Available light underwater photo advice?

As I posted in another thread, my trip to St. John (USVI) this fall will be my first attempt at underwater photography. I have purchased the cheapest rig that I could come up with--Olympus C-5000 with Olympus PT-019 housing--that should still give me the opportunity to come away with some decent shots. There is a chance that we will be scuba diving, but the majority of the trip will be spent snorkeling.

I found a very interesting thread on these forums about available light underwater photography:

wetpixel.com/forums/index.php?showtopic=2820&hl=book&st=20

This is the type of shooting that I plan on doing, as I can't really afford a strobe at this time. We will be in clear shallow waters anyway, and so I'm not sure a strobe would be necessary anyway.

My question then is....Is a color correction filter necessary if I use custom white balance in shallow waters? If it is necessary, what would be a reasonably priced, good quality filter to use?

As always, thanks for the help

I have found that the underwater mode on my Canon G9 works really well in depths under 25 feet with good sun. I think the trick to available light underwater - with filters or without - is to get the sun in the "right" place.

JMHO

Resident available light guru is forum moderator/admin Dr. Alex Mustard ... his "magic filters" are affordable and very useful for ambient light photography underwater ... Link to Magic Filter site ...

Here's two - first shot with the "magic filter" and the second with no filter, but using the underwater color balance from Canon:

Like Jeremy,

I have used the underwater mode on various Canon cameras in shallow water with nice results.

I do not know if your camera has that exposure setting however.

I have not tried the magic filter yet but plan to get to it eventually.

Here is a FREE option.

Become a 'beta' tester for version 2.0 of lightroom

http://labs.adobe.com/technologies/lightroom/

It has color balance options that can help you with photos you are not satisfied with, or perhaps improve a few you like. I find it easy to use but I bought the earlier version about a week before the free beta deal came out.

You basically pick something in your photo that is close to white (white sand works which you may have at USVI) and tell the software to make that 'white'. all other colors change accordingly. Its simple enough even I can use it.

Dave

Jeremy,

Thanks for sharing your experience and the sample pics. I will take a look at the filter you recommended.

Dave,

I usually shoot RAW, and make adjustments in Adobe Camera Raw, then final edits in CS2. However, my underwater camera--the C-5000--does not have RAW as an option. So I will need to get the white balance correct when shooting. There is not an underwater mode, but I would think using a white card and manual white balance would be easy enough.

It sounds like a filter will probably not be necessary for snorkeling, but would be necessary/useful for scuba diving at greater depths.

Thanks.

Just set your camera to "cloudy" as that has about the right color temperature. I used to shoot with a Canon SD630, which does not have a raw mode and the underwater mode disabled the exposure bias and other controls I wanted to use. Using the "cloudy" mode gave me very good results. I still use it now with my dSLR to get the JPEG out right (I use raw+jpeg).

Dunadin,

Interesting thought...and that would certainly be a reasonable solution if I was in the water, and didn't have a white card. However, with a white card, manual white balance should give me a more accurate reading.

I would still like to learn more about the necessity of using a warming optical filter at certain depths. It would be interesting to see a JPEG comparison using a red optical filter and manual white balance vs. manual white balance alone (at different depths).

Thanks.

Keep in mind that White Balance is distance and depth dependent underwater.

If you use a white card, try and make sure it is 3-5 feet away from the camera when you do the white balance and re-do it when yor depth changes by more than 5-10 feet.

I have found that sand and/or a diversely colored coral head at the proper working distance works better than a white card held too close to the port.

Tanks also make good white balance reference marks as they are pretty neutral.

[...] with a white card, manual white balance should give me a more accurate reading. [...]

I agree, but I would like to separate the process of determining the correct color temperature from the post-processing. A white card will always give you the best reading on the white balance and in an ideal situation (shooting raw, have somebody to hold the card etc.) that is the way to go. Then it is just probe your card during raw import and you are set. I more realistic situations (still shooting raw, but no white card or willing buddy available), I find it easier to go with Jeremy's suggestion to use corals, tanks, fish scales etc for white balance.

My comment on the "cloudy" setting is mostly geared towards those not shooting raw. Then you are best served with getting the white balance as close to reality as possible inside the camera to minimize the amount of corrections done on the jpeg later on to avoid clipping regardless of how the correct color temperature is determined.

Jeremy and Dunadin,

Well noted. Thanks.