RETRA Lithium-Ion Battery Pack

[Dave_Hicks]

33 minutes ago, Jerry Diver said:

 

Honestly, I don't understand the complaints about the pricing. It aligns with what other manufacturers charge for their proprietary battery packs.

 

 

How about an extra $400-500 per strobe on a $1600 USD Retra Pro Max? That's ridiculous for something that should be included in the base price. And that Retra Li-Ion pack is a monster. It's looks ridiculous and cumbersome as hell. Even an Ikelite looks sleek in comparison. 

 

Compare to the Backscatter HF-1 which I recently bought and am currently evaluating. It's $900 or $950 if you include a pair of the recommend 21700 Li-Ion batteries. That's better than half the price for a strobe that is more functional and in the same product segment of powerful WA capable units.

[Chris Ross]

8 hours ago, Walt Stearns said:

 

Since day 1 when Retra introduced their underwater flash system, we were advised to use Eneloop pro AA Rechargeable NiMH Batteries which individually have a battery voltage of 1.2 V with 2550 mAh / 3.06 Wh

 

Now with 8 of these batteries bundled together you then have 9.6 V, but your battery capacity is still going to provide 2550 mAh / 3.06 Wh.

 

Whereas with 8 EBL AA Li-ion batteries which have a battery Voltage of 1.5V with 2200mAH / 3.3 Wh individually are bundled together will then have a total voltage of 12V, yet the battery capacity for all 8 together remains at 2200mAH / 3.3 Wh. 

 

While it was advised to stay away from the latter, now comes Retra’s new Power Vault Li-Ion battery pack which is stated to provide 7.2V with a battery capacity of 5555.56 mAh / 40 Wh.

 

To me, this is a bit of a head scratcher.

That's not how it works,  the W-hr for each battery is additive.  The amp-hr capacity remains the same, but it is the same amps at a higher voltage which is more energy.

 

For AA Eneloop total capacity is 1.2 x 2.55 x 8 = 24.8 W-hr

for AA lithium it is 1.5 x 2.2 x 8 = 26.4 W-hr

 

The new battery pack is possibly using 4 x 18650 cells of 2770 mAhr capacity in 2 parallel two series arrangement.

 

Comparing to other battery packs it looks better value for sure, but 4 x 18650 would be at most $US80 retail price so it's quite a bit more than 4 loose cells, which is why people are complaining.  I agree with Dave Hicks though, if others can make a strobe using 2 x 21700 cells it would seem to be a good solution as long as people buy good quality protected cells.

[fruehaufsteher2]

Coming back to the price: I bought 16 Eneloop pro via ebay + Nitecore C4 for less than 100.-

But I have to admit that I already own 2 Boosters that usually come at additional 200.- each.

 

So if i bought new I might have gone for the battery pack. (900.- vs. 500.- and nearly double the capacity).

[Jerry Diver]

16 hours ago, Dave_Hicks said:

I fail to see a tangible difference. How is one cell safe and two a hazard?

Already explained in the topic about the HF1, a brief recap: more than one battery requires careful monitoring of discharging as the electrical properties of batteries are always dissimilar and would start damaging each other if not controlled, especially lithiums. There is no "dry" strobe manufacturer, except Yongnuo YN560Li (2x 18650), that does such a thing as combining more than one loose lithium battery in their products. It's either Nimh or proprietary battery pack. This "trend" is completely unique to the new brands in underwater strobe market that want to blow up their spec sheet at minimal cost.

Edited July 3 by Jerry Diver

[Walt Stearns]

The Yongnuo YN560Li Lithium Speedlite on camera flash uses two 18650 Rechargeable Li-ion Batteries.

[Jerry Diver]

Thank you, I have corrected my text. 

[Jerry Diver]

16 hours ago, Dave_Hicks said:

Compare to the Backscatter HF-1 which I recently bought and am currently evaluating. It's $900 or $950 if you include a pair of the recommend 21700 Li-Ion batteries.

Backscatter is primarily a sales operation, not a strobe manufacturer. Their products are made in Chinese factories and imported to the USA at low costs. They rarely repair products because it’s cheaper to replace them—a Miniflash costs them around $100, and the new HF strobe about $200 directly from the manufacturer. Their Miniflash had a high failure rate (30-40%), but they kept customers semi-satisfied by sending out new units, which only makes sense given the low purchase prices. This approach appeals to consumers who focus solely on price and specs, ignoring the bigger picture.

