Strobes or Filters?

I am new to underwater photography although I have been using SLR for a long time. I will dive in Cairns and Fiji in November and would will use my Nikon D200. Right now I am researching on gears for D200. I read the article by Cheng, "Filters and Ambient Light Photography"

When I am in Cairns and Fiji, I expect myself not going deeper than 50 feet and do day dives only. I think I will use both a wide angle lens and macro 60mm. Do you think using a filter will be sufficient for clear water in Cairns and Fiji or still a better idea get two strobes?

If filters will be sufficient, what kind of filters should I get? I assume water over there will be clear and blue? If I still need strobes, do you have recommendations? I do not see myself diving in California nor anywhere very deep. I guess I do not need very powerful strobes.

Thank you very much for your suggestion.

Hi,

I think there are two answers to your question!

For wide-angle scenic pictures, or pictures of large objects (wrecks, schooling fish) filters will do a great job. Due to how quickly light is absorbed in water, strobes are used in underwater wide-angle to highlight objects close to the camera, whilst balancing the exposure with the ambient light in the background.

For macro subjects, you would typically use strobe light exclusively. This is in order to maximize depth of field by allowing a small aperture, and creatively to reduce the impact of the background.

Strobes cannot be used in conjunction with filters.

Of course this might all be wrong and you may find an excellent creative technique using filters for macro-but it is the conventional view.

Adam

Alex Mustard (Magic Filters) has some good advice about filters: the angle of the light is critical. I do seem to recall that a lot of the soft coral images from Fiji have been shot with strobes, though. Macro doesn't seem to be possible without strobes because a small aperture is needed. Some things are not what you would expect: the shallower you dive, the more powerful your strobes need to be, for instance. I really recommend practicing before going to such a good part of the world for underwater photography, so as not to miss the opportunities for great images. It's harder than an experienced photographer expects!

Tim

Thank for replying. Now I need to figure out which strobe I need to get and then practice in swimming pool before I go there.

I be suggesting that you look at getting both but get two strobes first and spend most of your time getting use to them. Keep in mind that filters like Mr Mustards Magic filters are cheap ($45aud) compared to a pair of new strobes so why not get a set of filters and play with them before you go.

You be kicking yourself if you did the Beqa Shark feed in Fiji with no strobes as they feed the Bull sharks and tigers at 30m. Depending where you go from Cairns to do the Great Barrier Reef will depend on how the water quality is. If you do days trips from Cairns you often go to lesser quality dive spots than you go with one of the Liveaboards. Using filters under these conditions would be frustrating and not recommended. Keep in mind that filters as stated before work well with clear blue water on large subjects like wrecks and large schooling fish and dont work for macro shooting.

Regarding strobes I like the Inon Z240's as they are small, powerful and dont weight much which is ideal for travel. Airline weight restrictions here in Australia have tightened up more so in the past month and they are out to make money from excess baggage. 20kg checkin and 7kg carry per two items (laptop and carry on bag) is strictly inforced at Brisbane international. Same with your domestic fligths checkin baggage to and from Cairns. Domestic you can get away with more carry on as they dont often weight them.

Regards Mark

A strobe replaces the unbalanced ambient light with a balanced local light source, and so will generally give better colour results then a filter and/or white balance. However the light from a strobe will dissipate after just a few metres, so is only good for subjects that are close.... simple solution, get as close as you can . Easy for macro, for wide angle, choose a very wide lens that has a close focal distance (hence why fisheye's are so popular)

However that's not too helpful for large objects such as wrecks... but then for wrecks, do you really want to return the colours back to "normal"? I think a lot of people get over anxious about getting a perfect white balance, removing all the blue or green hue from an image. I prefer the term colour balance, leaving the natural colour hues can sometimes add atmosphere and emotion to the end image.

I shoot with two Inon z-240 strobes, I find they are relatively light and small for travel, reliable and easy to use, decent power and recycle time with a give a good balanced light output, with decent coverage. Although the second strobe is a reasonably recent addition, whilst I do prefer the results a twin strobe set up gives, a single strobe will still serve you well and may be a little bit less of a struggle to begin with.

A quick cap on exposure for you, when using a strobe. As has been said, a strobe will only light relatively close objects, so you need to think of your image in terms of two stages i.e. objects that are close, and that will be lit by the strobe, and objects that are far away, that will be lit by ambient light only.

Ignoring ISO;

Shutter speed, will only have an effect on the ambient light, and so will control the exposure of the rear stage of your image (your shutter will always be open for longer then the flash of the strobe, so the full strobe power will always get through regardless of what you do with the shutter speed)

Aperture will effect both the ambient and strobe, and so will control the exposure of both the foreground and background of your image

Strobe power will, not suprisingly, effect the power of the strobe, and so will control the foreground exposure.

Hope that all helps

Cheers

Stuart

Typically, which of the two options would be best during a wall dive? I'm guessing a double strobe to add a brightly lit subject to the fore ground with a model or fish in the back ground?

Yes, double; one on foreground and second on model.

Shoot manual and adjust different strobe powers for foreground, model

Good tips, I am learning too. I have shot with multiple flashes (on land) Joe McNally style so this is making sense. Thanks!