9 hours ago, Chris Ross said:

I really think the fundamental problem is the response curve of the camera. That's not a fault rather that is how they are designed. The way around I think is to reduce the exposure. Easiest is lowering the ISO if possible, but looks like you at ISO 50 already, so maybe place a grey card on the wall and measure brightness off that or double the strobe's distance from the wall. You might run into problems at the low power end, but within the limitations of equipment you have available seems like this might be the best solution. You would need separate sets of measurements for the high and low powers.

Also as I understand it ISO 50 on the Z8 is extended ISO which is achieved by over exposing the image and pulling the exposure down which tends to blow highlights. Maybe for the Z8 base ISO might be a better option?

Some good ideas there. I might experiment with more range and a gray card.

On 1/28/2026 at 7:34 AM, Adventurer said:

Michi, if I read Dave & Killiii correctly than the Maxi is not what you are looking for and simply unable to deliver at these fps.

The Backscatter HF-1 is able to do it (I own and tested this) but there is brightness variation and quite a few blackout frames every few cycles in burst shooting.

The only strobe which is currently doing what you are looking for and which delivers zero light variations and zero blackout frames at high burst for more than 100 frames is the MARELUX Apollo III 2.0 in MTL Mode - which I also happen to own. I would subscribe to everything Henley Spiers wrote in his review:

DivePhotoGuide

First Impressions of the Marelux Apollo III 2.0 Strobe

Both my Backscatter HF-1 and Apollo deliver warmer light than my friends Seacam and old Retra, with a very simple fix I received from Hydronalin, Germany.

Hi, @Adventurer thx a lot for your personal advice and feedback! I guess for now the Apollo is the best product for me

@Dave_Hicks thx for all the effort so far - I appreciate this! it would be still nice if you can set your Camera to 10/15 frames per second and see what the Maxi does compared to the Backscatter a simillar decent power level! If this is not possible, just Let me know (i can Imagine how time consuming These Tests can be…)!

@Kiliii Yuyan thx for your great Test and all the effort - very interesting

I understand with a passing shark 5 shots per second or so is great but with for example a blenny eating algae from Seagrass and catching that exact Moment of the bite a high burst mode changes Everything…

Edited February 2Feb 2 by Michi

I took a break from shooting strobes at walls and went diving!

The assignment this time was CFWA with a 15mm fisheye lens and the Maxi's with a warming filter and reduction rings. Visibility was a pretty hazy silty 15ft / 5m so reduction rings were a big help.

Nikon Z8 w/8-15mm Fisheye lens, f11@1/30s iso400, Pair of Retra Maxi strobes with 4500k filters

Nikon Z8 w/8-15mm Fisheye lens, f11@1/30s iso400, Pair of Retra Maxi strobes with 4500k filters

Nikon Z8 w/8-15mm Fisheye lens, f11@1/40s iso640, Pair of Retra Maxi strobes with 4500k filters

Dive buddy Nirupam testing out a Nikon ZR / Ikelite setup.

22 hours ago, Dave_Hicks said:

I took a break from shooting strobes at walls and went diving!

😃As much fun as it is to measure and research new stuff, not much point to it unless we go diving!

On 2/2/2026 at 6:46 PM, Dave_Hicks said:

Maxi's with a warming filter and reduction rings. Visibility was a pretty hazy silty 15ft / 5m so reduction rings were a big help.

Thanks for the great images and review. I was wondering if you could elaborate on stacking reduction rings with the warming filter. Are both of these the standard ones from Retra and can you put them in series? I also dive in meh visibility water and so was wondering how to lower the color temp while also reducing backscatter. Thanks!

1 hour ago, ColdDarkDiver said:

Thanks for the great images and review. I was wondering if you could elaborate on stacking reduction rings with the warming filter. Are both of these the standard ones from Retra and can you put them in series? I also dive in meh visibility water and so was wondering how to lower the color temp while also reducing backscatter. Thanks!

I made my own reduction rings that accommodate a diy filter. Message me if you want more details.

I spent a little time today Re-Flashing some wall space with an aim to create more separation between the three strobes at the highest power levels. The tests so far have not shown a lot of gradation, possibly due to the short distance, low ISO, and small aperture.

