Future of strobes? LED?

Hi Guys,

I was looking for a third (remote) strobe. The seacam remote trigger looked pretty cool, but works only with seacam strobes... and for the price of one seacam, I can get 4x new Z240 strobes. In my opinion over 2000 euro for a strobe seems pretty much ridiculous.

So I checked subtronics, also a german, aluminum housed strobe. Apparently they make LED strobes! Any comments on this ?

Its called the Subtronic Sirius.

You can buy a remote slave trigger.

It allows you to activate the strobe you have at good distance.

2 examples:

http://reefphoto.com/shop/index.php?main_page=product_info&cPath=135_68_64&products_id=2574

http://users.telenet.be/triggerfish.slave.unit/

The sirius is nice but not very bright, the GN is only 5.6 compared to 11 or so for YSD1.

I am not sure about the duration of the flash, the translation says it is "arbitrary" and the number of guaranteed flashes is 1000, I assume that is a battery capacity not a full on design issue, if it is then each flash cost $1.

Bill

Hi, I was wondering if since 2016 anyone has actually purchased and tried the Subtronic Sirius and if they any feedback?

I haven't used the Subtronic, but I just ordered the Weefine Smart Focus 3000, which has a LED strobe function. I am going to use it as a focus light with the occasional use for snooted macro, as my strobes have no pilot light to properly aim them with a snoot. No experience yet, but I will report back after testing (if I don't forget). Weefine also makes a Smart Focus 6000 which has a much stronger strobe output. It is advertised as GN16 (on Land I assume), which is not that much worse than the smallest Strobes (S2000 has GN20). There is a pretty good comparison review, that shows what that means in real life.

The TL:DR is: At this moment LED strobes work for macro, but not for Wide Angle. Also, because of the long flash duration exposure works a bit different and you can't use the flash to stop motion.

However, if technical advances continue the last point may become a moot point. If the LED Strobes were bright enough, long enough sync speed would not matter anymore. Let's see what comes first: Global Shutter or incredibly powerful LED Strobes.

My strobe experience in my 10 or so years of underwater photography is that the xenon-tube strobes are the weakest members of the camera team. This is because either the electronics fade away or the xenon tubes burn out.

Repairing a strobe is an international undertaking, requires diplomatic skills plus the persistence of a drug addict, as few or no shops are trained to do the work, the entire electronics of the strobe have to be replaced, spare parts are not available, etc. Excuses, excuses, no results, as I have been unable to have a strobe repaired in Tokyo, Manila and Los Angeles. Plus underwater strobes are grossly overpriced, in marked contrast to the regular ones. On and on the sad story goes.

As strobe failure has semi-ruined the photographs of some of my overseas dive trips, I now replace my strobes every two years, whether they need it or not, as the cost of the trip and the frustrations of bad strobes far outweighs the cost of new strobes.

A couple of years ago, when three top companies pulled their xenon-tube strobes from the market, I suggested in these pages that an LED strobe, preferably a smart one, would be welcome. It still is, only more so.

http://wetpixel.com/forums/index.php?showtopic=62030&hl=%2Bled+%2Bstrobe+%2Bin+%2Bour+%2Bfuture%3F

My strobe experience in my 10 or so years of underwater photography is that the xenon-tube strobes are the weakest members of the camera team. This is because either the electronics fade away or the xenon tubes burn out.

 

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As strobe failure has semi-ruined the photographs of some of my overseas dive trips, I now replace my strobes every two years, whether they need it or not, as the cost of the trip and the frustrations of bad strobes far outweighs the cost of new strobes.

 

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Which is a BIG reason I use two strobes; many of my pix would be adequate with just one, so this way I have a spare so as not to spoil a trip.

I'm a cave diver; so "two is one, one is none."

Yes, good reason to use two strobes, and better, three. Good idea. I now pack three strobes, as my two Inon Z240's dimmed at the same time while on a 10 day dive boat trip, no way to get replacements.

