October 15, 2015 at 7:31AM, Edited October 15, 7:31AM

2

PRACTICAL EFFECTS - Moving cup or bowl

Hi,
I am working on a small film with some friends and in one scene I need to make a bowl shake on a table with nobody near it. Ideally you would also be able to see under the table, so I can't have anyone under it. also the table cant move.

Please can you help with any practical tips on making the bowl move?

I am sure it could be achieved through special effects but with the time and budget I have I don't think it could be achieved.

Any help welcome

Thanks in advance.

8 Comments

Stop-motion plus motion-blur in post. If you need people in the scene, but not near the bowl, shoot the people with no bowl in the scene, then composite the shaking bowl in separately. (No need for people to hold their poses through the stop-motion capture phase.)

October 15, 2015 at 12:37PM

0
Reply

Hi Michael,

Thanks for the reply, I have no experience with stop-motion, so think it might be a bit out of my skill set but I will look into it. At the moment Im thinking of only practical effects, I was thinking maybe a some sort of small motor or something inside the bowl.

What do you think?

October 16, 2015 at 4:17AM

3
Reply
Andrew Tyson
Digital Producer
73

If you cannot see into the bowl, you could cut out a bit of the bottom and create motion with hexbug nano robots that scurry and skitter around: https://www.hexbug.com/nano/hexbug-nano-single.html

The bowl would have to be fairly light and/or you might have to use several hexbugs to carry the load. But skittering around might not look like shaking, which is why I suggested something better, first.

October 16, 2015 at 5:59AM

0
Reply

I was thinking the same thing, the 1st plan is to create a false bottom inside the bowl and then maybe put some hexbugs or maybe two bigger motors inside the bowl, so that it moves around on the table. I don't want it to just vibrate across the table I am thinking one or two big jolts. I think its going to be a fun weekend of testing lol

October 16, 2015 at 7:00AM

0
Reply
Andrew Tyson
Digital Producer
73

What about moving the bowl on a green-screen background and then compositing the bowl into the final shot ?

October 15, 2015 at 1:25PM

0
Reply
Guy McLoughlin
Video Producer
29840

Hi Guy,

Thanks for getting back to me, I don't have a green-screen background, if you see my response to Michael above Im thinking of using practical effects only as my post-productions skills are no existent lol

October 16, 2015 at 4:18AM, Edited October 16, 4:18AM

0
Reply
Andrew Tyson
Digital Producer
73

Hi Andrew,
First thing first... I know how this can be done with little post work. For green screen any green colour cloth will do, only you should take care not to have that same green anywhere in you scene!
Position your camera on tripod. You cannot have any kind of camera actions (pan, tilt zoom etc.) for this special effect. First shoot the sequence without the cup on the table. Let the actors react as if the cup suddenly shook or what ever your scene is. But keep in mind, you cannot move the camera at all until you are done. Next place the green cloth piece on the table where the cup is supposed to be. Roll the camera and jolt or shake the table to give the required movement to the cup. Take care that the movement of the cup is within the green cloth area on view finder. Now take the footage on timeline and sync with the footage with the actors. Cup footage should be on the top. Crop the footage with the cup on green cloth till the cup and a little surrounding. Any NLE today has the tool to key out user selected colour from the footage. Select colour of the green cloth with the colour picker and key it out. That's it. Render and check. Tutorials on green screen is available in abundance on YouTube etc.
Practical FX- Use long wires attached to the cup from the bottom of the table and ask your friend to pull it when you need. You have to try out the wiring for the effects you are looking for. You can use cables used as clutch wires in the motorcycle as they can be moved back and forth as needed. Have fun. And yes do let us know how you did it. If you can shoot behind the scene nothing like it.

October 16, 2015 at 11:02AM

0
Reply
avatar
Dibyendu Joardar
Director of Photography
721

Depending on what you're looking for exactly, some thin fishing line and tape under the bowl might do the trick! Just have someone directly off camera give the cable a pull. It's a bit finicky, but i've made it work before to spill a glass of water. No VFX needed!

October 18, 2015 at 10:28PM

5
Reply
avatar
Craig Douglas
Writer/ Director/ Editor/ Videographer
1724

Your Comment