White Balance - another question

Yes, I know, this has been discussed many times before.. but I've not been able to find anything that addresses my particular problem, however I have heard people say they have achieved what I want succesfully...

I'm trying to improve the white balance at depth, i.e. 50 - 80 metres. I'm having limited results, doing a white balance at shallower, say 15 metres, on the descent, and then flipping in the red cc filter to give it a boost, however I'ms till not getting the colours I'd like to see. Annoyingly, another diver was on a dive with me yesterday to a wreck, his ixus pulled out some excellent results, with good colour, my video rig looked pretty drab in comparison.

We're diving in Malta, so visibility and light penetration is good, I've tried setting white balance using my buddies tanks, a white card, the surrounding sand if available and the sun, however the balance control wont set below around 15 metres. Anyone else doing deep stuff, what are your experiences, what method do you use?

We have two different cameras, a Sony HC-7 and Sony Z1, both in Gates housings.

You can see a bit of footage from one of our dives here:

http://www.vimeo.com/1659636

I used a video lamp for some of the stuff, but of course no good for thelong shots.

Bottlefish

Exactly what kind of results do you expect at depths of 50-80m? I haven't seen your video but at 80m even in the clearest of oceanic water, reds are pretty much gone. So even with a filter, you are not going to compensate for the loss of reds. The only thing you'll be doing is killing 1-2 stops of light and increasing gain.

Have you SEEN any video shot at 80m with great color in natural light ocean that isn't added in post? I confess I have not.

My deepest dive where I had some semblence of reddish magenta was around 50m in 60m viz. This was with video and direct 12pm in equatorial sunlight. Shot with a filter and 2/3" CCD Digibeta.

if you have a Z1, you might try to set the white balance to outdoor and trough the menu, after a first measure, move the white balance outdoor level manualy to achieve the color you wish within the limitations of depth and color.

Exactly what kind of results do you expect at depths of 50-80m?

As good as I can get, and always looking for ways to improve... nothing wrong with that is there?

I haven't seen your video but at 80m even in the clearest of oceanic water, reds are pretty much gone. So even with a filter, you are not going to compensate for the loss of reds. The only thing you'll be doing is killing 1-2 stops of light and increasing gain.

I'm shooting in clear water, gain set to manual, zero, and shutter speed to 1/60th. Exposure is generally fine, even at 60-70 metres with the filter in place.

Reds are gone at 15 metres, hence the need for colour correction. Of course, there's not enough light etc etc etc to white balance at full depth, but surely the deeper you do manage the more colours you are going to bring out. E.g if you set your white balance to be correct at 20 metres, whilst you wont get everything at 30, its still going to be better then doing nothing at all or leaving it on auto?

So, I'm interested to know what tricks people use when going deeper.

Itricun, thanks for the suggestion, but no help I'm afraid. The Z1 allows an offset in 7 steps of 500 kelvin from the initial outdoor setting of 5800, so at best you'll get to the indoor temp of 2300, still way off what you need for underwater balance.

The FX1 and Z1 does not have as high WB kelvin rating as other sony HDV cameras made since.

To trick it try to max - warm it to a high Kelvin..... WB on something blue before you get in then flip the CC filter in as you get deeper.

Best of both worlds would be to have a housing switch so you can flick it to a colder settings for lights and warmer one for no lights.

As good as I can get, and always looking for ways to improve... nothing wrong with that is there?

Nothing at all. I'm just wondering what your expectations are. Perhaps if you showed what sort of color the ixus came up with that you liked so much. The ixus is a p&s camera, so it MAY have a wider WB range.

I'm shooting in clear water, gain set to manual, zero, and shutter speed to 1/60th. Exposure is generally fine, even at 60-70 metres with the filter in place....

The Z1 allows an offset in 7 steps of 500 kelvin from the initial outdoor setting of 5800, so at best you'll get to the indoor temp of 2300, still way off what you need for underwater balance.

If you are able to do that, then just keep the filter on, set your preset WB temp to +7(9300°K), not -7(3200°K.) Then just correct in post. With zero gain, you can bring up the reds in post without too much color noise. When you shoot with lights, do a manual WB for the lights. This all depends on what housing you have and tthe controls you have access to. If you can switch between WB settings, keep WB A for deep water and use the preset for lights.

Alternatively, you can try doing a MWB every 5m or so with a gray card and filter upfront.

If you are able to do that, then just keep the filter on, set your preset WB temp to +7(9300°K), not -7(3200°K.) Then just correct in post. With zero gain, you can bring up the reds in post without too much color noise. When you shoot with lights, do a manual WB for the lights. This all depends on what housing you have and tthe controls you have access to. If you can switch between WB settings, keep WB A for deep water and use the preset for lights.

Alternatively, you can try doing a MWB every 5m or so with a gray card and filter upfront.

I'll try and get a copy of the photos from the Ixus - not sure if he was using manual white balance, or the underwater setting, either way it gave remarkably good results (in fairness, that was at about 50 metres)

I'll have a play with the +/- on outdoor, see how that works - the gates housing allows access to pretty much all the controls, so I can switch between easily. I've been avoiding post edit correction for now, but will also have a go at that, see if it helps any.

Thanks for the advice

Stu