About LED's, one objection is that they burn out. LED's are being designed to be brighter and brighter, which means they are more resistant to overheating; even so they will burn out, just like xenon tubes do. The solution may be to design the strobe with a replaceable LED, just like replacing a burned-out flashlight bulb in ancient times.

In the long run, ???, I predict that LED will replace current strobes!

As John Maynard Keynes says, "in the long run we are all dead". I think it will be quite a while to get LED output "in a short pulse i.e. ms) that is close to the power of a discharge tube. What will happen more likely is that more people will use CW LED lighting for UW photography. LEDs have taken over a lot of studio lighting tasks and as higher ISO capabilities of cameras get better and LEDs get brighter this should move to UW. Stopping action is a completely another story. Look at the size of a discharge tube and compare to an LED. The problem is obvious

Bill

To add to the Xenon Strobe vs LED discussion:

Of the widely used underwater strobes, only two of the three popular ones are now available, as the promised new Retra strobes have not materialized, leaving us only Inon and Sea&Sea. The Inon Z330 is hard to come by and excessively priced, leaving the newer Sea&Sea YS-D2J as the available choice. But the YS-D2J seems to be regaining our confidence, despite the burn-outs of some of its previous models posted here. The YS-D2J is not inexpensive; I currently use two and I keep my fingers crossed. (I did not mention Ikelite as their excellent strobes use sync chords with no TTL. Synch cords are widely known to be guaranteed trouble. Note to Ikelite: Please hurry up and give us a fiber-optic triggered strobe.)

Problems inherent in xenon flashes include the high temperature and high voltage involved (about 500C and 350V) with the need for high performance circuits and prompt cooling. The duration of an external strobe flash is not controlled by the camera's TTL system so that underwater TTL photography requires an external added-on TTL control device. As each camera maker has its own patented TTL signals and circuits, this further complicates the design and use of an added-on TTL device. The result is that the problems of added on TTL circuits are legion, as discussed in these pages on a recurring basis.

Previous commentators cited some physical advantages of the xenon flash over the LED. These reduce to engineering problems of how to prevent voltage pulses and heat from damaging the LED lamp. Progress has been rapid: The brightness of available LED lights keeps on increasing, they are now blindingly bright, and also hot, while their prices have dropped. The development of the COB (circuit on a board) LED architecture is an example of this progress.

Now needed is an LED strobe circuit to reliably produce the millisecond flashes needed to freeze motion. The goal for a new underwater strobe is an LED that will work reliably after thousands of, say 100,000, millisecond flashes, provided with cooling to prevent damage from overheating, plus smart on-board sensing to emit TTL metered flashes. The LED strobe should also be designed to be repairable.

An alternative to the LED strobe is to use the continuous light of one or more high intensity LED underwater lamps, to take advantage of the very high ISO and resolution of the new generation of cameras, so one can shoot with a fast shutter speed to freeze motion. To give one camera example, the Sony a7Riii has 42.4 megapixels with an ISO range of 40 to 102,400 with excellent image quality throughout most of this range.

Back to LED strobes: A relevant item of interest to be watched is the continually improving quality of cell phone cameras and their built-in strobes, a Darwinian force driving the evolution of cell-phone LED photo strobes, a force generated by the huge moneys spent by those addicted to their cell phone cameras.

The quality of the pictures taken with these small cameras keeps on improving and so cell phones are replacing pocket cameras. Will they one day become the standard for underwater photography?

It all adds up to a fun mix of new equipment capabilities, design problems, cell phone addicts, talented developers, dropping prices, and the needs of us underwater photo nuts. Stay tuned.

 

Of the widely used underwater strobes, only two of the three popular ones are now available, as the promised new Retra strobes have not materialized, leaving us only Inon and Sea&Sea.

It's somewhat inaccurate to claim that Retras 'have not materialized', as the last year's announcement specified May-June 2019 as the scheduled release date. While I have little doubt they'll slip a bit (or more than a bit), I don't think they're vaporware.

 

The Inon Z330 is hard to come by and excessively priced, leaving the newer Sea&Sea YS-D2J as the available choice.

