AE question concerning liquids

[Michael Szalapski]

All of this clearly depends on what kind of shots you’ve got.

Clearly your actors weren’t actually piercing their skin with the needle (otherwise they would be injecting air into their blood stream). So why couldn’t there be liquid in the needle?
Shoot it with liquid in it until it’s time to inject it and cut to close ups of the plunger being pushed but not having an arm in the shot. Or have the arm in the shot, but have the actual point of contact be hidden behind the arm so you don’t see the liquid dripping out.

Realistic liquid simulation is one of the most difficult things to do for any special effects artist. (That and fire. Which is why the latest Harry Potter film’s climax in the cave was so amazing.)
I don’t know of any good way in AE to fake there being liquid in the syringe for the whole scene. I think a reshoot is your best option.
You could film a syringe with liquid in it and try to match the motion (so that the liquid moves correctly) then stabilize it so you just have the needle sitting still with the liquid moving around. Then motion track that needle onto the needle in the footage. But that’s an awful lot of work and I’m not sure it’d look that good.

Now, if you shot your whole scene with liquid in the syringe up to the point of injection, you might be able to fake it. Look at how the liquid looks in the syringe. There shouldn’t be bubbles or anything in it when it’s actually being injected, so you should be able to just adjust the color of the syringe and mask it as the plunger pushes down…

Also (just for your own knowledge), 8 GB of RAM isn’t really that much for AE. My work machine has 16 GB and the new one I just bought for personal use has 24 GB.

– The Great Szalam
(The ‘Great’ stands for ‘Not So Great, in fact, Extremely Humble’)

No trees were harmed in the creation of this message, but several thousand electrons were mildly inconvenienced.

[Edward Ballinger]

Thanks, I think. Although your answer doesn’t give me much hope.

There are a few problems with the shot that I didn’t mention because I mainly just wanted some general tips on liquids and a direction to head in. Certainly I didn’t expect anyone to tell me how to do the shot step by step.

Here’s the extra little difficulty – the director wants “magic” drugs in the syringe. I guess it has to glow as well as flow with little sparkly things suspended in the solution. I figured I’d address the flow problem first and then tackle the magic part.
This may not be doable but I didn’t know. I will do some camera experiments with a syringe but re-shooting is out of the question, the job wrapped weeks ago.

Ed Ballinger
Punkmonkey Pictures
punkmonkeypictures.com

[Edward Ballinger]

Thanks guys. You’ve more or less told me what I suspected. Bear in mind that I didn’t shoot this thing, I’m late to the game. It’s a shoe-string budget that has had two different DPs that shot in short spurts over the course of the last year. I am, in fact, the fall-back editor since the main guy dropped it to go make actual money on a location job overseas.
No, I don’t really do AE as a rule. I understand that it’s an art and a science but I’ll just have to do the best I can.

So the liquid need not move much, that’s a relief. Basically I can just motion track the syringe with the “magic potion” and blend a shot of the syringe over it. Sounds like a pain but doable.

Do you have a suggestion about the close ups of the syringe? Any ideas how to make the particles and bubbles in the tube when the plunger is first pulled back?

[John Cuevas]

Couple of motion tracking tutorials that might help:

https://www.videocopilot.net/tutorials/eye_replacement/

https://www.videocopilot.net/tutorials/the_healer/

Johnny Cuevas, Editor
http://www.thinkck.com

[Michael Szalapski]

For bubbles Foam might be a good place to start.
Or Particular, if you have it. (Here’s a free bubble project)

Here’s a bunch of useful stuff on Motion Tracking.
Here’s a bunch of useful stuff on faster, better rotoscoping.

The director wants it to glow? My guess is that he didn’t think about lighting anything so that this “glowing” tube is having any sort of affect on anything around it. Here’s a tutorial on lighting up an area near a digital glow.

– The Great Szalam
(The ‘Great’ stands for ‘Not So Great, in fact, Extremely Humble’)

No trees were harmed in the creation of this message, but several thousand electrons were mildly inconvenienced.