Is this compositing idea going to work?

[TOBIB]

So I have this idea in mind but I'm not sure if it will work since my compositing experience is a bit limited:

The idea is to shot each scene twice: Once with actors wearing makeup under blacklight and once in the night on location without the actors. Now I was thinking of simply keying out the black on the blacklight shots and place those over the real location shots. Will this work in theory?

Of course provided I'll keep the angles and camera positions equal in both shots.

I'll only use static tripod shots for this.

 

[directorik]

Seems sound in theory.

What would be really cool is if you were to do it - just
a 20/30 second clip - and post it for all of us to see.
I'd love to see you give it a try. Then you could tell us
what worked and what didn't and perhaps a better way.

But then, I've always been a hands on kind of movie
maker. I like to give it a shot and not just play with
theory.

 

[TOBIB]

Ya, I'll try to do that tomorrow.
I think the hardest part will be getting the perspectives and depth of field right in every shot. Along with removing the outlines of the keeying so it looks natural.

 

[wheatgrinder]

Sound cool.. tape measure is your friend

 

[wheatgrinder]

Im thinking a sloppy keying job might look pretty cool too.. like your half in and half out of the same movie.. might have to try a variation on this idea..

 

[TOBIB]

Agreed, but I wan't to keep it as natural as possible. I want the audience to think its green screen with expensive cgi when it's actually pretty cheap.

Thanks for the measure tape reminder.

 

[wheatgrinder]

I think the key is keeping the same focal plane, zoom and camera position in both the A and B shots. If you set a nice shallow DOF where the actors come in and out of focus by moving to and from in relation to the camera.. Be sure to keep that same DOF when you bring the background lights up, likely the background will be OUT OF FOCUS but thats the idea.. Go for several\many very short shots, so you get a sense of moving around without having to pan, push, pull or zoom the actual individual shots. The tape measure is so you can match the focus distance between the two A\B shots. (what IS the right term for that AB?)

Bringing up the lights on the background will very likely change your exposure, thereby tweaking your DOF, so you cant just "set and forget" Seems you'll likely have to make different adjustments to the focus and exposure settings to get the same DOF in both the AB shots.

 

[TOBIB]

Here is some test shot I made with basic post-processing done in after effects: http://www.youtube.com/watch?v=YjlhhNsrNeY

I think it works pretty well all tough the image is pretty flat. I might want to keep an eye out for that when planing the shots.

What do you think?

 

[Yodaman]

How long is the video? YouTube keeps telling me it's still processing.

 

[TOBIB]

Yes I was wondering as well. It works now.

 

[wheatgrinder]

That came out COOL as all heck! The focus is a bit off, or maybe its the masking is too feathered.. Id like to see the black light stuff "sharper" but maybe this is what your going for..

Great work and thank you SO MUCH for posting your results..

 

[wheatgrinder]

oh, and the BLACK makeup around the mouth worked VERY well.

 

[directorik]

This is why I'm a "just do it" kind of filmmaker. I had
no idea from your first post that this was the effect
you were going for. From your question I had something
completely different in my head.

That test looks really cool. I like the effect a lot.

 

[rogypro]

this is sweet

 

[TOBIB]

Thanks, I'm glad it is received well by the audience.

The focus is a bit off, or maybe its the masking is too feathered.. Id like to see the black light stuff "sharper" but maybe this is what your going for..

Yes, I used a lot of feathering as a cheap way to make the whole mask appear "ghostly". I might change that in the final result.

 

[Yodaman]

Wow! That looked COOL!

 

[backlash]

If you want to do ghosts then it's really nice.

I read that you wanted people to think that you used a green screen and high costs techniques...

My green screen costs 10 euros (15 US $), I shoot with a not expensive HD camera, and we even used imovie (free) to swap the background. And it works.