Home of Professional Cinematography since 1996
Published : 5th July 2004
I've got a spot coming up (hair commercial) where the director plans to use bubbles as a transitional device between segments. I've never shot bubbles before. I've got some macro lenses and a 25-250 Ang. zoom. How fast should we run the camera (435)? Lighting tips and background ideas would be much appreciated. CG not an option.
Thanks in advance...
Nicholas Hoffman wrote:
>Hi all, I've got a spot coming up (hair commercial) where the director >plans to use bubbles as a transitional device
This sure sounds like a situation where you should explore the possibility doing the transition in post, using some kind of 3D software. I believe it would be a particle effect, and suspect you may be able to get some pretty realistic stuff going. If it were me I would discuss this with the Producer and Director.
Also, your specifics are vague. what kind of bubbles? Lawrence Welk-like bubble machine? Bubble bath suds? Great big bubbles from one of those gigantic bubble wands?
Just some thoughts.
Nashville, TN USA
I did bubbles not long ago, for a cosmetics company.
Clairmont macro lens (the Isco, as I recall, I'll have to check, we had also tested a few others). The only lens we found capable of 10:1 magnification. The art director wanted a single Champaign bubble to fill the entire screen.
Also, high speed, up to 150 FPS. For this we needed an f/stop of about f/128 or above at the subject (incident) in order to have enough depth-of-field to keep the entire bubble in focus. After various filter factors, high speed, etc. the actual stop on the lens was about f/32 or thereabouts as I recall. Just barely enough to hold the depth-of-field. I wrapped the Minolta mini-probe in plastic wrap in order to get readings at the subject.
A small chamber made from two 4x5 optical clear filters, front and back. Other arrangements were tried such as nitrogen in mineral oil, etc.; none of which were acceptable. We were never able to get pharmacy-grade, purified mineral oil to be acceptably clean and optically transparent.
Lighting: a 12K HMI PAR about 30 inches away from the subject. Extensive heat dissipation and protection precautions, obviously.
Clairmont strobes (similar to Unilux) had been tried on a test day, but proved inadequate for the stop we needed. As I recall we rigged some six or seven strobe heads, together with a 6K PAR and a 4K PAR. Also, the art director didn't like the pattern of highlights on the bubble in this arrangement. We "blended" the strobes with diffusion, of course, but it still didn't produce the clean, singular highlights he wanted.
Even with that firepower, ended up having the film pushed one stop; it still looked great. Kodak Vision stock took the push and was hardly noticeable. Two days of shooting; only got it on the last take.
The final secret: use cheap Champaign â€” the bubbles are larger.