 

In contrast, companies like Ikelite and Retra manufacture their products in-house, in the USA and Europe, where labor and environmental laws actually apply. One is a powerhouse in longevity, and the other is a true innovator. To my knowledge, Retra is still the only company with a leakage detector in the battery compartment and firmware updates via mobile phone. Personally, I don't need these features, but for some, they are an absolute must-have.

 

There are many strobe options now, so you can choose according to your budget and needs. However, be aware that shiny low prices usually result from cutting corners in areas that might not be obvious when looking at a spec sheet.
 

[CaolIla]

19 minutes ago, Jerry Diver said:

Backscatter is primarily a sales operation, not a strobe manufacturer. Their products are made in Chinese factories and imported to the USA at low costs. They rarely repair products because it’s cheaper to replace them—a Miniflash costs them around $100, and the new HF strobe about $200 directly from the manufacturer. Their Miniflash had a high failure rate (30-40%), but they kept customers semi-satisfied by sending out new units, which only makes sense given the low purchase prices. This approach appeals to consumers who focus solely on price and specs, ignoring the bigger picture.

 

In contrast, companies like Ikelite and Retra manufacture their products in-house, in the USA and Europe, where labor and environmental laws actually apply. One is a powerhouse in longevity, and the other is a true innovator. To my knowledge, Retra is still the only company with a leakage detector in the battery compartment and firmware updates via mobile phone. Personally, I don't need these features, but for some, they are an absolute must-have.

 

There are many strobe options now, so you can choose according to your budget and needs. However, be aware that shiny low prices usually result from cutting corners in areas that might not be obvious when looking at a spec sheet.
 

 

A copy of a part of the answer I received from Retra.


 

Quote

Thank you for reaching out with your concerns. I appreciate the opportunity to clarify a few important aspects regarding our products and our commitment to quality and ethical production practices.

Firstly, I want to emphasize that all our products are proudly made in Europe. We have chosen to base our manufacturing operations here for several key reasons, which I believe are crucial for you to understand and appreciate:

Ethical Labor Practices
Unlike some manufacturing hubs where cheap labor is exploited, our European production facilities adhere to stringent labor laws and regulations. These laws ensure fair wages, reasonable working hours, and safe working conditions for all employees. We are committed to upholding these standards because we believe in treating our workers with the respect and dignity they deserve. This ethical approach not only supports our employees but also fosters a positive and motivated workforce, which is reflected in the quality of the products we produce.

Highest Quality Standards
Manufacturing in Europe allows us to maintain the highest quality standards. Our production processes are regularly inspected and certified to meet international quality assurance benchmarks. We use top-grade materials and the latest manufacturing technologies to ensure that every product meets our rigorous standards. This commitment to quality means that you receive a product that is reliable, durable, and performs to the highest expectations.

Environmental Responsibility
Another significant advantage of manufacturing in Europe is the adherence to strict environmental regulations. We are committed to minimizing our environmental footprint and ensuring sustainable production practices. Our facilities employ eco-friendly methods and technologies to reduce waste, conserve energy, and minimize emissions. By choosing our products, you are supporting a company that prioritizes the health of our planet.

Innovation and Design Excellence
European manufacturing is synonymous with innovation and design excellence. Our products benefit from the rich tradition of craftsmanship and cutting-edge design that Europe is renowned for. We produce everything in-house to create products that are not only functional but also aesthetically pleasing. This focus on innovation ensures that our products stand out in the market for their superior design and performance.

Customer Satisfaction
Ultimately, our goal is to provide you with a product that exceeds your expectations. By manufacturing in Europe, we can closely monitor every step of the production process, ensuring that each product is meticulously crafted to meet our high standards. This attention to detail translates into greater customer satisfaction, as we can confidently stand behind the quality and integrity of our products.

Thank you for taking the time to understand our manufacturing philosophy. We are confident that our products will continue to meet and exceed your expectations.

It's Ok, but for me the price is to high I'm really not sure that if one of my Pro X failed I buy a new Retra...  

[Dave_Hicks]

1 hour ago, Jerry Diver said:

Already explained in the topic about the HF1, a brief recap: more than one battery requires careful monitoring of discharging as the electrical properties of batteries are always dissimilar and would start damaging each other if not controlled, especially lithiums. There is no "dry" strobe manufacturer, except Yongnuo YN560Li (2x 18650), that does such a thing as combining more than one loose lithium battery in their products. It's either Nimh or proprietary battery pack. This "trend" is completely unique to the new brands in underwater strobe market that want to blow up their spec sheet at minimal cost.

Interesting observation and the controlled discharge rates. Where can I learn more about this issue? 

