Which is best – Underwater Flash or LED light?

[vc_row][vc_column][vc_column_text]underwater flash or light
At FOTOGRAFIT we have a large variety of customers. Ranging from the absolute beginner to the professional commercial dive company. But one of the most common subjects I talk about is underwater light. And I´m often asked about which is better – underwater flash or LED lights.
And the simple answer is… well… there is no simple answer!

It simply needs an explanation…!

Photography lighting is complex – Under water lighting is even more complex
I got my first job as a photographer in the late 80´s. The company I worked for had several buildings with studios, and where I worked, we took pictures of individual furnitures… heavy large ones…  and at a high pace…!

We did not use flash in this studio. In fact, the light didn´t change much from take to take… but I remember one day, the Studio Manager sent me down the road to the other studio we had… this was the larger of the studios, and here they did lots of different set-up’s. And they used flash. I was asked to help one of the other assistants, and I remember being very eager to figure out everything about the cool gear in this studio. So I asked lots of questions.

When the set-up we worked on was ready for shooting, my boss came in, and started to tweak all the lights we had set up, and he measured them with a flash meter. I looked in awe and was asked to prepare the cassettes of film, and to assist him during the exposures.

There was silence during the shootings. But I decided to ask my boss: “What is the difference between the Constant Light we use in the other studio – and Flash we use here?

SILENCE … absolutely no reaction from him at all… he just stood completely still, looking at the set-up for several seconds. Then I heard a thin voice belonging to the other assistant who was standing behind me: “there are many reasons… I can tell you later…”

The boss gave a little sigh, looked at the assistant and said. “Thank you”…

That was my first experience with that question about Flash or Constant Light – but despite the answers I later got from my colleague, it took me several years to really understand the many benefits of using Constant Light at one point – and flash at another.

You see… light isn’t just light.

Flash and Constant Light can be both “hard” and “soft” and appear in many ways, just by adding small gadgets like diffusors, optics, shades, barn doors, color filters and in combination with each other.

Only a few people ever get the full insight into lighting – and using light under water ads an extra level to the complexity.

The good news is, that underwater light is becoming cheaper, more versatile and smaller – and the minute you get your first light, you can start playing with it and for every dive you do with a light, you become more and more skilled – and you will not feel it as a burden to learn.

LED lights gets smaller and less expensive
I think I was one of the first people around to start using LED light for underwater photography on a regular basis. I found it very natural due to my history with constant light in the photo studios and I even went on a Liveaboard for a week, without bringing a flash! (tricky… but fun).

Years back, when LED was just starting to come out, they were very expensive.
But then the “Light & Motion SOLA 600” got released and completely changed this. Nobody had seen the intensity of a LED light in such a small unit before.
I was distributor of Light & Motion in the Nordic region at the time, and hence that, I took this light around and showed it to people and during this time I used it a lot in my own photography and when I did underwater photo workshops.

I quickly realized, that new underwater photographers – and even people who had been taken pictures under water for years, had a lot to benefit from being able to see what they were doing with their light. Prior, most people based their entire photography on one single setting that they were comfortable with, and did all kinds of photography with that particularly light setup. Many of these photographers got fairly good exposures and sharp pictures, but the artistic quality of the photography (and here I mean – the creative and artistic value by playing with the light) was often not very high.

Today the quality of the LED has increased dramatically – and at the same time they are smaller and a less expensive. So the gab between LED lights and flash is getting smaller.

But there are still some important differences between the two light sources, which you need to be aware of.[/vc_column_text][/vc_column][/vc_row][vc_row][vc_column][vc_custom_heading text=”How Underwater Flash & LED compares” use_theme_fonts=”yes”][vc_column_text]At FOTOGRAFIT we have a large variety of customers. Ranging from the absolute beginner to the professional commercial dive company. But one of the most common subjects I talk about is underwater light. And I´m often asked about which is better – underwater flash or LED lights.
And the simple answer is… well… there is no simple answer!

It simply needs an explanation…![/vc_column_text][/vc_column][/vc_row][vc_row][vc_column][vc_row_inner][vc_column_inner width=”1/2″][vc_column_text]

Underwater Flash:


  • Can delivery high output power very fast.
  • Has a fast exposure (short exposure in fact)
  • The size (when equals similar power from LED)
  • Long duration of batteries – can do many shots.


  • Can´t be used as dive light
  • Can’t see the result before you have taken the picture
  • Can´t see the power of the exposure before the shot
  • Often lots of controls – need to spend long time on learning how it works.

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U.W. LED – constant light


  • Can double as dive light
  • Possible to see the result before doing the exposure
  • Can be used for both video and photography
  • Often easy to use and simple controls


  • Not as powerful as the flash.
  • Difficult to get large depth of field on macro shots due to the weaker light.
  • Might scare the fish
  • Difficult to freeze moving targets – like fish – due to the lack of fast shutterspeed.

