Hammer head-to-head

Lockdown boredom led me to wondering which, if any, of my old 'spud-masher' or hammerhead flashguns to hold on to. The collection includes old Metzes, Sunpaks and oddball Osram/Wotan models.

 

I set up a small 'still life' and placed the tripod 5.6 metres away from it, as measured by an ultrasonic gizmo.

 

Methodology:

In each case I determined the optimum aperture by centring the histogram of the included Kodak grey card. As near as possible. If the 1/3rd stop steps didn't hit centre exactly, I used the f-stop that was slightly higher, rather than lower.

 

I left the camera WB on daylight, since that would better show how suitable the flash was for synchro-sun use.

 

In each case the flash was fired at full 'power', with at least 30 seconds allowed between firings for the capacitor to recharge.

 

All weights quoted include rechargeable battery or AA cells.

 

The text on each picture is a neutral 18% grey in sRGB space.

 

First up, the 2.4Kg Metz 60CT-4.

As you can see from the aperture needed, the Guide Number isn't 60 at all. More like 50. Trigger voltage is a safe 4.6V.

 

Next, a Metz 45CT-4, weighing a shade over 1Kg.

This time the 45 GN is pretty much spot on.

 

Now for the 'lesser' brands. Starting with a Sunpak 'Autozoom' 3600. Weighing in at a fairly hefty 1.3 Kg with needed hotshoe adapter.

Note that the ISO used is 200 this time, meaning this flash has a true GN of 36 as implied by the model number. Trigger voltage without dedicated hotshoe adapter is a naughty open-circuit 350 volts! The adapter drops that to a tolerable 11.2V.

 

Next up is a Sunpak 455 - weight 1040 grams.

It has a slightly higher GN of close to 40 and a much safer trigger voltage of 6.6V.

 

I also tested a Sunpak 555, but the results and stats are so similar that it only duplicates the above.

 

Now for the Maverick in the pack. A Wotan S440, with a unique design that swivels only the reflector for bounce. It has a built in diffuser that also swivels into place and boasts a built-in slave trigger. lt weighs only 800g. The exact same flash was sold under the Osram brand name (also tested - with identical results)

Again the GN is 40 and not the 44 implied by its model number.

Trigger voltage with SCA300 adapter is 10V.

 

To round things out I threw in a few hostshoe mounted speedlights.

 

A Nikon SB-28 zoomed to 35mm coverage angle. Weight 426g.

Guide Number 36. Trigger voltage 4.4V.

 

An SB-800 at 483g including 5th AA cell 'power bulge' gave visually identical results. Trigger voltage measured a bit lower at 3.6V.

 

A 'cheap' Yong Nuo 560-III weighed 475g and gave this result.

GN = 36. Trigger voltage 4.2V. The YN560 also offers built-in slave triggering.

 

Just for fun, I doubled up the hotshoe mounted YN560 with the Wotan S440 in slave mode and got this result.

We're back down to 100 ISO again now, with a combined GN of 50 - same as the Metz 60CT-4, but at about half the weight!

That includes the metal bracket supplied with the S440.

 

The double shadow with both flashes direct is a bit ugly, but the bounced result is quite nice. With the added advantage that the aim of the separate heads can be varied to give a better spread of light.

 

Conclusions: The Sunpak AZ3600 gives probably the worst 'power-to-weight' ratio, and its high trigger voltage without a dedicated adapter is definitely to be avoided with a digital camera. The runner-up Sunpak hammerheads (455 and 555) probably aren't worth their weight for a paltry 1/3rd stop over a speedlight either.

The behemoth 60CT-4 can be got rid of too.

 

For me, the quirky Osram/Wotan S440 is a keeper. As is the Metz 45CT-4 with a useful 2/3rds extra stop.... maybe; since boosting the digital ISO by 2/3rds of a stop is no big deal these days.

 

So, there's my evidence. It's up to you, but all I'm saying is; don't be impressed by the size and weight of old hammerhead flashes. Size really isn't everything.

 

And I haven't even touched on the niceties like built-in diffusers, allowable head rotation, nasty tilt detents, automated exposure options, ability to fit in a softbox, mounting convenience, etc.

Nice thread title.

Too bad you live in the UK otherwise I would want your 60CT-4.

There was another Rodeo Joe here who used to scoff at unnecessary tests and comparisons of old Classic Manual Cameras. Wonder where he went?;)

 

I would only like this more if there were pictures of the different hammerheads!

hmmm

Sounds like a fun experiment.

