Underwater Strobes

Let’s start with a simple fact: you can’t take photos without light. I know, this isn’t a huge surprise for most people. But this has a lot of implication for underwater macro photography. What light you have is usually weak and it’s a funny blue-green color. There are just a handful of ways to counter this: shallow dives with an adjusted white balance, a handheld dive torch, a camera-mounted wide-angle video light (or several), and strobes.

My Inventory

I own 3 different strobes.

Sea and Sea YS-01. This is a small strobe with not a lot of power. I own only one of these and have for quite awhile. It’s great for underwater macro with a compact like my trusty TG-5 and TG-4. Its size is good to add on to my camera setup without adding much weight or bulk, and as my blog readers will know, small components are the name of the game when I take the compact on a dive. However, the strength of these isn’t so good for wide-angle.

Sea and Sea DS-02. These are my usual strobes for diving with my Lumix G9. They have medium-strong power. I’ve had to replace a couple of them over time because of corrosion in the battery compartment. They work awesome for macro if I use a dome diffuser and put then right up along the sides of the lens. These work well for wide-angle if you use two of them and you’re 2 meters or so away from the subject.

Scubalamp P53 Pro. These are my new video lights with a strobe capability. I added these earlier this year. They’ve been a bit of a trial to use just as strobes, but they are great video lights. They are heavy and need some flotation in water which isn’t much of a problem with a wide-angle setup and a huge glass dome but they’re very negatively buoyant on a macro rig.

Diffusers

Diffusers are a mixed bag of results, so you need to give some thought on when to use them. They’re a piece of plastic that fits on the front of the strobe. The idea is that they bounce the light as it goes through them.

So instead of having all the light come from one direction, it’s like having a bunch of mini strobes in many directions. This reduces the dark shadows and bright highlights in a photo that’s not quite as dramatic. This also had a side-effect of reducing some of the backscatter in your photos.

Diffusers also increase the angle that is illuminated by the strobe. I think it’s easier to shoot with diffusers since you don’t have to be as precise with where you aim the strobe.

However, diffusers have one downside: they reduce the total amount of light reaching the subject. This is around 1-2 camera stops which is a small limitation in how you shoot.

Diffusers come in flat or round shapes. The round shapes bounce the light in even more directions.

I have a set of Carbon Arm round diffusers for my DS-02 and I use them for macro. I don’t user a diffuser with the YS-01 although I’ve tempted to buy a dome diffuser for it. The P53Pro comes with a flat disk diffuser that fits under the front ring and I use those.

Signaling Strobes

There are 2 ways to signal strobes to fire: fibre optics and electronic cables.

I haven’t used electronic cables because they require that you have a hole, called a bulkhead, in the housing to put the electrical connection.

All of my shooting is done with fibre optics. They’re just a long piece of fiberglass with a plastic coating and some standard plugs. When light shines on one end, it shines out the other end.

For cameras that have a built-in flash–TG4/5/6 and my older EM10MKII– housings have holes right in front of the camera flash to hold the fibre optics.

For cameras that don’t have a built-in flash, you use a miniature LED flash, called a flash trigger, that fits into the camera’s hot shoe.

The strobes themselves have a plug for the fibre optic and a sensor that can tell when light comes through the fibre optic.

Strobe Layout

Single Strobe

For macro, you can easily use one strobe. You can experiment with distance from the camera body and light angle. This is a pretty easy setup to shoot with.

For cameras with a port, place the strobe on a medium-length (10-20cm) arm in the center of the housing so that it reached out over the end of the lens port. Point the strobe down.

For compact cameras, you can mount the strobe directly on the housing or on a small (5-15cm) arm for a little bit more flexibility.

Twin Strobes

I put my strobes up against the port at 9-o-clock and 3-0-clock and facing inwards a bit, maybe 20°. The diffusers are about even with the end of the port. This is more about getting the arms to work than the strobe and I don’t put too much thought into it unless I have extreme amounts of backscatter or I’m doing some weird style of shooting.