[/vc_column_text][/vc_column_inner][/vc_row_inner][/vc_column][/vc_row][vc_row][vc_column][vc_text_separator title=”Let´s look deeper into the details”][vc_custom_heading text=”The Flash:” use_theme_fonts=”yes”][vc_column_text]D2000 flash

The flash is a great tool. It can accumulate a high amount of energy from the batteries, and fire it off in a glimpse of a second.
Flashlights used to be a lot smaller than the constant lights, but LED lights has become smaller, and in the recent years most LED lights are in fact smaller than most flashes. It is still possible to get small flash units, that has a high power output. This means, that if you need to do close up macro in tight spaces, a tiny flash could be the right tool for you.

When the flash exposes, it shoots a fast glimpse of light. This glimpse can be as fast as 1/1000 of a second and that is fast. This means that a small fish that moves will be ‘frozen’ in the picture when hit by the light. And this is very handy for the macro photographer that likes to shoot pictures of small fish which constant moves. (I don´t… I hate the waiting it involves) 😉

As mentioned in the matrix, the lack of Constant light forces you to make a couple of test shots, in order to check out the actual power of the light, and the angle you have chosen to use it from. This takes time. Particularly when you want to play with the light angles all the time, and it is a constant process through out the dive, but once you get to know your flash – this process goes fast and become routine.

The flash also needs a trigger from the camera in order to go off. In the old days this was a thick electrical cable, which often had problems with eroding.

Today the most common is to use the internal flash of the camera, and to let it hit a fiber optic cable, which is then connected to the flash. This cable is lighter and can be very long. And once you get back on land, you can dismount it from the camera housing and take your equipment apart straight away. With the electric cable you had to rinse and dry it first. The backside of using fiber cable with a flash is, that it needs the camera flash to go off in order to trigger the underwater flash, and this will drain the battery.

The newest solution to that problem, is a flash trigger. A small LED unit that is mounted on the camera inside the housing, which then make a LED glimpse that then triggers the flash. Quite smart – and will improve and be more common during the next years.

[/vc_column_text][vc_separator][vc_custom_heading text=”The LED Light: (Constant light)” use_theme_fonts=”yes”][vc_column_text]Venom 38 Underwater LEDToday divers mainly work with LED light. There are other lights out there (HID/Halogen) but no one beats the LED in price VS. quality.
The LED units use very little battery power compared to lights just a few years back. And even when delivering a high intensity of light they can light for a long time. So where we saw lights of 200-600 lumen earlier, 3000-6000 lumen are neither uncommon nor particularly expensive

As mentioned before, playing with the light in different angles and mixing it with both sun-light or the light of your buddy, is quite hard. At least unless you have a LED light and are able to monitor the LCD screen on your camera and see the result “on the fly”. In fact, I can tell you that you are not able to be just as creative with your flash, as you are with a constant light. The reason is, that as divers, we move a lot due to changing buoyancy, current and waves, so the subject changes all the time, and we have to change the light with it.

With the high lumens of the lights today, it is possible to shoot with lower ISO levels and higher aperture (chip sensitivity and hole size through the lens). Also the cameras are changing a lot these years and are becoming more light sensitive, which is great news for those who like to use a Constant light source.

One of the last things I need to mention is, that you can´t make video with a flash. And as most cameras today do equal good video and photography LED light is essential. So in fact, lots of underwater shooters bring both a complete flash system and a set of LED lights.

What to choose?
As you might guessed, there are lots of decisions to make when you purchase your first light or upgrading. Do you want the easy handleable LED light – or the more powerful and fast flash. Maybe you think you will never make video – and only want to focus on photography. But the thing is, it is also possible to do great photography with constant light, so the smartest solution would be a light that contains both flash and LED light.[/vc_column_text][vc_custom_heading text=”The combined Flash and Light ” use_theme_fonts=”yes”][vc_column_text]The Symbiosis – combining Flash and LED

Diving light that has both LED light and flash
Symbiosis diving light that has both LED light and flash

Until now it has not been possible to get a unit that has a high quality flash – and at the same time a LED light that was good enough for making prober video. But with the constant evolution of LED light and the always increase in battery power, this is changing.

i-Divesite has produced a unit that has melted both functions into one unit and named it: Symbiosis.

The Symbiosis SS-1 is one of the fastest re-charging flash units on the marked at a very affordable price – and the  Symbiosis SS-2, has a LCD screen for easy monitoring of the functions.

We have a tested the Symbiosis and you can see first results here

You can read more about Symbiosys Lighting System on the FOTOGRAFIT website.[/vc_column_text][/vc_column][/vc_row]