Maybe I should dig out my potato mashers also (that is what we called them).

Don't have as many, Honeywell Strobonar 800 (my old workhorse), and three different Sunpaks (I think I have a 622 but don't remember what the other two are).

There was another Rodeo Joe here who used to scoff at unnecessary tests and comparisons of old Classic Manual Cameras. Wonder where he went?;)

I do not recall which version of the Metz 60CT they tested but they noted that it measured around GN 50. They did all their flash tests at 1/250s and re-tested the Metz at either 1/60s or 1/30s (which also was the X-sync speed of my old Pentax67). Then it measured significantly better at around the claimed output, giving about a third of a stop more light. In addition to measuring colour temperature, they also compared the output just when the ready light came on to when it has been on for 30 seconds and also compared vignetting at the extreme edge to center for all flashes at various focal lengths (for those that came with wide-angle panels or zoom heads).

I believe he moved on to bigger things.;) He is usually found in the Nikon forum balancing out the threads by pointing out flaws in just about every Nikon product ever made...

 

Speaking of comparisons and methodology, what shutter speed did you use, Rodeo Joe? I remember back in the 90s when a Swedish magazine tested a Metz 60CT in a large test featuring most of the flashes on the Swedish market at the time.

I do not recall which version of the Metz 60CT they tested but they noted that it measured around GN 50. They did all their flash tests at 1/250s and re-tested the Metz at either 1/60s or 1/30s (which also was the X-sync speed of my old Pentax67). Then it measured significantly better at around the claimed output, giving about a third of a stop more light. In addition to measuring colour temperature, they also compared the output just when the ready light came on to when it has been on for 30 seconds and also compared vignetting at the extreme edge to center for all flashes at various focal lengths (for those that came with wide-angle panels or zoom heads).

 

I don't know if it makes a difference but the Metz 60CT4 at full power has the duration somewhat longer than 1/250. When I test the GN with a flash meter set at 1/60 the 60CT4 consistently deliver less power than rated.

Speaking of comparisons and methodology, what shutter speed did you use, Rodeo Joe?

1/250th, except on a couple of frames when I accidentally 'bodged' the speed to 1/200th. It was reset to 1/250th after I noticed.

 

Any flash that has a duration longer than 16 milliseconds deserves to get cut short in mid sentence!

 

And one of the reasons for using flash is that it should eliminate or greatly reduce the risk of camera shake or subject movement. 1/60th shutter speed and flash duration won't.

He is usually found in the Nikon forum balancing out the threads by pointing out flaws in just about every Nikon product ever made...

Not every one. Only my D800 that's gradually falling apart, my D7200 that had badly adjusted AF and suffered a shutter failure after less than 1000 frames, and an F4 that was rendered completely non functional by a small crack in the (plastic) top next to the frame counter.

 

The F2 was a very nice camera. Shame it all seems to have gone downhill since.

Edited February 22, 2021 by rodeo_joe|1

I just checked the flash duration of the 60CT-4 using my digital storage oscilloscope. It extends to just over 10 milliseconds, with t0.1 at almost exactly 6ms. (Slowest I've seen so far!)

 

The figures for the Osram S440 were a total duration of around 8ms and t0.1 = 4.5 ms.

 

The YongNuo speedlight clocked in at a sprightly 4 ms total duration and just over 3ms for t0.1.

 

T0.1 corresponds to capturing over 90% of the total light energy from a flash. Or 1/8th of a stop short of maximum.

 

So even with the 60CT-4, a shutter speed of 1/125th (=8ms) should gather all but a tiny fraction of a stop of its total light output. No need to use a shutter speed of 1/60th; although in an averagely well-lit room, the extra ambient light at 1/60th might well boost the total exposure by 1/3rd of a stop.

I just checked the flash duration of the 60CT-4 using my digital storage oscilloscope. It extends to just over 10 milliseconds, with t0.1 at almost exactly 6ms. (Slowest I've seen so far!)

 

The figures for the Osram S440 were a total duration of around 8ms and t0.1 = 4.5 ms.

 

The YongNuo speedlight clocked in at a sprightly 4 ms total duration and just over 3ms for t0.1.

 

T0.1 corresponds to capturing over 90% of the total light energy from a flash. Or 1/8th of a stop short of maximum.

