Backscatter.com Strobe Comparison

Guide numbers specify the brightness of the strobe, that's all. Beam pattern is obviously also important. A wider strobe is not brighter when the guide number says it's not, and a higher guide number doesn't mean that a strobe is narrow or hot in the center. A guide number specifies one thing only and it specifies it well. Measuring "in the center of the beam" is appropriate for determining guide numbers and it does not disadvantage any manufacturer to do so.

I'm sure the tests were performed properly but I'd suspect they were done in air. A strobe's beam pattern can only be accurately tested in water and, because of this, a strobe with a smooth beam pattern could give an inaccurate reading in air. The water/strobe interface will bend the strobe light differently than it does in air and that may effect readings depending on the design of the strobe.

One thing that the tests do show is that the Z-240 is not heavy in water as some claim that it is. In salt water, a Z-240 is heavy enough to sink when let go but it is almost impossible to feel it in your hand. I'd say an ounce negative at worst. What makes the Inon heavier is the ball adapter and clamp. When a Sea & Sea adapter and YS arm is used, they are lighter.

I'm glad the Inon isn't positive. A strobe that floats is useless as a drop strobe. The biggest problem with strobe bouyancy, at least with Inons, is the heavy armset.

Guide numbers specify the brightness of the strobe, that's all.

This is why I still shoot with SS200's for wide angle. The GN difference from the Z240's might be minimal, but it still feels, and looks in the resulting images, that the SS200s hold much more brightness at the edges. I suspect the Z240's fall-off significantly from the center to the edge of their claimed 100 degree AOC. I love the Z240's but they do place an earlier limit on wide angle options than do the SS200's. I shoot Z240 for macro and SS200 for WA.

As far as weight goes, the only thing that matters to me is baggage weight. I find that much more of an impact than I do the bouyancy level underwater. I wish I could leave the SS200's home, for this reason, but I still haven't found a lightweight (in air) strobe that does the same job underwater.

Yes, no doubt beam pattern is an important consideration and guide number says nothing about it. People imply, though, that high guide numbers with certain strobes are somehow evidence that they have poor beam patterns when compared to other strobes. It seems that nothing is more rejected than a strobe test. Yes, it is possible that some strobes simply outperform others and, yes, guide numbers are an effective, important, objective measurement given they are compared properly.

What makes you suspect that a Z240's light falloff is substantially more or different for its claimed angle of coverage than other strobes? The digital diver strobe test contained pictures of an Inon strobe pattern compared to a DS-125 and there was no clear evidence that its beam pattern was worse or even usably different. That test may have flaws but it's still the best effort made so far and the new Backscatter test doesn't offer different results. Frankly, I think a carpeted trunk is more revealing of beam pattern irregularities than an underwater image will be.

There are active threads here discussing specifically the use of Inon strobes with 180 degree fisheye lenses and images are posted. I did some testing recently with that configuration as well and was diving with a photo pro that was using 180 FE with twin Inons. If he wasn't getting coverage then he probably wouldn't be using them.

Considering the dramatic difference in travel weight between 200's and Z240's, you can easily consider diving with 3 or even 4 Z240's for less weight. I dove with quad Inons on my last trip and it was easy and fun. The advantage of 3 or 4 smaller strobes is more flexibility should strobe failures occur. If you are travelling with 3 Z240s for macro and 3 200s for wide then you are paying a heavy price for that flexibility.

One thing I find interesting is how much value people place on a circular strobe tube and a perfectly round beam pattern, ignoring the fact that they use multiple strobes offset from the lens and their resultant images are rectangular. The subjects are rarely anywhere near round anyway.

What makes you suspect that a Z240's light falloff is substantially more or different for its claimed angle of coverage than other strobes?

The digital diver strobe test contained pictures of an Inon strobe pattern compared to a DS-125 and there was no clear evidence that its beam pattern was worse or even usably different. That test may have flaws but it's still the best effort made so far and the new Backscatter test doesn't offer different results. Frankly, I think a carpeted trunk is more revealing of beam pattern irregularities than an underwater image will be.

I did some testing recently with that configuration as well and was diving with a photo pro that was using 180 FE with twin Inons. If he wasn't getting coverage then he probably wouldn't be using them.

Considering the dramatic difference in travel weight between 200's and Z240's, you can easily consider diving with 3 or even 4 Z240's for less weight.

My comment was in regard to the edge performance between the 200 and Z240. The Z240 definately suffers more falloff, respective to it's center brightness, than the SS200's do.

I don't think that the 200 being wider than the Z240 should come as a surprise considering its 3x weight , 1/2 cycles per charge, larger battery, its lack of superior brightness and identical recycle times. It *has* to do something better, right? Does anyone dispute that the 200 is a wider strobe? Backscatter did not test beam pattern. Ultimately, you have to set correct exposure based on ambient conditions and strobe power. Beam pattern is useless for that; guide number is what you need to know.

