Lens Flares

[hypersim]

My lens flare simply stops rendering when the light is off camera. How can I stop this from happening? As is, it makes the lensflare suddenly dissappear instead of slowly fading out.

[atyss]

Bonjour KnickKnack,

What you describe is a normal behaviour. A lens flare is an effect generated by a light source directly seen through camera lens. So it's normal to have it disappear as soon as the light source is not in the field of view.

What I did in a project to achieve what you want (because I think too that it's not great when the flare suddenly vanishes), is to put glow on the light source. If the glow disappears too when the light source is not visible, create an object with glow placed on the light.

Also, to enhance the effect, create a spot light. Constrain the spot to the first light, and constrain the target to the camera (optional). The idea is that the spot must face the camera. Then, put a volume light in the spot, and make it's spead angle very large, at least 60 degrees.

In the end, you'll have a surrounding "glow" that will be visible even when the light source is not. By the way, you'll have to lower the flare's intensity.

Hope this helps
Salutations - Cheers
Bernard Lebel

[hypersim]

Hi Atyss, thanks, it sort of helps.

The problem is i've got some lovely secondary flares as well as a glow that stretches across the whole of the image and when they disappear it looks plain ugly.

I don't think flares just disappear when they go off camera, they usually fade out, unless they become obstructed by some object or other; i've seen films where flares stay visible way after the light source goes off camera, and I know of other packages like 3D studio that retains the lensflare and slowly fades it out; It's just a damn shame that xsi hasn't got it's finger on the pulse when it comes to certain things.

Thanks anyway, I might follow your good advice.

Cheers,

KnickKnack

[pnoizat2]

I havent done much in the flare area but:
most naturally occuring lights arent pure point sources. thus when they leave the fov they leave gradually as the area they occupy leaves.

There is a setting in the flare options to make it behave like this, I think it puts a sphere around the light and uses it to dictate the amount of flare. i forget the name right now, I'll have a look in a bit.

hope that helps.