 

Regardless, it seems it could be easily resolved by pairing the two cells used in the strobe with a bit of colored tape so you don't mismatch them. Thoughts? 

 

As for contract manufacturing, this is the way much of the world works. It is not inherently bad if the company involved has done a good job in specification and testing of their design.

 

The Backscatter example with MF-1 is a good one actually. I bought an MF-1 in 2020 and used the hell out of it. I had it fail at least three or four times, an BS always took care of it. I have had the MF-2 for over a year now and it has been flawless. They iterate the design and made significant improvements in function and reliability.

 

This is what gives me hope for the HF-2 and the confidence to buy a pair. 

[Jerry Diver]

10 minutes ago, Dave_Hicks said:

Interesting observation and the controlled discharge rates. Where can I learn more about this issue? 

https://www.sciencedirect.com/science/article/abs/pii/S0378775313019447

[Jerry Diver]

15 minutes ago, Dave_Hicks said:

Regardless, it seems it could be easily resolved by pairing the two cells used in the strobe with a bit of colored tape so you don't mismatch them. Thoughts? 

It's about measuring how each individual battery performs and then combining them. Constantly using the same pair of batteries together could actually be worse.

[Dave_Hicks]

1 hour ago, Jerry Diver said:

https://www.sciencedirect.com/science/article/abs/pii/S0378775313019447

 

TLDR; I think you are making too much of this Single Cell vs Battery Pack issue.

 

Okay, I read this and a bunch of other articles and papers on this topic. This ScienceDirect article is about battery lifespan vs matching of internal resistance. I am not overly concerned about potentially maybe reducing the lifespan of a $25 battery from 500 cycles to 300 cycles. (40% reduction in lifespan per the article) It would take several years for even the most active shooter to run though 300 recharge cycles.

 

Secondly, the specified battery (and most similar batteries) includes protection circuits, pressure release, and other safety features that mitigate much of the potential for things to go sideways. 

 

Reading up a little bit on the properties of battery packs and cell matching, the best practice is that individual cells of the same age and model number may be combined under a single protection circuit. In other words, pack builders are reliant of the quality control of the batch vs individual cell characteristics. 

 

 

Edited July 3 by Dave_Hicks
clarity

[Dave_Hicks]

1 hour ago, Jerry Diver said:

It's about measuring how each individual battery performs and then combining them. Constantly using the same pair of batteries together could actually be worse.

 

I don't see the logic of this. My reading indicates that a matched pair of cells is a good fit. At worst, combining mismatched and protected cells may reduce charge cycle lifespan.

 

I'm no expert on the topic, so fill in the details if I am wrong. I'm willing to be educated!

Edited July 3 by Dave_Hicks

[Davide DB]

The topic is interesting and complicated. I agree more with Dave.

IMO big problems happen during charging. The battery packs have a circuit (Battery Management System) that precisely equalizes the differences between individual cells and also has a cut-off circuit that prevents the batteries from dropping below a certain threshold during discharge.

I don't see any problems when using scattered batteries because after use they will be charged individually.

Having a single pack is more a matter of convenience than anything else, and in any case we are not talking about huge battery packs like those in video lamps.

 

 

[Jerry Diver]

4 hours ago, Dave_Hicks said:

potentially maybe reducing the lifespan of a $25 battery from 500 cycles to 300 cycles.

Both batteries need to be replaced so it's $50 and the lifespan in underwater strobe usage is already much less, probably around 150-200 cycles until we reach 60-70% battery health, because underwater strobe battery usage is the exact opposite of ideal battery usage with sharp spikes in battery drain for fast recycle time. Therefore an additional 40% decrease in battery life is a substantial problem and as a result a well tuned battery pack will eventually cost less.

 

The best I can explain is by comparing it to an engine with 2 or more cylinders (battery cells). If one cylinder works perfectly until 4.000 rpm and the others are good to 6.000 rpm we should limit the rpm to 4.000 rpm. However we can't know this unless we measure all cylinders for wear (internal resistance). If we are constantly running the engine at 5.000 rpm the weaker cylinder will get used more and the stronger cylinders too because they will need to work harder to push the weaker cylinder which is producing much more friction and heat. Eventually all cylinders will add friction and simply stop working, turning over, which is the best case. The worst case is the engine has a failure at high rpm (reverse polarity within the battery). Internal protection circuits help reduce this to an extent but if there is a high enough difference the stronger batteries will damage the protection circuit of the weaker battery and itself.

