vray and lens effects

[Shaun Hamm]

I'm trying to emulate a starburst glare effect that you see in MR lights. I've found a couple video tutorials saying to add the environment/lens effect/star and glow to omni lights but I am still unable to see the effect when rendering using a vray physical camera.

 

Does this not work with vray physical cameras and lights? Or is there another method I should be using?

 

Oh, and it's gonna be for a animation so i can't add it in post.

 

Thanks for any suggestions.

 

-Shaun

[Crazy Homeless Guy]

I'm trying to emulate a starburst glare effect that you see in MR lights. I've found a couple video tutorials saying to add the environment/lens effect/star and glow to omni lights but I am still unable to see the effect when rendering using a vray physical camera.

 

Does this not work with vray physical cameras and lights? Or is there another method I should be using?

 

Oh, and it's gonna be for a animation so i can't add it in post.

 

Thanks for any suggestions.

 

-Shaun

 

Are you sure you can't do it in post? ...I am working on an animation this morning where I am adding glare to lights in post. Similar to the way I would in Photoshop by creating a glare on a black layer, and setting it to a screen transfer mode. Then I am manually tracking the light, and scaling/fading as needed. It is not perfect, and maybe not the best way, but it will work.

 

Currently I only have 2 of the lights started, and they both still need refining.

 

Also, I think Vlado said this is a feature that has been implemented on future versions. I don’t know if it is a 2.0 feature, or if it will be a service pack.

 

http://www.phase22.com/misc/cgarchitect/Glare.wmv

[Shaun Hamm]

Thanks, Travis. I was trying to avoid adding it in post. I jumped over to the chaos forums and saw the thread about adding it in the future. This would be a very helpful feature.

[Crazy Homeless Guy]

I have liked the results I have received in Mental Ray with it, but it is annoying at times because it is 'burnt' into the scene. Ideally it would be best as a render element, that can be directly composited in post.

 

Mental Ray does have the feature to render it out as a pass by itself, but the feature requires replacing the existing image, so you still have to render out the frame in a separate pass. A render element would render it at the same time, and then allow you to apply it as a screen layer in post, and adjust the effect it has on the image.

 

Anyway, I am looking forward to that as an addition to Vray also.

[Justin Hunt]

you can apply the effect to already rendered frames by using them as a backround image. Then you can either output the Glare burn into the frames or just the glare to be comped in Post

 

check this post http://forums.cgarchitect.com/41081-glare-applied-background-image.html

 

jhv

[Crazy Homeless Guy]

Hmmm... so the images can be rendered in Vray, and then applied as a background image with the engine set to Mental Ray, and using the glare shader. That is what I call using your resources wisely.

[Justin Hunt]

and its quick

[3DMK]

There are lots of ways you can do it in post.

 

My preference is to use a plugin called Optical Flares in After effects.

 

Simply save your V-ray SELF ILLUMINATION render pass & get the plugin to use the luminence value of the render pass. [This method works best with 32bit image formats]

 

Or an even more precise way is to use Max to AE plugin which can export the actual lights to AE in 3D space. The pugin will then take into account the actual distance from camera & light intensity to create much better flares....you may need to create a mask in vray to tell the plugin when the lights goes behind an object

 

**You may run into problems using Scanline or Mental ray to generate flares if you are using Vray proxies as they won't recognise them.

 

Hope this helps

[Crazy Homeless Guy]

**You may run into problems using Scanline or Mental ray to generate flares if you are using Vray proxies as they won't recognise them.

 

Hope this helps

 

I will look into your other methods, particularly the second method. I have been looking to incorporate the 2 into a tighter work environment.

 

But what Justin was talking about was using a blank scene with the Mental Ray render engine and a already rendered EXR set to be rendered as the background image. There does not need to be any geometry in the scene. You then play with the Mental Glare shader to produce the effect you want off of that image.

 

This is essentially the same as the first method you described but the post pass is done in Max instead of Aftereffects. Which is better would come down to which plugin is more robust.

[Shaun Hamm]

ok, here's a update...it also came to my attention that the client wants the lights to "twinkle" so the after effects method seems to be the best way to go.

 

here is a test i made adding them to a still image and then panning/zooming the image and tracking them with it.

 

http://dl.dropbox.com/u/8659879/twinkle%20test.mp4