Backscatter lists Z-330 at $650 and YS-D2 at $690; how is it that Z-330 is 'excessively priced'? Both are marginally less expensive than Retra (€655) or Retra Pro (€820).

 

I did not mention Ikelite as their excellent strobes use sync chords with no TTL

I don't own an Ikelite strobe, but it is my understanding that TTL is possible with them if you use an appropriate converter.

 

The duration of an external strobe flash is not controlled by the camera's TTL system so that underwater TTL photography requires an external added-on TTL control device.

My experience using TTL over fiber optics, triggered off the camera's built-in flash has been largely trouble-free. While an add-on TTL trigger would certainly be helpful, it is by no means required.

 

The brightness of available LED lights keeps on increasing, they are now blindingly bright, and also hot, while their prices have dropped.

They're still several orders of magnitude less bright than xenon flashes. Yes, powerful LEDs are available - but a Scubalamp V12K costs over two thousand USD, weighs over 3kg, and its battery is big enough to pose trouble with air travel; all of that for an output of 24000 lumen - keep in mind that you'll need over a million lumen to match a xenon strobe's prompt output.

 

An alternative to the LED strobe is to use the continuous light of one or more high intensity LED underwater lamps, to take advantage of the very high ISO and resolution of the new generation of cameras, so one can shoot with a fast shutter speed to freeze motion. To give one camera example, the Sony a7Riii has 42.4 megapixels with an ISO range of 40 to 102,400 with excellent image quality throughout most of this range.

While high ISO can work in a studio, where you control the ambient light, it is not a solution underwater where we need the strobes to overwhelm the ambient sunlight to produce vivid colors. Raising ISO can help with reducing shutter speeds (up until you run into flash sync speed limits), but the sensor will just ingest more of the blue/green tinged natural light, doing nothing for color reproduction.

 

Back to LED strobes: A relevant item of interest to be watched is the continually improving quality of cell phone cameras and their built-in strobes, a Darwinian force driving the evolution of cell-phone LED photo strobes, a force generated by the huge moneys spent by those addicted to their cell phone cameras.

The quality of the pictures taken with these small cameras keeps on improving and so cell phones are replacing pocket cameras. Will they one day become the standard for underwater photography?

A lot of the improvements in smartphone camera output come from increasingly sophisticated post-processing. Phone manufacturers target audiences of tens and hundreds of millions of consumers, and this allows them to sink immense resources into relevant R&D. By contrast, us underwater photographers are a tiny bunch, and our requirements are highly peculiar - I would not count on Googles and Apples of the world investing much effort on our part.

 

The basic idea is that us underwater photographers need equipment that is reliable, reasonably priced, and repairable.

'Reliable' and 'repairable' are somewhat contradictory goals. A repairable device needs to have accessible internal components and parts joined by detachable connectors - but every access port is a potential water ingress point, while every connector is a failure waiting to happen. A fully sealed unit with everything inside soldered together and buried in glue is more reliable, yet not at all repairable. As for 'reasonably priced', this is subjective - some people don't blink an eye at paying $3k for a Seaflash 150D, while for others a $365 Inon S-2000 is way outside their price range. Regardless, a tiny niche like underwater photography, particularly the high end of this niche represented by those who dive with handled rigs with dual strobes, will never be large enough to enjoy mass market economy of scale advantages that bring prices down.

 

Will smart, reliable xenon or LED strobes ever become available, and if/when they do, will they work?

The new Retra strobes appear to be moving in that direction. They're adding high-speed sync, which is almost unheard of in underwater strobes, and they're claiming to be proof against flooding the electronics and survivable against flooding the battery compartment.

 

Or better still, will the new LED lamps and high ISO cameras render add-on TTL and strobes obsolete?

Again, high ISO doesn't help you when sunlight, filtered through fifty feet of water, floods your image with blue or green. Your white light source must be brighter than ambient by a sufficient factor, and increasing ISO or exposure window does not help - on the contrary, the more you lengthen the pulse, the more energy you end up needing to dump out of your strobes. Can you imagine staring into a million-lumen continuous light? It'll burn out your retinas right through your closed eyelids.