 

Again, the reputable topside strobe brands never combine two or more loose Li-Ion cells (especially not the powerful 21700) and imagine the pressure they have in a much larger market, the ones who would do it would immediately gain an advantage over their competitors. So why don't they do it? Answer is: it presents too big of a risk for them to open their battery compartment to accept large loose Li-Ion batteries and even if the manual says you can only use such and such batteries you have invited users to insert anything they want and the product can't effectively prevent the damage.

 

6 hours ago, Dave_Hicks said:

I had it fail at least three or four times, an BS always took care of it.

Yikes, I guess the 30-40% failure rate of the backscatter miniflash was even higher.

[Dave_Hicks]

20 minutes ago, Jerry Diver said:

Both batteries need to be replaced so it's $50 and the lifespan in underwater strobe usage is already much less, probably around 150-200 cycles until we reach 60-70% battery health, because underwater strobe battery usage is the exact opposite of ideal battery usage with sharp spikes in battery drain for fast recycle time. Therefore an additional 40% decrease in battery life is a substantial problem and as a result a well tuned battery pack will eventually cost less.

 

The best I can explain is by comparing it to an engine with 2 or more cylinders (battery cells). If one cylinder works perfectly until 4.000 rpm and the others are good to 6.000 rpm we should limit the rpm to 4.000 rpm. However we can't know this unless we measure all cylinders for wear (internal resistance). If we are constantly running the engine at 5.000 rpm the weaker cylinder will get used more and the stronger cylinders too because they will need to work harder to push the weaker cylinder which is producing much more friction and heat. Eventually all cylinders will add friction and simply stop working, turning over, which is the best case. The worst case is the engine has a failure at high rpm (reverse polarity within the battery). Internal protection circuits help reduce this to an extent but if there is a high enough difference the stronger batteries will damage the protection circuit of the weaker battery and itself.

 

Again, the reputable topside strobe brands never combine two or more loose Li-Ion cells (especially not the powerful 21700) and imagine the pressure they have in a much larger market, the ones who would do it would immediately gain an advantage over their competitors. So why don't they do it? Answer is: it presents too big of a risk for them to open their battery compartment to accept large loose Li-Ion batteries and even if the manual says you can only use such and such batteries you have invited users to insert anything they want and the product can't effectively prevent the damage.

 

Yikes, I guess the 30-40% failure rate of the backscatter miniflash was even higher.

 

You are beating a dead horse and repeating yourself.

 

This is not a big deal. I don't care what "topside strobe" makers do. In the photography market there are upsells and revenue generating proprietary battery packs that they can sell for 10 times markup or more. So of course they sell them that way. It is refreshing to see a manufacturer skip out on this fantastic opportunity to squeeze their customers. 

 

Back when I used Ikelite strobes their NiMH battery packs would fade and die after some years of use. Rather than buy a new one for $250 I would just buy $15 of Sub-C batteries at BatteryJunction and rebuild the pack myself. I even had some rebuilt at a Batteries+Bulbs retail store for a mere $25 in labor. 

 

And yes, the MF-1 was problematic, but it was a wildly innovative and very well received product. The MF-2 fixed all the reliability issues and made the initial implementation and features even better. I hope I can say the same of the HF-1 strobes after some more time in market and personal experience.

[insomniac]

Since Backscatter's customer service was brought up on this topic as well; I too would like to contribute my two cents / experiences. I also owned/own an MF-1 and backscatter replaced the unit once for me with no hassle (even shipped two day air for it to arrive prior to my trip). Unfortunately, I had another problem with it which was out of warranty and they asked me to send it in regardless. They determined it could be repaired for a fee of $134; I rejected this and decided to buy a MF-2 instead (they offered a 5% discount on that purchase). So overall not a great but an overall satisfactory experience (especially as it was made all made in China so wasn't a huge investment or loss). 

 

Fast forward to my Retra Pro Max buying experience. Fully kitted out it cost me over 4k; but I figured "buy once, cry once." This was far from the case. I had a horrible time trying to use the strobe in Lembeh; I had major issues with flash sync and even though I had two Turtle TTL converters, I had trouble finding one to reliably work (even after contacting both supports and trying various firmware settings). And then to add insult to injury I was the first to discover a firmware bug when using the 8AA battery backpack; and I fried my focus lights early on in the trip (not a huge deal; but I was looking forward to that helping on some shots).