I base my judgements on real world underwater performance. But I realize test patterns are fun to use as a talking point.

You prefer handwaving to measuring? What test charts are you referring to? Aren't the ones without objective data the ones with the talking points?

I dislike responding to this kind of rationale because it ends up sounding rude, but, I seldom default to what pros find acceptable or unacceptable. To go back to my original comment: What is coverage? Where does coverage end? Is it 1 f-stop down from center, is it 2...or 3. At what point does one decide that the edge of coverage is within the image or outside the image? Is your pro's coverage the same as your coverage or my coverage?

Yes, we know there's no standard for specifying beam pattern. You haven't defined one either nor have you quantified the differences you say exist. It's generally accepted that the Ike 200 is very wide. Is the DS-125 wider than the Z240? It's rated by Ike to have the same beam width as the DS-200.

He was not "my pro" BTW but I suspect his standards for lighting quality are every bit as good as yours or mine and I doubt he'd be using them if they weren't doing the job. If he were taking the same shot as you or me, his coverage requirements would likely be the same. It's not that mysterious a process.

No I can't I like handheld single strobe shooting from time to time, so SS200 and backup is necessary.

I'm willing to consider any technique that might be better than what I've done before. I also trust objective testing because it's far more reliable than gut feel. I'm curious to know why you believe a superwide strobe is required when using a single handheld. What look are you hoping to get that requres superwide coverage in a single, handheld strobe that can't be achieved by mounting that strobe on an arm?

One thing is certain is that, every time strobes are discussed, someone will inevitably claim that Ike strobes are better and Inons are unsuitable for wide angle use. I don't have a problem with the Ike 200, it's the only Ike strobe I'd consider using, but I do have a problem with the insinuations that Inon strobes are somehow cheating to get their superior guide numbers. It has nothing to do with measuring down the middle.

The best solution is to provide both Guide Number and the Watt/Sec output of the strobe.

Alex

Watt-sec is a measure of the electrical input. We're interested in the light output. The efficiency in converting electrical energy to light can vary by more than a factor of 2 for incandescent sources and is very sensitive to filament temperature which also determines the color of the light output. Lower temperature, redder sources are much less efficient. See for example:

http://en.wikipedia.org/wiki/Luminous_efficacy

I think there is an actual standard for measuring beam pattern - less than one stop deviation from center. I haven't checked to see if it's like an ISO standard or what but I think it's accepted industry wide for flashguns (topside too).

Cheers

James

I haven't seen a formal standard, but measuring the angle at which the light falls off by one stop would go a long ways to characterizing the strobes.

I don't think that the 200 being wider than the Z240 should come as a surprise considering its 3x weight , 1/2 cycles per charge, larger battery, its lack of superior brightness and identical recycle times.

You prefer handwaving to measuring?

Yes, we know there's no standard for specifying beam pattern.

He was not "my pro"

One thing is certain is that, every time strobes are discussed, someone will inevitably claim that Ike strobes are better and Inons are unsuitable for wide angle use. I don't have a problem with the Ike 200, it's the only Ike strobe I'd consider using, but I do have a problem with the insinuations that Inon strobes are somehow cheating to get their superior guide numbers. It has nothing to do with measuring down the middle.

Still, Z240s have a limited application to wide angle shooting compared to SS/DS200s. And they may, considering what some of the people I have respect for are shooting, have a similar disadvantage compared to DS125s, which is a result the Backscatter tests wouldn't indicate.

Victor, you've made it clear that you think the Ike 200s are far better wide angle strobes than the Z240s. That was the whole purpose of your post to begin with. I suppose that, for people who only value beam angles in a single strobe, the 200 looks pretty good. There are better strobes than the Ike 200 for that, though. Try a Harty 625.

As I said before, it should surprise no one that the Ike 200 is a better wide angle strobe than the Z240. It's a large, dedicated WA strobe, after all, and the Inon strobe is general purpose. Why you think that is irrelevant to the topic I don't understand.

The DS125 is a far more interesting match for the Z240 because both can be considered "general purpose". I don't have near the confidence you do that the DS125 will demonstrate clear superiority for wide angle shots. It may demonstrate wider coverage but there are other compelling arguments in favor of the Z240 and, unlike you, I haven't closed my mind to alternate techniques that could leverage the unique advantages of certain equipment. Pound for pound, Z240s can be dived 2-for-1 compared to DS125s and there's no way a DS125 could match the brightness OR coverage in a 2-to-1 comparison.

The most interesting argument I've heard in favor of a DS125 over a Z240 came from a divemaster on my last liveaboard. He felt that managing the custom batteries of the 125 would be simpler than keeping track of a large number of AA rechargables and felt like the simplicity DS125s afforded him was more important than the travel weight penalty. I don't know if, in practice, that will prove to be true but it is an interesting perspective. I've never had issue managing AA batteries but I don't spend months at a time on a liveaboard with his amount of gear either.

