Advice for KEYING out WATER

[Yves Bourgeois]

It’s very important for me to able to manipulate the water separately from the background. As I mentioned, the water will be shot at a very fast framerate, or at least slowed down drastically in post, and I want to place it in an environment that is realtime, as well as be able to place it in more than one environment. This is why I want to key it out, being able to isolate and control it separately from the background is imperative for this project.

And just to be clear, I’ll be throwing varying amounts of of water in the air, from a few drops to large amounts on different shots.

[Mark Suszko]

It’s been done already…

https://www.digitaljuice.com/products/products.asp?pid=1592

And they have more, including paint throws.

[Mark Suszko]

You shoot against black and you don’t need to key, just change the blending or transfer mode, and it is in your new scene ready to use.

[Yves Bourgeois]

Hey thanks guys,

@Mark, that’s good to hear re:
You shoot against black and you don’t need to key, just change the blending or transfer mode, and it is in your new scene ready to use.

I was expecting to use luma key, but that sounds easier. Have you every tried anything like this? Do think it would come out clean?

@Dave, I did not include that level of detail because I did not think it was relevant. There is no other subject, just a background or environment in the shot, and yes the water is indeed clear.

I did not include the actual framerate either because it not yet determined! If you see my original post, I mention that I would want to do the slow-mo in camera, and if not use Twixtor, but it’s still budget depending at this stage. I am also aware of Twixtor’s limitations, but it can give very interesting results.

The reason for posting in the first place is to get some technical advice, possibly even from people with experience with this subject matter, for how deal with this in post and how to light accordingly. I will of course do some tests if I can, but again the amount of testing is budget dependent and it might not even be a possibility.

As I mentioned, I am still in pre-production but trying to anticipate problems down the road by seeking advice. I work in post-prod and want to properly plan this shoot so that it flows in every stage of production, instead of trying to just “fix it in post”.

[Yves Bourgeois]

I’ll definitely play around with the blend modes when I have some footage, it’s just good to hear that it sounds feasible. At this stage, I am doing preliminary research, and am trying to avoid trowing myself into a project that can’t even work technically. If I can come out with a clean picture, and not pull out all hair in process, I’ll be happy.

And as for the framerate, that will come in time.

[Erik Eliason]

Wow Yves, that was a lot of explaining to do for your simple question 😉

I am too in pre-production of the same task, shooting water in slo-mo with green screen. I normally work in post so using Key Light in AE is what I have good experience of.
Will use the Sony fs700 at 240fps and eventually some Twixtor on top of that.

I will color the water red so I imagine it to be easier to pull the key than with just plain water but I’m still curios of your experience and final solutions. Did you get all details of the water highlights and shadows? Did you go with black BG or green screen in the end?
Do you have a link to what you shot?
Any thoughts on illumination design?

Best //Erik