If I need to fit into a smaller area, I’ll move them up to 10-o-clock and 2-o-clock like Mickey Mouse ears. That lets me slide the lens front into smaller areas sometimes.

If I’m shooting a long-distance macro shot like little fish (blennies being a huge favorite), I’ll move the strobes out away from the lens port maybe 15-20cm. That limits the backscatter.

Free-Range Strobes

I know several photographers that mount strobes on small weighted tripods so that they can place them anywhere they want. They either keep the strobe connected via fibre optic or they have a fibre optic cable that plugs into the strobe and has an exposed fiberglass end that will catch the light from their on-camera strobe.

Troubleshooting

I’ve had days where I was not happy with my strobes. There are many things that can go wrong, and when they do go wrong, you shoot black photos. I have a lot of these on my network storage drive. I’ve seen my wife lay her camera down on the sandy bottom and swim away from it and I’ve felt like that myself.

Is the Strobe Flashing?

Hold a hand in front of the strobe to reduce noise from other lights and take a test shot. You should see the strobe fire into your hand. This is part of my pre-dive camera setup routine. If the strobe doesn’t fire, then the rest of the troubleshooting tests apply.

If the strobe fires but your photos are still black, then it’s one of 5 things:

Camera is set to use TTL but strobe is not. Easy fix is to set the stove to TTL mode and see if that exposes the photo properly. Harder fix is to check the camera settings to turn off TTL. TG4/5/6 calls this “RC” (remote control). Lumix calls this “Flash Mode”. Also one warning here: I don’t know of any flash triggers for Micro Four Thirds that do optical TTL.

Camera is set to “second curtain”. This is where the flash fires at the end of the exposure. In some cases this will mean that the strobe fires too late. Try first curtain and see if that works.

Shutter speed is too fast to “flash sync”. Set shutter speed to something like 1/125. Most strobes can’t sync faster than 1/250.

Camera exposure is too dark. Bump up the ISO to 400, appetite to F8, and shutter speed to 1/125.

Lens cap is on. We’ve all done it before.

Is the Camera Flashing?

If the strobe doesn’t fire, the first thing to check is if the camera is making a flash. Most of the time you can do this by removing a fibre optic cable and watching the now-empty hole while you take a test shot.

If the camera won’t flash, then there are several reasons why.

Camera is set to “quiet mode”. This turns off the shutter noise and the flash. Great for wildlife photography, bad for underwater macro.

Flash trigger is not turned on, doesn’t have batteries, or isn’t seated properly in the hot shoe.

Flash is set to “automatic”. Setting it to “fill-in” forces the flash to fire regardless of how bright the photo exposure is.

Is the Fibre Optic Broken?

This is very common, they don’t like much abuse. Check the connectors for obvious damage. Pull the plug off of the stove, fire a test shot, and see if you get a flash coming it of the cable.

Always carry extra fibre optic cables. Swap them out and see if that fixes the problem.

New Batteries?

Strobes seem to get schizophrenic when their batteries are low. My DS-02 need the flash power turned down when the batteries are half used, otherwise they don’t fire at all. Changing batteries fixes this.

The Backup

I always have a focus light of some kind on my camera and I try to carry a cheap video dive torch when I dive. In instances where I am having troubles with my strobes and I can’t figure it out after a couple of minutes, I’ll switch to using torches and keep the dive going. Things like that are usually better to sort out on the surface. Best to keep calm and carry on with taking shots.

See you underwater!!!

–Mike

To Tray or Not to Tray

A friend of mine messaged me the other day:

Checking with you, I’ve just bought a TG-5. So can I start shooting UW already or I need to add on any “lens”?

You have housing?

Yes, I’m on Ikelite housing.

For macro, you’ll need a light source. Also for wide-angle but you can also go without.

I have a video light, no budget for strobes yet. 😅

That’s ok. How do you mount it? Check out my blog post for TG5 setup here: https://underwatermacro.blog/2019/01/03/my-tg5-setup/

My housing will only reach next week, will send you a photo after I have mounted it. Also, about the tray: single handle & double handle, which is better?