I don't appreciate your continued association between the photo pro I referred to and me. He was not "my pro" nor my "dive buddy", and it seems that you feel it somehow discredits him to refer to him in that manner. I used the term pro as a shortcut meaning "enough experience to know the difference". I could express the same degree of skepticism for the people you have "respect for" as you have for mine but I don't see the point of such a ridiculous pissing contest. Those who choose to attack the credibility of people making the arguments, as you have done, generally do so because they cannot engage objectively in the discussion. Frankly, I find that pros are frequently not experts on equipment. They are, after all, after images rather than gear. Pros will not tolerate gear that doesn't work, though.

Do you doubt that an experienced shooter might consider Inon strobes in combination with fisheye? What evidence do you have that they aren't suitable? I shot 180 fisheye with two (and four) Z240s and specifically practiced close focus coverage. No doubt coverage could be easier to achieve with a dedicated WA strobe but I could get subjects to fill the frame and get them lit. My biggest struggle was with shadows and a wider beam isn't going to help with that as much as more strobes or more distance will.

180 fisheye is only one kind of shooting and this is only one aspect as well. If all one does is fisheye with a single, handheld strobe then I'd agree that one Z240 isn't a good choice. Enjoy that creative freedom.

It seems that every discussion of strobe tests ultimately results in the insinuation that strobes that do well, i.e. Inon, have poor coverage when coverage is not covered in the test at all. Test results say nothing of coverage and are not proof that coverage is good or poor in any strobe. As Herb pointed out, there can be substantial differences in the conversion efficiently of electricity to light. There can also be efficiency losses in the power supplies. These differences alone can explain the variation in brightness between strobe models. While it is certain there are coverage differences, they aren't necessary to explain the differences in the Backscatter results.

Victor, you've made it clear that you think the Ike 200s are far better wide angle strobes than the Z240s.

My Inons are fine for certain and more limited wide angle use and my 200's are fine for certain and less limited wide angle use. In broad terms I consider my Inons as macro strobes and Ike's as wide angle, but there is a lot of photographic territory between those two and I'll use either set, or combination of strobes, as I believe or know they will work.

I don't want to belabor a discussion that is fast falling into the realm of emotional discourse (not to mention that I have't the time to argue with all your unrelated questions, accusations and insults). Though I will end my participation by saying that for my imaging the Z240s and SS200's fit very nicely together as a combination of tools that give me the control, reach, reliability, color temps, power settings, size options as well as light that I find pleasing. Four Inons would not do the same because of the wide angle and reach limitations and 4 Ikes would not because I'd be uncomfortable having only Ike's in my photo case due of reliability concerns.

That isn't to condemn what you use or how you use them, it's simply a matter of what works for me. And my comments are generated from what I have learned about each type of strobe after shooting them back to back, and at times side by side, since I bought my Inons early last year. Conceivably, that is genesis for the disagreement between your and my understanding of the differences, similarities and performance between these strobes.

Ike contradicts themselves with regards to strobe specifications and I think you give them too much credit for their short paragraph regarding angles of coverage. If we were to believe Ike, the DS125 and DS200 would be virtually identical in performance. Look here if you don't believe me.

Guide number AND beam pattern are important. Guide numbers are easy to measure while beam patterns are not. That's why we have what we have. Simple as that.

I believe I could "outreach" your 200 with Z240s if you let me shoot 2-for-1 or even 3-for-1 that the weight difference would allow. There is a legitimate reason in preferring to use one or two strobes rather than more, but it's a useful exercise to consider what more than two, smaller, general purpose strobes could do in comparison to shooting dedicated larger ones, especially if you value travel weight as you said originally you do. Perhaps you should do some objective tests before claiming that four Z240s could not do what two 200s could due to wide angle and reach limitations. Perhaps you could suggest a scene where four Z240s are at a disadvantage.

I don't know that we have any disagreement on the performance of these two strobes even if we don't agree on their suitability to certain tasks. I do object to your claims that certain strobes use misleading AOC terms without evidence, I object to you extending your Ike 200 observations to the 125, and I object to you trivializing the example I gave because you feel photo pros aren't what they used to be. I'm as willing as you are to dismiss a technique a pro uses (especially when that pro uses my macro port as an ashtray, as happened on another trip) but one thing pros generally share is a commitment to logging underwater hours and getting profitable images. I don't think any pro would waste their time using a setup they knew wouldn't do the job.

I'm glad we've established that Inon's are suitable for at least some wide angle use. I think there's no doubt that DS200s are better for wide angle strobe-for-strobe. If you prefer not to consider more than two strobes for wide, that's your choice. It's an option that most don't consider even though it's possible (if not practical).

