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The Publisher
09-03-2007, 04:20 AM
There seems to be a lot of confusion on how to white balance an underwater videocam since there are so many variables, so let's see if we can ad some techniques here favored by some of us.

This will not be the cure-all, try some of the different techniques and see what gives you the best results.

Since water filters out first the red spectrum, many videographers and housing manufacturers try to add the red back by adding a reddish or orange colored flip down filter to put the warmer tones back into the footage.

Other's use a "warming" white balance slate, such as Amphibico's excellent offering.

http://amphibico.com:80/amphibico/images/image/1.1000182.ACWB0711blSM.jpg

You'll notice that Amphibico's slate is not white, but a blue-green. The purpose of this is to do the same thing a reddish orange filter would do-warm up the image. That is also why you either need one or the other, not both! I've white balanced with a blue-green slate, then flipped down the red color correction filter, what a reddish mess!

Now if you don't have such a slate, you can attempt to get a piece of Plexiglas near the same color, or some adhesive film that is the same color as the Amphibico white balance slate. If course you'll spend more time then it is worth driving all over kingdom come, but I know some of you are terminal tinkerers. ;)

Some videographers forgo using a white balance slate all together and white balance against light colored sand underwater, and I've even heard guys saying they point their videocams towards the surface. I tried it and the results were better than not white balancing at all.

The issue with sand is it can be inconsistent, but you can usually pick up on this on your videocam monitor. But if you're like me, if after 10 dives you spot that elusive Periclimenes imperator AND it is staying on top of the sea slug calling you out to video him, white balancing is the LAST thing I will remember in my kid-in-the-candy store rush to video capture those amazing animals.

The other issue is, for those who like to shoot closeups and thus use supplemental lighting, white balance WITH the lights on.

Always white balance with the way you're going to be shooting.

So to recap just one videographers technique:

Lights on, white balance against slate, no color correction filter

Lights off, wide angle, white balance against slate and then flip down color correction filter

Lights off, wide angle, white balance against Amphibico's blueish-green slate, maybe do not use color correction filter, test

Lights off, macro, white balance against Amphibico's blueish-green slate, do not use color correction filter.

I didn't list a lights on wide angle, because the lights will not work much past 1 meter/3 feet.

And remember, when you can, white balance at the beginning of EVERY shot if possible.

Lastly, if things don't go perfect, but close, you can always color correct in post, you just do need at least something halfway there as an overly blue/grayed out clip is often beyond hope. Getting good color balanced footage FIRST is better than trying to fix it in post.

If others have particular white balancing tips they would like to share, go ahead an ad to this thread.

Papa Bear
01-30-2008, 05:05 AM
Don't forget to adjust with depth changes! That is the most important! If you are on the reef at 60ft set it once for all 60ft shoots will probably work as long as you don't change the back ground. But if you go to 70ft or 50ft that makes a bigger difference. My two cents!

bottlefish
05-22-2008, 04:37 PM
Other's use a white balance slate, such as Amphibico's excellent offering.

http://amphibico.com:80/amphibico/images/image/1.1000182.ACWB0711blSM.jpg

You'll notice that Amphibico's slate is not white, but a blueish green. The purpose of this is to do the same thing an reddish orange filter would do-warm up the image. That is also why you either need one or the other, not both! I've color corrected with a blue-green slate, then flipped down the red color correction filter, what a reddish mess!

I'm a bit confused by this... In my understanding, if you use a pure white slate, then the slate will appear bluer as you descend, as the lower frequency lights get cut out. Focusing the white balancing control on the slate, the video can then do the necessary to adjust that back to white.

If you use a blue coloured slate as a starting point, surely the camera is going to overcompensate? Or is the amphibico version designed for use at the surface to precalibrate before your dive (in which case, as Papa says, it's going to be optimised at a certain depth, over or under at others?)

Another question, are there any tricks in setting the white balance when light is a bit lower? I was on a dive last week, playing with a Sony HC-7, and could not get the white balance to set. I was at 30'ish metres, visibility and light were a bit low, although not terrible.

Final question, has anyone tried using a colour card at the start of a dive, and then adjusting the colours post edit, using the colour card as the template/control?

The Publisher
05-22-2008, 07:56 PM
I think Ampibico's idea was to use a blue-green slate to wb at every major depth change to deliberately overcompensate so as to add more red into the mix and possibly alleviate the need for a red filter, plus your depth does not matter as much, as the slate is held right in front of the dome port.

David White
05-26-2008, 05:28 AM
Generally during the day I film without lights and with the red filter in place. Each shot is white balanced electronically using Amphibico's white balance chart. This does not always produce perfect results since the distance from the lens to the white balance chart and from the lens to the subject may be different or the sun can go behind a cloud affecting the amount of available light or the subject moves thereby changing your angle to the light. Some colour balancing in post can rectify minor adjustment requirements.

The Publisher
05-26-2008, 06:04 AM
I have not had great luck with wb'ing on this slate to the point of not needing a red filter for wide angle on the rare occasions I am not shooting macro.

bottlefish
05-27-2008, 09:25 AM
The subjects I'm talking about are deep wrecks, 60 - 120 metres, so I need a way to try and increase the colours a little bit. A red filter isn't an option, it will cut out too much light. Using a video light will help on the close ups, however it wont have the cut through for the long shots.... but ideally I want to be adjusting the video settings as little as possible, given the limited time I'll have at depth.

