Bump map used in hologram shader?

[Kinetic99]

Hello and thanks for your time,

I've searched around and tried different ideas for producing a hologram material or shader but I'm not having the best results.

But I think what I am trying to achieve is not so much in creating a 3D object hologram effect (like in a traditional hologram made my lasers) but more about how the rainbow of colours move about on a design (for example an eagle bird) as the object is rotating in the light.
Here is the best youtube example I could find, which you have probably seen already: http://www.youtube.com/watch?v=JxYq7TJg3pU


But I want to have the spectrum colors move dynamically over the eagle design almost in a "top-down" fashion, than a left to right fasion.

So here is my idea: Is there a way to use a grey scaled image of the eagle; exactly like bump map of the Eagle and use that in some slot to dictate the movement of the colours against the light? If the rainbow of colors starts at red and finished with violet, then the high point of the grey scaled map of the eagle would be red and the lowest would be violet. Then if I rotate the object in world space the different lighting will scroll through that color spectrum- repeatly through that grey scale bump map. The results should be almost calidascope-like.

I see it my head but I'm not sure how to put in Vray.

Looking for your good thoughts, thanks again!
K

[Rens]

One way you could do this is;
- create a Gradient Ramp,
- set your spectrum colours in the ramp,
- set the Gradient Ramp to Mapped,
- put a Mix map in the Mapped slot,
- put a Falloff (perpendicular/parallel or Fresnel) map in the top and your bump map in the bottom,
- adjust the mix amount so it's somewhat mixed, you can adjust later,
- use the Gradient Ramp as the Reflection Colour.

That should be a good start.

[Kinetic99]

thanks, it is a great start but I cant seem to get the gradient of colours to move along the z-depth of the bump map when the geometry object is rotating. I got a nice transition of the gradient from left to right using "normal" setting in the gradient map as the object rotates but when I set it to "mapped" its locked in at one position.

One way you could do this is;
- create a Gradient Ramp,
- set your spectrum colours in the ramp,
- set the Gradient Ramp to Mapped,
- put a Mix map in the Mapped slot,
- put a Falloff (perpendicular/parallel or Fresnel) map in the top and your bump map in the bottom,
- adjust the mix amount so it's somewhat mixed, you can adjust later,
- use the Gradient Ramp as the Reflection Colour.

That should be a good start.

[Rens]

It shouldn't be locked if you rotate the object. Is the Falloff map set to Perpendicular/Parallel? Also make sure that your bump map goes from black to white (contrast). And make sure the Mix value isn't set to 0 or 100, try 30.

To repeat the pattern you need to either set more keys in the gradient and repeat it there, or go to the Output dropdown of the Mix Map and check Enable Color Map, then set a few point in the curve so you will get a saw tooth pattern, this will be the easier way.

To see if it works properly you can drop the Gradient Ramp into the diffuse slot, it's easier to see that way.

[Kinetic99]

its looking much better today lol. I also applied it in the self illumination slot so I can see it more. It helps ramp it up some more. But I definitely got it going and I can work with it now. Thanks so much, I'm stoked!