I think Barmaglot does a great job of outlining all the reasons why LEDs aren't going to be matching the capabilities of strobes underwater any time soon. In my own testing, a YS-D2 is about 6 stops brighter on full power than the 14000 lumens Gates GT14. (And this is allowing for a 1/60s exposure with the LEDs).

And better ISO capabilities of cameras don't make any difference. The problem we're trying to overcome underwater isn't a lack of light -- it's too much cold ambient light. We need our artificial light to be powerful enough to outcompete the ambient light. Zenon strobes that output all their illumination in one very short burst do a much better job at this than LEDs that output light continuously. The amount of light an LED can output in the same time frame as a zenon tube is several orders of magnitude weaker than what a flash can do. LEDs aren't going to be replacing zenon flashes in our lifetime, if ever.

And better ISO capabilities of cameras don't make any difference. The problem we're trying to overcome underwater isn't a lack of light -- it's too much cold ambient light. We need our artificial light to be powerful enough to outcompete the ambient light. Zenon strobes that output all their illumination in one very short burst do a much better job at this than LEDs that output light continuously. The amount of light an LED can output in the same time frame as a zenon tube is several orders of magnitude weaker than what a flash can do. LEDs aren't going to be replacing zenon flashes in our lifetime, if ever.

While I generally agree it is a long way (if ever) to see LED lights replacing strobes, I think for certain types of UW photography the new brighter and improving LED lights are an option in MACRO photography which offer some advantages over strobing... In regards to reliability I think strobes for me have proven much more reliable than LED lights!

 

While I generally agree it is a long way (if ever) to see LED lights replacing strobes, I think for certain types of UW photography the new brighter and improving LED lights are an option in MACRO photography which offer some advantages over strobing... In regards to reliability I think strobes for me have proven much more reliable than LED lights!

Sure, for macro subjects that aren't bothered by strong continuous light in their face, I mostly agree, if you're willing to work at higher ISOs and get lower quality images than with strobes. Remember that for macro you end up having to shoot at rather narrow apertures -- F16+ on full frame -- and without a strobe to freeze action for you you also have to keep your shutter speed higher. Probably 1/100 at a minimum, unless you're limiting yourself to a tripod with a static subject. I think that easily puts you in ISO 800+ territory even with strong video lights.

LED lights are easier to snoot than a strobe at least, since you see where the light is falling.

I keep wondering if it might be possible to do macro focus stacking with continuous LEDs - lock focus slightly in front of the intended target, then shoot a high-speed burst while slowly moving the camera forward, and combine the resulting set of 20-30 images in post to cover the whole subject rather than a portion thereof.

 

Sure, for macro subjects that aren't bothered by strong continuous light in their face, I mostly agree, if you're willing to work at higher ISOs and get lower quality images than with strobes. Remember that for macro you end up having to shoot at rather narrow apertures -- F16+ on full frame -- and without a strobe to freeze action for you you also have to keep your shutter speed higher. Probably 1/100 at a minimum, unless you're limiting yourself to a tripod with a static subject. I think that easily puts you in ISO 800+ territory even with strong video lights.

 

LED lights are easier to snoot than a strobe at least, since you see where the light is falling.

I am not sure what lights you have tried but I would not be so critical for macro. As an example here I used a 1000 lumen light to get this 1cm shrimp (quite too transparent for strobo shooting!) with a M43 sensor (em5mk1) and 60mm macro set at f11, 1/250, ISO 200. M43 sensors usually give you a bit more flexibility for macro. Probably ISO 200 on M43 behaves as an 800 ISO on FF. However I get a reasonable DOF at the FF equivalent of F22 and certainly a plenty good shutter speed handheld.

I keep wondering if it might be possible to do macro focus stacking with continuous LEDs - lock focus slightly in front of the intended target, then shoot a high-speed burst while slowly moving the camera forward, and combine the resulting set of 20-30 images in post to cover the whole subject rather than a portion thereof.

I assume this might be possible with something like an EM1mkII and it's stacking functions. You might want to be on an underwater tripod though?