I noticed that the amphibico offering has a colour slate on the reverse, so I'll have an experiment and see how I get on. Any other suggestions for improving the colour at depth, gratefull received.

The Publisher
05-27-2008, 02:42 PM
Yes white balance against a warming slate, while rolling turn it over the the color chart, then in post, trying adjusting the spectrum to match the color chart you dove with by having it with you at the computer and compare and get as close as you can.

danvolker
03-13-2011, 08:08 PM
Yes white balance against a warming slate, while rolling turn it over the the color chart, then in post, trying adjusting the spectrum to match the color chart you dove with by having it with you at the computer and compare and get as close as you can.

For quickly changing deep ocean environments, how about shooting a slate on your dive buddy --just get him or her to swim out in front of your desired shot asap for each new one.....so far I have been using AWB and auto for iso and exposure for my new canon 5 d mark II in Aquatica housing --no lights.
I am done with the auto lighting, and am about to begin using full manual exposure and iso. Sample shot with the auto nonsense ..
http://www.youtube.com/watch?v=GH7_q5ACzXA

I will have to spend the next few dives figuring out the right iso settings, as well as setting the exposure, and seeing how well the light level works in the target area as I shoot down a reef line....most of what I am doing is showcasing Palm Beach county reefs for structure and marine life.

I do have access to some big Halcyon canister lights with diffused heads....I could try this, but my thinking was that by shooting with ambient light, I can show far more distance and far more reef structure than would be possible with even big HID lights.
What do you guys think?

Dan
www.sfdj.com

lars2923
03-14-2011, 12:21 AM
I bought the Canon 5D Mark II and was not planning on using for video but this video was made with the Canon 5D MArk II ? If yes, OK, I'm using the video. Too bad it's limited to so many minues or 4GB (I believe that is 4GB)

danvolker
03-14-2011, 01:50 AM
I bought the Canon 5D Mark II and was not planning on using for video but this video was made with the Canon 5D MArk II ? If yes, OK, I'm using the video. Too bad it's limited to so many minues or 4GB (I believe that is 4GB)

Yes, canon 5 d mark II in aquatica housing without lights....but I need to begin shooting with iso locked down, and with manual exposure...this will all be new to me ...

lars2923
03-14-2011, 02:18 AM
It's the same housing I am looking into. It appears you have a wide or ultra wide dome and/or you ar eusing a wide angle lens? Which lens did you use for that dive, do you remember? And your dome. Heck, spill it out for us, give us (OK - give me) a list of what you got?

Are you new to UW Photo/Video?

L

danvolker
03-14-2011, 03:04 AM
I use the canon 16 to 35 mm lens.
The aquatica has a dome they sell for this rectilinear lens.


I am new to underwater video... I shot a little topside a few years back with a mini dv camera, but this u/w stuff for only about a month and a half.



Dan

lars2923
03-14-2011, 03:16 AM
I use the canon 16 to 35 mm lens.
The aquatica has a dome they sell for this rectilinear lens.


I am new to underwater video... I shot a little topside a few years back with a mini dv camera, but this u/w stuff for only about a month and a half.



Dan
I have the exact same lens and a lens that will fit into the super dome. Awesome combination, especially if this is your first rig. Great choices so far.
When looking at lights, look at the light/strobe combination from Ikelite.

At first, you are all about learning this and doing that and oh I wish I knew that when you watch your film. Beyond some of the tips Publisher provided, try and hold the unit steady. One way is not to hold the unit tight, but almost with your fingers (depending on conditions) and as a general rule, Dainty like. When turning, try moving the back of the camera on an arc vs turning the camera front to follow an object. When you think you shot enough, shoot some more. 10 seconds is a good rule to give enough time and room for editing, yada yada ... Just keep doing what your doing and you'll get it.

Great job on the rig!

danvolker
03-14-2011, 02:47 PM
I have the exact same lens and a lens that will fit into the super dome. Awesome combination, especially if this is your first rig. Great choices so far.
When looking at lights, look at the light/strobe combination from Ikelite.

At first, you are all about learning this and doing that and oh I wish I knew that when you watch your film. Beyond some of the tips Publisher provided, try and hold the unit steady. One way is not to hold the unit tight, but almost with your fingers (depending on conditions) and as a general rule, Dainty like. When turning, try moving the back of the camera on an arc vs turning the camera front to follow an object. When you think you shot enough, shoot some more. 10 seconds is a good rule to give enough time and room for editing, yada yada ... Just keep doing what your doing and you'll get it.

Great job on the rig!

Thanks. I will try your tips.

Dan

Okeanos
03-14-2011, 07:31 PM
I always set my white balance by pointing the camera at the surface, it is the light source after all. If I want it a bit warmer I change the angle slightly until I am happy with it.

I do the same for stills or video, and, no post processing.

lars2923
05-31-2011, 08:08 PM
Question on focusing.
Using the housing and dome you mentioned, how does one focus on the subject?
I have not purchased the housing/dome yet and was just wondering.

Thanx,
L