Re: Adding Grain to HD footage to try to look like 35mm film. AE, Smoke, Shake, Furnace?

Well,

Most of the time you want your F/X to appear organic to your shot (i.e. reality) as shot on film.

So, let's say your shot is an alien spacecraft hovering over the White House with a bright lens flare around the engine.

So we're pretending that a 'real' alien spacecraft really IS over the White House; and we just happened to catch it on film.

So we might start with a real HD second-unit plate of the White House.

Then we would comp in our CGI spaceship in the sky.

Then we would add our lens flare - tracked to the spaceship engine.

Then finally, we would add our film grain - using whatever film stock settings we like.

Adding the grain last would make it look like real artifact.

Remember - you want grain based on the FINAL DENSITY of the shot; usually with the most grain in the mid-tones.
So, although your lens flare might only be 60% bright, if you were to comp in your lens flare as a 'screen' layer mode it could push the light level up near 100% and you wouldn't have much 'grain' (just clear film base)

Good luck...

Kim

A computer once beat me at chess, but it was no match for me at kick boxing.

--Emo Philips