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Does anyone have a few secs of video that shows before and after white balance adjustments while shooting in green water? I am learning my SR12 in the L&M Stingray Plus housing. Many thanks in advance
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details please!
What camcorder and which housing?
Are you doing a Manual white balance with a white card? Steps, please!
What depth?
Any issues noted?
Did you do any post dive tweaking?
OK, this video was made using my older Sony VX-2000 that I now use as my surface camera. The camera is mounted in a Gates Housing and uses a super-wide Fathom Imaging SWP-35 port (110 degree view angle). This was one of the best SD professional older generation set-ups previously available, generally used for TV production. I bought everything used from e-Bay, but recently bought a new Sony PD-170 camera to replace the VX-2000 in the same housing and had the port remanufactured. This was my first underwater video with the older camera in the older port, so I didn't really know that much.
There is much discussion these days about adjusting white balance in post production and I'm still trying to figure out FCP Color to do a better job of that. I'd say that if you started as green as some of these clips, post production will never restore true color.
If I'm shooting without lights (like my previous video), I like using MWB underwater. In this video you saw numerous white objects underwater, all of which I used to white balance from. I'd suggest getting a few feet away, zooming in tight so all you see is white, hit the white balance control and the camera will adjust. I'm now using an attached slate to do the same thing, very close up, but keep in mind I have a VERY wide angle port. Just for reference in the video, I used the buckets, my buddy's arm slate and the PADI sticker on the van. I've also used the sun very effectively in open water, when it's at a higher angle. Find the brightest spot above you, zoom in tight, then MWB. In all of these, don't worry about focus, it's probably better to be unfocused.
If you are using manual f-stop settings and shutter controls, it's important to get these set before you white balance. Changing these settings changes the amount of light available to the camera. Using auto exposure controls will constantly change the lighting of your subjects underwater when shooting in natural light, so I'd avoid it. I use an external monitor and when the monitor picture is decently bright, I'm usually close to the correct settings. In this video, the f-stop (aperture) would have been around 4.8, maybe 5.6 near the surface, with the shutter speed set at 1/60. I've noticed on deeper dives, it's better to white balance continually on the way down. As it gets darker and bluer the camera will struggle to keep up, until it can't adjust. Then when you MWB, it will just blink at you.
Please keep in mind, the Sony VX-2000 is an extremely low-lux rated camera. It will produce decent quality video in a mostly dark room, making it ideal for underwater use. I also suggest using a blue water filter for adding the reds back in from 10 to about 40 ft of clear water, switching to a green water filter from 40 to about 140 FT in the same clear water. This helps the camera white balance without a radical red shift and in darker water may extend the depth you can shoot in natural light. The short video of the USS Tarpon below (no post work on video) was shot in natural light using a green water filter and MWB at 140 FT. In darker water, no filter. Your results may differ.
When I switch on HID lights underwater, MWB on my camera does not work well. I'm taking it to the lake soon to figure this out, but for some reason it has a red shift I can't beat (i.e., any artificial light looks very red after MWB, and NO, I don't have a filter in, LOL). BUT, when I switch to auto-white balance in the "outdoor setting," the picture comes in great. I have noticed that I need to notch the f-stop open even more, so a setting of 4 or 3.4 would not be unusual. This limits the filming area to about 5 to 7 ft in front of me using the SWP port and artificial light, but it still turns out good. Needless to say, I shoot wide angle, so artificial light has limited effectiveness for me anyway. My purpose for adding HID lighting is to better illuminate sharks as they come toward me in frame, but I need much more practice with this technique in a lake when I'm not dragging around so much equipment. The lake you see in my previous video is my practice lake. It's deepest point is about 60 FT.
I linked the Tarpon video below. I've also linked a kind of fun tutorial video on the VX-2000 camera from YouTube that shows the effects of different camera settings. It can apply to any camera you may be using and it is fun to watch.
OK, "poor man's" MWB in an automatic camera. With the camera running, set everything up I said in the post above. Zoom in, unfocused, about 5 FT or so from subject, or straight into the overhead sun (best method for this technique in a BRIGHT sun). Freeze the camera. Switch it off, wait 5 seconds, switch it back on. Hold for about 15 seconds even after picture is viewable. ZOOM OUT quickly while turning away from the white object. This will work about 80% of the time and I've used it when I've encountered control arm problems.
There is a "BUT." If you encounter another white object with an auto WB camera underwater, even 30% of frame, the camera will probably rebalance incorrectly. This will screw stuff up. Repeat the procedure again.
My web site links to several videos from the Pacific North West. The GB Church wreck in particular was auto white balance for the 98-2008 retrospective, while the 2009 footage was manual white balance. I can remove the green completely, but I balance with a bit of halogen light so I get a slightly green background. The camera is a Panasonic pg 150.
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