Honestly, none. Best is a cold shoe mount on top of the housing. Trays are good for a couple of things. To mount light arms. For double hand holding on the housing to steady during wide videos. For a shutter trigger. For when you can’t fit your hands around the housing.

And they’re bad at some things. Having to reach further to reach the shutter. Making a wider camera that you can’t fit into spaces for macro. Getting hung up on your dive gear.

My G9 has left and right handles because it’s a bigger camera.

My TG5 has a handle on the right side because it holds a trigger. Makes it easier to fire a shot without twisting the camera. I took off the left side handle because I don’t need it to mount lights and because it makes the camera wider. If I need more lights and versatility, I’ll use the G9.

TG5 is my light travel and “exploration” camera. I want it lightweight and small.

The trick is: know where you are good and where you have to trouble and optimize the camera for your style. I will tell you this. A good photographer with a TG5 and a handheld dive torch can always do better than a poor photographer with an expensive camera with all sorts of shit hanging on it.

One thing that you do want to add is a lanyard. You can see mine in the photos. I don’t like how long it is when it’s clipped off. I just clip it when I’m descending and ascending. During a dive I undo the short clip and hand-carry it by grabbing the handle with my right hand. I either put it along the right side of my body, in my hands crossed in front of me like a tech diver, or underneath my crotch. 😁

Depends on what I’m doing at the time: hunting, traveling, waiting, etc.

Noted. Will read through your blog & digest as much as I could. Thank you so much for your advice.

See you underwater!!!

–Mike

Gear Optimization

Always keep working on your gear and optimize it to take better pictures.

How to Optimize

After every dive, I ask myself a couple of questions:

  • What pieces of my gear did I have problems with?
    • Takes 2 hands to operate?
    • Have to adjust several times to get positioned?
    • Fell apart while I was swimming?
    • Was so annoying that I wasn’t shooting relaxed?
    • Increased my breathing (SAC) rate?
  • Is there anything that I didn’t use that I can safely get rid of?
  • What non-shooting tasks did I spend the most time on, and can I find a way to reduce this time?

There are 3 key things that I am always trying to optimize: Getting setup for my first shot of a subject, getting that first shot right, and getting faster repeat shots.

Time to First Shot

What I’m looking at here is the time that it takes to go from swimming and hunting to set up for a shot. And then the opposite: to go from shooting to hunting for more subjects.

My Techniques.

Learn to hunt. Hunting is the biggest non-shooting time that I have during a dive. Anything I can do to locate subjects more quickly vastly improves my shooting time.

Control your clips. Clipping and unclipping your camera takes time. Experiment with holding it by hand on a longer lanyard. Experiment with different positions of carrying. Experiment with different clip-on points (I use the right shoulder d-ring).

Torch. You’re usually hunting for subjects with a torch. When you find a subject, you have to transition to holding a camera. I normally use a simple torch with a bolt snap (dog clip) tied on the end of it. I do one of three things to switch to a camera: clip the torch to the camera on the lanyard, clip the torch to my right shoulder d-ring, or set the torch on the ground to mark the subject so that I can find it again.

Take a quick peek. Have a good look at the subject before you place your camera. This can tell you what the best shooting angle is. Positioning and repositioning yourself takes a lot of time, so try to get it right the first time.

Camera placement. I find that when I shoot supermacro I spend a lot of time trying to get the lens in the right place for the subject. Then adding a 45° viewfinder makes this even more difficult until you get used to it. There are several tricks to this. If you use manual focus or back button focus, set up the camera at the same focus distance. If you’re using autofocus, get the camera in position but further back, use autofocus to get an initial fix, find the subject, move into the subject, and refocus. You can also set focus lock and move the focus in closer if you want to. Memorize the area around the subject to use as landmarks so that if you see the landmark you know which way to move the lens.

First Shot Accuracy

By this, I mean that when you take the first shot it is exposed properly and in focus.

My Techniques

Remember your settings. When you set up your camera before a dive, use the same settings for exposure: aperture, shutter speed, ISO, strobe positioning, and strobe strength. If you’re using manual focus, get your first focus fix on a test object that is approximately the same distance away from the lens as your “typical” macro subject.

