Correcting white balance in underwater photos

[ADiver]

Over the years I have taken quite a number of underwater photos and videos. I have recently bought a Canon G16 and its housing and want at last to start taking pictures which have correct white balance. I will try the camera's own AWB facility and shoot RAW normally. But frequently an opportunity comes up that does not permit messing about sorting AWB, so it gets done in RAW and then needs postprocessing. My editing software is Photoshop Elements 11. I have been trying to perform WB correction on previous UW photos, which have been on Canon G9 or S100 and have met with no success. Is PSE the right tool for this job? Most of the tutorials I have read seem to use Photoshop proper.
I am alarmingly ignorant and have been trying to get up to speed on histograms etc. But if PSE is not right, I would like to stop wasting my time.
All advice welcome!
Alex

[Manfred M]

Hi - welcome to CiC, Alex.

While I am a very experienced scuba diver, underwater photography is not something I've gotten into (lack of vis up these ways is probably the main reason). PSE should be more than adequate for colour correction, as it uses the same basic engine as Photoshop itself. If you could post some of the images you are having issues with, we might be able to help.

The issue with underwater photography is that you are shooting through a massive "blue" filter, whose density increases with depth, so your reds and yellows will start cutting out as you go deeper, unless you shoot with a flash to add those wavelengths back.

[benm]

The issue with underwater photography is that you are shooting through a massive "blue" filter, whose density increases with depth, so your reds and yellows will start cutting out as you go deeper, unless you shoot with a flash to add those wavelengths back.

Alex, because of this I do not think you can adjust WB - there is no/almost no red to adjust. My underwater photography improved overnight when I got a big Ikelite flash unit. Above water the flash housing was a bright deep red; underwater a very pale pink/gray.

[Glenn NK]

I'm afraid that Manfred and Ben are right; there is no WB that will get the colours back simply because the colours are not there.

The first colour to go is red and so on across the spectrum.

Underwater flash is essential unless you are only diving to snorkeling depths.

Glenn

[ADiver]

Thanks for your responses. Are you implying that using the inbuilt AWB feature (using either a white card or light sand) will actually not work - or even a red filter?
Up to 5 metres or so there is no problem and I do use flash (though not an Ikelite) for many of my pictures.
Back to the drawing board!
ALex

[Manfred M]

Thanks for your responses. Are you implying that using the inbuilt AWB feature (using either a white card or light sand) will actually not work - or even a red filter?
Up to 5 metres or so there is no problem and I do use flash (though not an Ikelite) for many of my pictures.
Back to the drawing board!
ALex

Just think about the colours that you see (and don't see) as you go deeper. Near the surface; i.e. your 5m referernce, the reds and yellows will penetrate to some extent, but once you get down into the 20 - 30m range, things rather monochrome (unless you have a dive light along).

AWB cannot add / correct colours that are not there. Look at a theatre shot with gelled lights - the other colours are filtered out, and the camera cannot record what is not there. Adding a red filter will merely remove the blue end of the spectrum and will increase the need for exposure significantly without adding the non-existant red back into the image.

If you want full-spectrum images, you are going to have to take along a light source (i.e. flash) that puts that part of the spectrum back. There is no other way of getting those colours into deeper water.

[GrahamS]

Remember also that the water is effectively a blue/green filter whose density varies according to not only depth, but horizontal distance as well. The further away from the camera, the greater the filter effect. This can cause severe colour problems even when the water is crystal clear.

[RustBeltRaw]

A red filter can help. I use a snap-on, $30 version for my GoPro 3. It doesn't produce "accurate" color (only extra light can do that), but it does make things look more natural at the expense of a noisier shot.

Fairly craptastic sample video below. Max depth 128ft (39m).

[rpcrowe]

I don't dive but when I was in the Navy Combat Camera Group, we had a dive locker in our unit and our diver photographers always used supplementary lights - either flash for still images or continuous light for motion picture (video would be the same).

If there are no reds in the subject you are shooting, there is no way that you can increase the red.