What nodes would you use recreate this in look in Octane?

Thanks!