KeyShot Forum

Technical discussions => Materials => Topic started by: topsecretagent on August 05, 2020, 10:52:27 AM

Title: Rainbow / Holographic Glitter Material
Post by: topsecretagent on August 05, 2020, 10:52:27 AM
Does anyone have any ideas on how to create this rainbow light effect on this metal glitter?
The only thing I could come up with was to apply a color gradient to the metal material.. but the results aren't satisfactory.
It seems Keyshot doesn't have this sort of feature yet :(
Title: Re: Rainbow / Holographic Glitter Material
Post by: Eric Summers on August 05, 2020, 12:27:49 PM
Check this thread out, it might be a good starting point for you:

https://forum.keyshot.com/index.php?topic=24072.0 (https://forum.keyshot.com/index.php?topic=24072.0)
Title: Re: Rainbow / Holographic Glitter Material
Post by: topsecretagent on August 25, 2020, 02:17:02 PM
Thanks for that, I had already saw that post but I wasn't able to achieve the right effect. :/ The rainbow appears in the glitter only, so its not an easy detail to do in post either. The only way I have been able to achieve the look is by taking a photo of the actual product outside in the sun (which is when the rainbow shows the most) and compositing it on my render. This works for now, but we have more products coming in with this effect that I don't have with me physically.

Seeing my example (that I created via photo), does anybody else know how I can create this effect in keyshot? Or in post? This one has me stumped.
Title: Re: Rainbow / Holographic Glitter Material
Post by: smalldogstudio on September 14, 2020, 11:54:33 AM
Hi there,

sorry been trying to reply to this for days, been busy with lots of things - but finally here I am. I had a client request that I recreate a holographic effect on a paint can label a few months back. The approach i ended up using was to have a main label surface with a plain old label texture applied, then I had offset the label geometry in my cad package before importing (something small like 0.05mm offset? or 0.1mm) then i applied a thin film material to that with an opacity texture that knocked out the non-holographic area on the label. The client had to supply the artwork that gave me the right layers for the label, holo etc.

I experimented with the thin film thickness and reflectivity - as well as using a colour gradient to get the effect the client wanted - see the attached image, with holo on the left, without on the right. That might work for you or something along those lines.

good luck, shout if I can help further

best wishes

David aka small dog
Title: Re: Rainbow / Holographic Glitter Material
Post by: Fred B on October 20, 2020, 11:53:46 AM
Hi,

Sorry this is a little late, but I may have a start to a solution for you. I began with a metallic paint and added a gradient effect to it, then added enough pins to create a rainbow of colors, press them tight in the center, and the set the 2 end pins as the bottle color (White). If you set the pattern to angular, adjust the scale, then adjust your metal roughness and coverage you get a pretty close effect.

You may be able to tweak it to match your reference, but I attached a picture of the settings.