I repositioned at 150cm from the wall, set ISO to the Z8 base of iso64, and aperture of f16. I only shot the Boost, +2, +1, and Full settings on the three strobes, as applicable. Photoshop luminance Mean and Point measures collected. I calculated a delta of the Mean measurements with the Maxi Boost mode as 100% and other results relative to that.

There is indeed a greater spread between the measured results using this method, supporting the idea that the previous settings were probably losing fidelity and flattening the results.

TLDR;

• Maxi@Boost > HF-1@+2

• Maxi@+4 (aka Full) > HF-1@Full

• HF-1@Full > Atom@Full

Here are the results and visualization:

7 hours ago, Dave_Hicks said:

supporting the idea that the previous settings were probably losing fidelity and flattening the results.

I think this supports also the 5% measurement and test + item variation delta I previously pointed out. Also a fresh from the factory strobe will be brighter than one that already has fired a few hundred shots. So no need in beating a dead horse and over-doing and over-interpreting these land tests.

What would be interesting though is a beam (1-1.5m) wall test submerged in water to see the different dome and reflector designs come into play.

4 hours ago, Adventurer said:

I think this supports also the 5% measurement and test + item variation delta I previously pointed out. Also a fresh from the factory strobe will be brighter than one that already has fired a few hundred shots. So no need in beating a dead horse and over-doing and over-interpreting these land tests.

What would be interesting though is a beam (1-1.5m) wall test submerged in water to see the different dome and reflector designs come into play.

All of the strobes have fired at least 1000 times now, HF-1 tens of thousands at least. I won't be doing any static in water testing.

On 1/29/2026 at 2:55 AM, Chris Ross said:

If I am reading things correctly Killiii's test shows some interesting points.

First he tests at 8 FPS on the Apollo III in MTL at 12 = (max power) and it illuminates every frame and drops one stop in power by frame 8. It stabilises with constant brightness when power is reduced to 9 . The important thing to note that full power in MTL mode is about 1/2 the max output of the strobe. So it is one stop down from max power in regular manual mode.

The Retra Maxi goes close to the this when set to -4 power- it starts brighter and drops to lower than the the output from the Apollo after a few frames. I'm wondering if the test would be more informative if you set the Retra Maxi at a power to achieve the same light level as the Apollo III at the 9 setting? It should give a few more frames at that setting compared to what was achieved in the test.

The test then goes on to compare the Apollo III and Maxi at 6 FPS with a diffuser on the Apollo as it really needs one to get close on light quality. Settings are 12 and -6 respectively and the light output is the same by the light meter reading.

To me it seems any comparison should be at a setting where light output is constant and equal. If you want high speed shooting then only getting the strobe output for the first frame or two kind of defeats the purpose. Whether one strobe is at half power and the other at 1/4 is somewhat irrelevant, to get a true comparison you want the same amount of light falling on your subject.

I ran the test you're describing 2 years ago between the HF-1 and Apollo III (basically, normalized power output after the initial dimming period) to see what the max power each strobe could achieve in a continuous shooting scenario at 3fps, 6fps and 12fps was. Here's the results (also in the shared google spreadsheet that's pinned at the top of this forum). My results were that in actuality the HF-1 puts out more power at each frame rate than the Marelux Apollo 3 despite the latter marketing its MTL feature heavily. (I have no incentive to make this up -- I own the Marelux Apollo 3 and have been trying to sell my 2 units since.. 2 years ago :))

Strobe	GN @ 3fps	GN @ 6fps	GN @ 12fps
Backscatter HF-1	16	11	8.5
Backscatter MF-2	13	2.8	2.8
Supe D-Pro	13	10	8
Marelux Apollo 3	11	7.1	6.3
Ikelite DS230	11	0	0
Inon S-220	10	5.6	5
Sea & Sea YS-D3	9	4.5	4.5
Seacam 160D
Retra Pro Max

6 hours ago, DreiFish said:

Marelux Apollo 3 despite the latter marketing its MTL feature heavily. (I have no incentive to make this up -- I own the Marelux Apollo 3 and have been trying to sell my 2 units since.. 2 years ago :))

Hi Dreifish, I think your Apollo III units where not functioning OK or your test setup was faulty in some way. I cannot confirm the way you trashed that strobe, having now shot this and the HF-1 for two years. I bought the HF-1 because of your disruptive Excel sheet back in the days.