 

I also despise some of the "UX" decisions they made with these strobes. You can't just "turn them on" you have to first go to the "battery / test" function and wait for many seconds to get a result and then you can finish turning them on. That is insanely annoying and stupid to me. I gave them this feedback and they told me, "it is normal for the strobe to be turned on first in the Batt/Test mode. This mode allows the flash to perform essential system checks, ensuring there is no water inside and verifying that the correct batteries are inserted. Please turn the switch to Batt/Test for a few seconds until the Retra logo appears, and then you can switch to the mode you wish to select."

 

Also, if you forget to turn the strobes off after the dive (even if not using them) they will relatively quickly drain the battery down to 0%. So there were a few night dives where I had 0% battery left, and had to quickly come up with and replace 16AA batteries...

 

After my trip was over I sent in the strobes overseas for warranty service and it was completed relatively quickly. As an aside; on my trip to Lembeh I also lost a $65 diffusor on the trip (user error); and I asked them to replace it for free (for all the hassle I had and the $$$ I spent). They refused to do that; but did offer a one time 15% discount on the overpriced $65 diffusor. I really like they lock in place firmly; so firmly that I didn't put a backup tether on them; but I must have forgot to "lock" them one dive and lost them (unlike the Z330's diffusors which have to be tethered as they fall off almost every dive). Anyways, I quickly discovered they were not going to budge and offer me a free replacement as a good will gesture for all the troubles I had after spending over 4k for their products.

 

All this to say. Nothing is perfect. Cheap and expensive stuff underwater often fails or is lost / stolen. It sucks (have backups if possible). There's no such thing as buy once / cry once in scuba. There's always buying and crying regardless of what option you end up with. As much as I hated to do it; I ordered these expensive add on battery packs. It seems like less of an inconvenience than selling my whole setup at this time; at least the strobes will be neutral or slightly positive. Hopefully the giant battery packs sticking out the end doesn't bother me too much. It's funny that they advertise how much lower profile the 8AA batteries fit in the Pro Max than the prior models, and then they create this monstrosity. If I could do it all over again; I would have never bought these strobes; but at this point I made my bed and now I am going to lie in it.

 

 

 

 

 

 

Edited July 3 by insomniac

[Walt Stearns]

insomniac you are the 8th person I have heard who has had sync issues with the Turtle TTL converters. I would not be quick on blaming the strobes in that case.

[insomniac]

11 minutes ago, Walt Stearns said:

insomniac you are the 8th person I have heard who has had sync issues with the Turtle TTL converters. I would not be quick on blaming the strobes in that case.

 

Whoops; sorry if I didn't make it clear (I wasn't attempting to blame Retra for that). There's too many variables, and I assumed it was most likely Turtle's issue. I can add to my story, that they sent me a new trigger free of charge after my complaints (I just sadly haven't been underwater to test it yet). If anyone has a Turtle TTL + Sony + Retra combo working well; please let me know. Or if you can recommend a different trigger; that would be appreciated (PS: I don't need or typically use use the TTL feature of a trigger; I shoot manual 99% of the time).

 

 

Edited July 3 by insomniac

[TimG]

7 hours ago, insomniac said:

There's too many variables, and I assumed it was most likely Turtle's issue

 

You make a good point.  I had an issue some time ago with a strobe/trigger combination and blamed all sorts of people: Retra, UWT, the Almighty, Life.....  It turned out that the problem was with the way I'd cut the fibre optic cables (with scissors and not with a razor blade). Retra were extremely helpful - not to mention patient - in calming me down, identifying the issue and explaining the reasons and the fix.  

[CaolIla]

second mailing action for the power vault.

null


Probably not enough pre-orders 

[insomniac]

such a good deal (sarcasm). The recommended HF-1's batteries come in at less than half this per wh ($4.15) and don't lock you into a proprietary battery pack. I'm so annoyed I am giving them more of my money. #regrets

[Jerry Diver]

2 hours ago, CaolIla said:

second mailing action for the power vault.

I've gotten at least three emails from Retra for each of their product launches.

 

12 minutes ago, insomniac said:

and don't lock you into a proprietary battery pack.

Show me another underwater strobe where I can choose either 4xAA, 8xAA or a proprietary battery pack...

 

I feel like we should start a whole different topic where we just complain about high prices for just about anything in underwater photography. I have some ideas for starters.

 

Fiber optic cables that probably cost $10 in material, now available at $95: 

null

And what about those trigger boards that cost $20 in electronics, yours for just $695: 

null

[CaolIla]

7 hours ago, Jerry Diver said:

 

Fiber optic cables that probably cost $10 in material, now available at $95: 

Your are wrong   not $10 but $1  😉

[TimG]

Fibre optic cables: make you own. Easy, cheap, satisfying,….