When I deliver my underwater lectures there are often scuba divers in the audience & the question I get asked most (usually after the lecture) is about lighting underwater. This is because I make a big thing about it in the lectures - for me it is one of the most important factors in capturing a good image, underwater or surface.
So, whilst I realise this article is irrelevant to most folk it does give me somewhere to point divers for my thoughts.
There is no doubt that a “eureka moment” in my development as an underwater photographer was the realisation that, in the face of all the other competing demands (diving issues, camera settings, composition) I had relegated lighting to the "sorted" list i.e. just apply lots of even light & you're bound to get an image! This is of course true & should be the starting point... but with thought you can get so much more.
After I decide a subject is worthy of the time (a big decision because I often take 10 minutes or more on a subject & a dive only lasts 60 minutes, so it had better be worth it) my mental lighting checklist is;
1. always shoot up towards the surface if possible. It makes your subject more dramatic & the view of the surface is both beautiful & orientates your viewer
2. make sure your viewer sees enough of the background to appreciate the underwater scene. There are exceptions of course, but for me this is true 95% of the time
3. whilst observing the direction of the ambient light (sun position) & emphasising this with your flash - be subtle. Over lighting is a dead giveaway, as are flash shadows. It destroys the ambience - your viewer should have no idea you have lit it artificially
4. try to light along the subject - this provides subtle shadows which emphasise contours & bring out a 3D effect
5. following on from the last point do not have the flashes on the same power setting. Real life is hardly ever like that - one side is more in shadow
6. constantly keep moving the flash position & your position. Digital images are free - take lots! I do this in the hope one will be good :-)
I've never formally written this list down before & I could go on. Suffice to say I now pay more attention to lighting than anything else... & the day I started doing this I think my images improved.
The underwater scene is often beautiful - show it to your viewer
Although there is no background in this shot I think the spotlight effect suits this gorgeous nudibranch
Showing the surface gives your viewer orientation
Firing the light along this Hairy Frogfish really shows why he gets his name
Always try to shoot upwards
I fired the light down from above this Common Seahorse. It’s important to try different lighting angles (& strengths) to get the most dramatic effect.