I could make a sound technical argument for why I believe that a Z240 produces 60-75% of the total amount of light that a DS200 does. While that is reasoned conjecture rather than proof, is you accept that it is true then it could be easily seen that 3 or 4 Z240s would match the total light output of a pair of DS200s. What would then determine performance would simply be whether we are able to get that light where we want.

Interesting discussion - I'm enjoying the back and forth - as long as you two can drop the negative personal remarks.

I think all three of us have used the 3 strobes in question (Inon's, DS125's and DS200's). Craig: what I don't see is any compelling reason to sport 4 smaller strobes in place of 2x DS200's. Now that you've done a dive trip w/ a 4-strobe setup, can you shed some light on this? Just thinking out loud, it seems like the negatives are that the setup would be unwieldy, negatively (or at least neutrally) buoyant, vs the nice buoyancy of the 200's, and that the light temp would be significantly higher than I'd like. But I can see that there would be some pluses, and I'd love to hear about it.

Cheers

James

My biggest complaint with the 4 strobe setup was not in actual use but rather in converting back and forth between macro and wide angle. It takes more time but really isn't a big deal.

You might think that four strobes takes more time to adjust because of all the fussy knobs, but I slaved two strobes off the other two using fiber. I only adjusted two strobes like most everyone else, and when I wanted individual adjustment I had it. Another big advantage of the fiber approach was that I never had to change a sync cord.

If you go by the backscatter tests, four Z240s offer the same bouyancy as two DS125s and I don't hear any complaints about that. On the contrary, more strobes means the opportunity for more bouyant strobe arms and bouyancy was the least of my worries. I ran 2 ULCS 10" fatties and 2 Inon strobe arm floats so I had the benefit of 20-25 ounces of lift to help offset my rig. My strobe setup was positive! BTW, I used YS adapters for my Inons rather than ball mounts. The overall combination is lighter that way.

Regarding color temps, the consensus is that lower is better for wide angle and the Inons are somewhat high. That *can* be corrected by an 81C on the Inon (at the cost of a 1/3 stop or so) but since I use complementary filters the strobe temps are not a disadvantage for me. I get bluer water a different way, and Inon strobes are quite easy to filter.

When shooting with four strobes, you have to decide how you will array them. I mostly did so in a line although I'm of the opinion now that a square might be better. I did try using the square configuration some but macro took over later in the trip. When shooting reef scenics with a fisheye, you get so close that shadows start to be difficult. Extra strobes allows for great flexibility in placement but at a cost of a great deal of time to set up. I think it's better to back off a bit and shoot a bit less wide sometimes. The 10-17 is great for offering that option.

On the trip we had numerous opportunities to shoot schooling jacks and most of us were using 180 fisheyes to do so. It's a great advantage in that situation, since the sunball is always in your shot, to have as much firepower as you can get and four Inons is more than two DS125s (that most were shooting) or two DS200s (that one was shooting). For me, anything shot less than f/16 was a wasted shot and I never shot anything less than 4x full power. I didn't get any blown out jacks either.

As far as advantages of more Inons over two DS200s, that's pretty easy. First, Inons are far more suitable for macro use so you don't need to travel with different strobes. Second, 3 or 4 Inons means you inherently have a backup strobe for macro and, in my case, have a third on your BC for flexible macro lighting options. Inons use small, light, cheap AAs so travel is far better than with custom chargers and packs. Finally, Inons enable you to completely rid yourself of sync cords, thus improving reliability, bouyancy, and travel weight.

As for the future, I believe I may try a 3 Inon configuration in a triangle rather than sticking with 4. Doing so is more bouyant (because of the strobe arm details), easier to configure between dives, and simpler to shoot underwater. I think it will be wide and powerful enough for most situations.

As some who know me better are aware, a couple of goals I had for my last trip were to convince myself of the 10-17 and the suitability of 3-4 Inons over the DS200s. With travel weight at even more a premium now, a dedicated wide angle strobe must really prove itself worthy of the weight premium and I just didn't see the Inon solution as lacking in performance. As for the 10-17, I was really impressed. Alex is right, full framers are really at a disadvantage not having the 10-17. It still doesn't discourage me from FF ;-)

With three Z240s, I get good macro, a drop light for backlighting, functional wide angle, and a backup should one strobe fail. I get that for a travel weight of 7-8 pounds (including two sets of batteries and two chargers) PLUS I get synergy with my modeling light since it also uses AA batteries. With two DS200s, the strobes alone are 8 pounds not including extra batteries or chargers and you get no redundant strobe nor compact solution for macro. I think that advantage is clear. Nevertheless, I think the DS200 and YS250 are appealing strobes just as I loved my Hartenburger 625s. I just didn't like the travel burden!