In fact my HF-1 does not deliver the power you claimed at high frame rates and does many blackout frames and light variation.

You may want to reach out to your dealer or Marelux to get your strobes replaced.

2 hours ago, Adventurer said:

Hi Dreifish, I think your Apollo III units where not functioning OK or your test setup was faulty in some way. I cannot confirm the way you trashed that strobe, having now shot this and the HF-1 for two years. I bought the HF-1 because of your disruptive Excel sheet back in the days.

In fact my HF-1 does not deliver the power you claimed at high frame rates and does many blackout frames and light variation.

You may want to reach out to your dealer or Marelux to get your strobes replaced.

Hi @Adventurer , I believe you have Apollo III 2.0 strobes based on your previous posts, the data from @DreiFish mentions Apollo III, not Apollo III 2.0 - is this referring to the same model strobes?

23 hours ago, Adventurer said:

Hi Dreifish, I think your Apollo III units where not functioning OK or your test setup was faulty in some way. I cannot confirm the way you trashed that strobe, having now shot this and the HF-1 for two years. I bought the HF-1 because of your disruptive Excel sheet back in the days.

I found the same thing using the Apollo strobes vs the Backscatter HF1s shooting blackwater back in March. Working in the desirable range of 2-4 frames a second shooting blackwater (you really don't need to shoot faster than that), I found the HF1 always gave me more light than the Apollo. Marelux suggested there might be something wrong with both of their strobes I was using.

Edited 9 hours ago9 hr by Alex_Mustard

Matthew and I recorded this last week about the Maxi. Not much new here - we summarise a lot of what is in this thread. But we do show lots of photos taken with the Maxis and also video of us shooting with the strobes.

4 hours ago, Alex_Mustard said:

I found the same thing using the Apollo strobes vs the Backscatter HF1s shooting blackwater back in March.

@Alex_Mustard Didn't you shoot Apollo S strobes, not Apollo III 2.0 in blackwater ?
From what I understand smaller sized Apollo S are supposed to be much weaker than HF-1.

I just recall you not finding the MTL mode when you had Apollo III 2.0 in the Red Sea with Oceanic Whitetips?
You must have gotten distracted by the lovely bouncing batteries, you were so enchanted about 😏

14 minutes ago, Adventurer said:

@Alex_Mustard Didn't you shoot Apollo S strobes, not Apollo III 2.0 in blackwater ?
From what I understand smaller sized Apollo S are supposed to be much weaker than HF-1.

I just recall you not finding the MTL mode when you had Apollo III 2.0 in the Red Sea with Oceanic Whitetips?
You must have gotten distracted by the lovely bouncing batteries, you were so enchanted about 😏

I shot the Apollo III for both oceanics in the Red Sea and blackwater in Anilao (see below). I shot the Apollo S during the day in Anilao.

4 hours ago, Alex_Mustard said:

I found the same thing using the Apollo strobes vs the Backscatter HF1s shooting blackwater back in March. Working in the desirable range of 2-4 frames a second shooting blackwater (you really don't need to shoot faster than that)

That seems a bit different from what you said in the video. I actually stumbled across it again while trying to find Dr. Alex Mustard’s Marelux Apollo review.

It’s not easy to locate, because the review is kind of “hidden” under a subtle title and isn’t as heavily keyworded or clearly titled as the RETRA strobe episodes on The Underwater Photography Show.

As a regular viewer and big fan of the show, I’d like to suggest something: maybe you could give the Marelux “Apollo S” and “Apollo III (revisited)” strobes their own dedicated episode, so they’re covered as fairly and prominently as the Retras and Krakens—which have been episode headliners, sometimes with less overall content.

Anyway,...
Thanks to ChatGPT I was able to pull out a well formatted and still exact quote from the videos transcript.

on 17th March 2025, Alex_Mustard said into the camera:

[ .. ] One of the things we didn't talk about when I reviewed the Marelux IIIs on here previously was their MTL mode which is their fast shooting mode, and I did try that with the with the Marelux III on a Blackwater Dive one evening. And those evenings those Dives were really good Dives, so I think I shot something ridiculous like 830 photos across two blackwater dives using the highs speed shooting. Mathew Sullivan: "I have your message up, it was 883, or even more" Alex: I was I was yeah. so I set my um A1 on high speed which is I think like up to 20 frames a second or something ridiculous. it wasn't shooting anything like that, I don't know what it was shooting, maybe like each burst was about four or five shots um, but the strobes kept up with that perfectly. Um they do lose quite a lot of power when they put them in that mode. I had them on full power and on exposure terms that seemed about equivalent to the HF 1s on quarter power. And remember the hf1 actually have two settings above full, so that's quite a lot of clicks back on the HF-1 that you're going to. I would also say that actually I wasn't shooting close to 10 frames a second, and I think that although people… I do think shooting short bursts is a valuable thing in Blackwater shooting. I think there's a few factors to remember.

