Taking Underwater Pictures With Your Camera's Built-in Flash

One of the most disregarded features of underwater housings for compact cameras is the ability to fit a flash diffuser to the housing and use the camera’s built-in flash as a light source.

I regularly see Facebook pundits of varying knowledge levels advise folk with newly bought cameras and housings to immediately add strobes or video lights to their setups. While a strobe on a good arm system adds more capability to the kind of pictures you can take it’s not a must have for all types of underwater photography especially when you are just getting started. I was several years and two cameras into learning underwater photography before I bought my first strobe.

Here’s Anne using a Canon S95 compact camera in a Canon brand housing fitted with a simple diffuser so that she can use the camera’s flash.

If your camera has a built-in flash and your housing is one that has a window for the light to pass through with a diffuser to spread and soften it, then you can achieve a lot without adding any accessories.

Not all brands of compact camera housing allow you to use the built-in flash. If you are on a limited budget it’s wise to avoid those housings as you’ll have to buy some sort of external light source as soon as you want to take pictures without using sunlight.

This image of a nudibranch was taken during last year’s Red Sea Photo Camp with a Canon G9X MkII in a Fantasea housing using the built-in flash. The Fantasea housing comes with an excellent diffuser which clips on near the end of the housing port. This reduces the amount of shadow caused by the port and softens the light so it isn’t harsh when used close to subjects.

As well as being a cheap way to get started taking pictures underwater, having just a camera and housing on a dive is less cumbersome and adds less task loading. That’s important to bear in mind when you are just starting out in underwater photography.

Despite being less powerful and having much narrower beams than external strobes a built-in flash still has the ability to ‘freeze’ movement in a shot in areas that they light. This puts them ahead of video lights in situations where the built-in flash has the coverage needed for your picture.

A black and white spotted moray eel

This picture of a moray eel in Bonaire was taken using a Canon S95 in a Canon housing (as pictured above being used by Anne). It was during a night dive and I used a small torch in one hand so I could see and the camera focus but the image was lit by the flash.

Not every picture can be lit using built-in flash even if your housing lets you use it. Wide angle underwater pictures will usually need more power and spread than the camera’s flash can provide and if you are using a wide angle wet lens it’s likely that the built-in flash will be blocked by the lens.

To light a picture using the camera’s flash you’ll need to be close. The area covered by the flash broadens as you get further from your subject but the power of light is diminished very quickly underwater so you’ll find that even with the camera flash set to maximum power you have to be almost on top of your subject.

The Olympus brand housings for their TG5 & TG6 Tough cameras have flash diffusers built-in and the lack of a protruding lens port means you can get close to subjects like this lizardfish without the light being blocked. But get too close such as when using the Microscope mode or Super Macro focus setting and you may find that the subject isn’t in the spread of the flash.

Getting too close may mean the thing you want to photography will be in shadow where the light is blocked by the port of the housing. It can take a bit of practice to understand the kind of picture achievable and the technique required.

You need to get close not just because the light doesn’t reach far but also to avoid backscatter. That’s the speckling you get from light reflecting off sand and debris in the water.

This shot of a bullhead under a pier in North Wales was one of the first pictures I took underwater in the UK using a digital camera. The camera in question was the excellent Fujifilm F30 in a Fujifilm housing.

I recommend you set your camera flash’s output manually if possible. This can be done with most compact cameras in the less automated modes such as aperture or shutter priority and manual mode. It’s possible to adjust the exposure of your subject by changing the output of the flash but also by changing the distance to your subject and by changing aperture size (f number) and or ISO.

Housings for interchangeable lens cameras rarely allow you to use a flash attached to the camera as a light source but the earlier Olympus branded housings for cameras such as the EPL-3 that I used to have did and they still show up on the used market.

Hopefully this blog will have been helpful for you. If you’d like to learn more about underwater photography we run courses online and workshops in the UK and overseas. We are also an equipment dealer for a wide range of brands including several housing manufacturers. Email info@alphamarinephoto.com with any enquiries or use our contact form to get in touch and sign up to our newsletter at the same time.

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