Tiny Bubbles... on Lens

I recently tried to film river herring that were spawning. I made what I think was a mistake of inexperience in that I counted on the autofocus to work when I was unable to see through the viewfinder. This led to the tiny bubbles on the front of the lens being in perfect focus while the fish provided an interesting moving blurry background.

The next time out I'll set the focus to manual/infinity and see what I can get. The conditions do not really allow for looking through the small port of my gates housing because I'm wading in about 3' of water holding the camera underwater and chasing trying to remain still enough that the large school of herring isn't spooked.

There is a waterfall nearby that creates lots of small bubbles, these seem to attach themselves to the lens like it was a bubble magnet.

Anyone have a solution that has worked for them?

The gear I'm using is a Sony TRV 900 and a gates housing.

Well, depending on the lens, I'd focus for 1-4ft. At that depth the DoF should be close to infinity since the camera will use f8 or higher.

As well as using manual focus I would also suggest waving your hand across the port to eliminate bubble build up before each shot. Depending on your proximity to the waterfall will depend on the frequency with which you need to 'wave at the port'. I'm not sure if solutions similar to those employed by people who film surfing to avoid dribbles on the port would work but you could try them. Anyone have any suggestions? For some reason the name RainX comes to mind.

Hope all goes well,

Mark.

Lower the vis, closer the focus setting. For L&M lenses, i use .3 meters and in low vis .2 meters. put the cam in the water and focus on something with high contrast within view of the lens. hit one touch focus.

I had a similar experience recently using a borrowed camcorder on a whale trip. I had some great shots of whales breaching up close and personal, only to find well-focused water droplets on the housing port and a blur in the background. Argh!

Video Lesson 2: Don't rely on the autofocus.

(Lesson 1 is already taken: Make sure there is fresh tape at the beginning of the session.)

That's the nice thing about these boards. Hopefully I don't have to learn all the lessons from my own experience.

The first thing I do once submerged is wipe all the bubbles off my lens (that is, of course, after contorting myself to turn my air on and asking the boat crew to toss me my weights, mask, fins and computer).

I also wipe it straight after passing through a diver's exhaust bubbles.

Mark, RainOff helped a bit with this but I still needed the finger wipe.

Thanks for the info guys. I have gone back a few times and filmed the fish. I've finger-cleared the lens and it has helped. The best footage I've been able to get is to place the camera on the bottom of the stream and leave it to film for ten or fifteen minutes - the school of fish returns after I leave the camera and swims right in front of the lens. It still acumulates a few bubbles when I leave it, but by setting the manual focus the bubbles are defocused and much less of an issue than my first attempts where I used autofocus.

"The first thing I do once submerged is wipe all the bubbles off my lens (that is, of course,

after contorting myself to turn my air on and asking the boat crew to toss me my weights,

mask, fins and computer)."

Mark, that was great. Started my day off with a good healthy laugh!

I have found that a high quality mask defogger on the outside keeps bubbles from adhering to lens. This was happening to me when I took those shots looking up kelp stalks (above me where my bubbles go). If I was still shooting AF, I would get some great abstract shots. Those other methods work, but I hate to think while I dive

Charlie

This led to the tiny bubbles on the front of the lens being in perfect focus while the fish provided an interesting moving blurry background.

 

Anyone have a solution that has worked for them?

 

The gear I'm using is a Sony TRV 900 and a gates housing.

A curse on underwater video, for sure. Taped an extensive series of scenes underwater once, only to find afterwards two bubbles on the lens that were impossible to ignore on the video.

I always carry a soft rag with me and wipe my lens frequently, ALWAYS when I first submerge, and anytime I get near bubbles. I also learned to stay out of other divers' bubble streams. Those were notorious for leaving bubbles on the lens.

As for focus, I often use autofocus if the water is clear. Otherwise, I focus on my feet/flippers manually underwater at the start, and leave it there for the duration. I realize you are taping under more difficult circumstances, with the water and bubbles constantly moving. About the only recommendation I can make is to wipe the lens often. As mentioned previously, some have success with anti-fogging compound.

Good luck!

Max.