This is actually where you 100% confirm my experience with the Apollo III 2.0 ... The Backscatter HF-1 on quarter power will approx the same at 1/4 power as the Apollo III 2.0 at FULL in MTL - It will hold it's stamina at 12fps .CR3 RAWs for approx 1000 frames. And the Apollo holds its stamina: it can keep up at around 12 fps shooting CR3 RAW bursts for roughly 1,000 frames. In my case, the limiting factor is my camera buffer * — not the Apollo III strobe. With the HF-1 set to 1/4 power and trying the same kind of burst, the strobe quickly starts producing blackout frames or underexposed frames every few shots.

* Well,... if you cross 1000 shots the battery cells in any strobe also become a limiting factor.

When there is talk about power drain, I can confirm that firing above 800 shots will drain strobe batteries... but not light output provided in MTL by the strobe. That is until you cross a critical battery level signaled by the strobe indicator light going yellow or purple.

I would observe that we have two independent people stating the HF-1 out performs the Apollo III strobe and one person reporting that the Apollo III is better compared to their HF-1. Surely it's equally possible that the HF-1s in question(or their batteries) are under performing compared to the Apollo III samples as the only data available is the comparative performance of the strobe samples that are owned. It could also be related to the batteries being used in each model as these seem to critical to achieving this sort of performance. Backscatter in particular are quite vocal about using the right type of battery and it's not unheard of for batteries to lose performance after some use.

24 minutes ago, Chris Ross said:

I would observe that we have two independent people stating the HF-1 out performs the Apollo III strobe and one person reporting that the Apollo III is better compared to their HF-1

No please do not get me wrong.

I am not saying anything is better.

The HF-1 is a tick stronger than my Apollo III 2.0 when put to +2 mode and you do not want to utilize burst shooting.

But when you want high fps strobe burst shooting it seems to me that no other manufacturer has mastered this technology than Marelux. Maybe also the other competing companies did just not aim their design at this particular discipline.

And I just want to say that I have noticed that this particular aspect of the product seems to get downplayed in many reviews or comments during the last 1.5 years. Most reviewers seem to have adapted their testing ground to an fps level or use case that the competitor products still can cope with. The only guy who can not be critiqued for being an Ambassador and having written a fair independent review about the Apollo III is Henley Spiers on DPG. Many others seem downplay the aspect and image opportunity of high fps strobe shooting, even if they found the product to perform that decently during their tests. I own and paid both strobes (HF-1 and Apollo III) and think their are both great tools where they go stellar in different disciplines.

My impression is that for some reason I do not understand there seems to be some kind of Marelux or Apollo bashing going on or beeing popular to say - and just few people credit this brand of having introduced a new piece of tech that others still need to catch up to.

The whole thing with the high fps downplay reminds me of my old Hugyfot housing, when that brand introduced vacuum systems on their housings as the only manufacturer around. Everybody else was making fun about them for this and said „our housings also seal without this“. Look now 20 years later and vacuum valves and pumps on housings are a standard. Especially on brands that were shouting Extra loud against them in the period were they did not sell this technology.

Hmmm, not sure I've seen anything I'd call strobe brand bashing. Well not since the old Sea & Sea issue anyway.

Seems to me these are all perfectly good strobes we're talking about. We all have brand preferences based on personal experience, a specific feature or just their good looks. Producing truly accurate comparisons is incredibly difficult given the vagaries of environment, set up, batteries etc. Some amazing work has been posted here by folks who have put hours of work and thought into testing - for which, massive thanks.

After that, yeah, I'm sure one can be tweaked slightly differently from another. But aren't we getting a bit beyond the point? Take your pictures and enjoy them. No matter how perfect the bit of gear might be, something underwater is going to lead to some sort of degradation in perfomance.