Take a test shot. As soon as you descend, take a test shot of a rock or something else to verify your exposure settings.

Use a viewfinder. For some housings, 45° viewfinders are worth their weight in gold. They allow you to see exactly where your focus is by angling the image upwards so that you can get closer to see your picture.

Turn on focus peaking. This setting gives you a zebra stripe in the viewfinder for areas of the picture that are in focus. This drastically increases your accuracy in placing the focus.

Stabilize your camera. By anchoring your hands and elbows, you can keep the camera from shaking.

Breath control. When you breathe out fully, there is a natural pause before you start to breathe in. Also there is a smaller pause at the top when you fully breathe in. These pauses are good for shooting photos and for shooting firearms. A more advanced version makes mini-pauses in the middle of the breath. Don’t hold your breath for longer than 5 seconds because it makes you shake.

Handle with trigger. A shutter trigger reduces the amount of camera shake and “wrist twist”when you take a photo. Both of these mess up your framing and your focus point.

Time to Repeat Shot

The last optimization is to reduce the amount of time between shots on the same subject.

My Techniques

Focus lock and manual adjustment. If you’re skilled at this, you can fire multiple shots very quickly when you’re on a subject. You can practice this on land before you get in the water.

Faster strobes or no strobes. Strobes use capacitors to hold electricity and discharge it quickly to make a flash. Filling up those capacitors takes time. Better strobes have a shorter recharge time. Better yet, try shooting without strobes and use a video light, handheld torch, light ring or natural light: they are faster techniques.

Handle with trigger. Triggers are fast when you want to repeat a shot.

See you underwater!!!

–Mike

TG4/TG5 in Microscope Mode with Sea and Sea YS-01 Strobe

This is a very common gear combination and has proven to be one of the biggest pains in life to get this working.  It shouldn’t be this hard.  I’ve seen a diver throw their camera on the ground and swim away from it because the strobe wasn’t doing what they thought it should.  I picked the same camera up and took pictures, no problem.

There are 2 core problems:

  1.  The settings you need are poorly document and are not intuitive by any means.
  2. The the camera and flash use optical TTL which most people don’t know even exists.  I myself had to experiment and reread old forum posts about different models.

Optical TTL is an interesting thing.  Most people know electrical TTL which uses waterproof electronic wires between the camera and the strobe.  In optical TTL, the camera turns on its own built-in flash, monitors the exposure that it’s shooting, and when it has received enough light, it turns off the on-board flash.  The strobe turns on when it receives light via the fibre optic cable, and turns off when there is no light coming through the fibre optic cable.  The signaling between the camera and strobe is a simple on-off instead of pre-flash and monitoring that most people are used to.

The Camera Setup:

Turn on TTL

Inside the main menu, second camera icon, choose “Accessory Settings” and set “Remote Flash” to RC.  This is an abbreviated form of “Remote Control”.  This turns on optical TTL.  Why they can’t call it TTL, I don’t know.

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Second Camera Screen, Accessory Settings

 

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Use the Right Flash Mode

Inside the quick menu (from shooting mode, hit the lightning button to the right of “OK”) there are 3 modes that you can use.

“Fill” works to turn on the strobe but without TTL: you manually adjust the strobe power.  “Fill” means that no matter what the camera meters the scene at, it should fire the built-in flash anyway, and this will trigger the strobe to fire.  Fill is designed to add light to foreground objects in an otherwise-lit scene such as people in the shade with a sunny background.

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Fill Mode

“RC” Uses TTL and sends the start-stop signal to the camera’s built-in flash. “RC” only appears after you turn on “Remote Flash: RC” in the main menu as described above.

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RC Mode

“Slow” fires the flash and keeps the shutter open, this gives more time for light to reflect off the background.  Think of it as “front curtain sync” if you’re used to flash on land.  I was unable to tell if the camera uses TTL for “Slow”.

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Slow Mode

The Strobe Setup:

Use TTL

Turn the power knob to TTL.  Done.

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Set to TTL.