 

So even with the 60CT-4, a shutter speed of 1/125th (=8ms) should gather all but a tiny fraction of a stop of its total light output. No need to use a shutter speed of 1/60th; although in an averagely well-lit room, the extra ambient light at 1/60th might well boost the total exposure by 1/3rd of a stop.

Given the vintage technology of the Metz flashes, it probably dated from 1960's SLRs that mostly synced at 1/60. The long duration wasn't a big problem at a sync speed that slow.

Short duration is not the purpose of flash units. Providing enough light is. Portable units are a compromise between power and portability. And less power means shorter durations. But that never really was the aim.

Short duration is not the purpose of flash units. Providing enough light is. Portable units are a compromise between power and portability. And less power means shorter durations. But that never really was the aim.

 

I recall that the short duration of the flash was some of the advertising.

Well, flash, by nature, is over in a flash. But how long is that?

It was invented to have a powerfull source of light. Powder. Then better powder. Then the stuff encased in a bulb. Then electronic.

Edgerton made a point about the short duration. But even today, when you want and need power, you will not have particularly short flashes.

...but even today, when you want and need power, you will not have particularly short flashes.

Ummm, a lot of studio gear manufacturers make a big deal out of their extremely short flash durations. With hundreds of watt-seconds of light energy available.

 

While those old Metz lumps can be used at FP synch with little fall off across the frame. About their only good use today IMO.

 

FWIW. Here's the scope trace of the 60CT-4, along with the integral of its output to help assess duration against total exposure:

And a similar graph for YongNuo's YN560. Note the timebase is 1ms per division here, and not 2.

With only 1 stop in light output between them, I think the trade off in loss of weight and recycle time is well worth it. Plus the cheapness and availability of an AA cell power source, lack of trailing power cable, and a multplicity of other advantages.

So the YN560 has the duration about half that of the 60CT4.

Ummm, a lot of studio gear manufacturers make a big deal out of their extremely short flash durations. With hundreds of watt-seconds of light energy available.

 

Yes. And until not so long ago, hundreds of Ws meant burn times around 1/60 of a second.

1/10,000 or shorter could be had, but only if you make do with not so many Ws.

And until not so long ago,

The 1970s?

That's 50 years ago now.

 

Flash duration is mainly regulated by the ESR (Equivalent Series Resistance) and self-inductance of the storage capacitor(s).

 

In ye olden days, the design philosophy was to use dustbin-sized capacitors with an equally large ESR. Until it was realised that using smaller capacitors in parallel was just as space-efficient, more cost-effective, and also reduced the ESR. With a consequent reduction of flash duration.

 

The connecting cable between power-pack and flash head of the 60CT series does nothing to reduce flash duration either.

So the YN560 has the duration about half that of the 60CT4.

As you can see. Almost exactly half.

Today, Rodeo Person. 3200 J at 1/238 s. (Broncolor). For instance. Lightning fast (how long does a lightning flash take?).

Ye olden days are still going on apparently.

 

Flash duration depends on how much energy you want. More does not mean a brighter, but a longer flash. A pocketable hot shoe flash is not an example of a high power unit.

Today, Rodeo Person. 3200 J at 1/238 s

That's 21.33 times the light energy of a 60CT-4 in 4.2 milliseconds. About the same duration as that YN560 I showed above, and with nearly 43 times it's energy.

 

All of which gives the lie to:-

More does not mean a brighter, but a longer flash.

Patently not!

Lightning fast (how long does a lightning flash take?).

Huh?

Who mentioned lightning fast? And what does a natural phenomenon have to do with the engineered production of a short burst of light?

Edited February 27, 2021 by rodeo_joe|1

Brighter I think depending on the voltage. For a flash with the same WS rating one can either use high voltage or large capacitor. High voltage would give brighter but shorter duration.

The high voltage simply overcomes ESR better. If you reduce ESR, then there's no need for a high voltage, unless the flash-tube needs to be made lengthier for some reason.

 

Most flash units these days use no more than 350 volts on the storage capacitors. Otherwise controlling the flash pulse with IGBTs or Thyristors gets expensive.

 

The ridiculously costly Profoto Pro-10 offers 2400 Joules with a t0.1 duration of only 2.5 ms at full output. So flash duration definitely isn't proportional to output energy.

 

It's only when the flash exposure is regulated down from full 'power' by using electronic control that the duration gets shorter. Exactly in the same way that the camera shutter speed works. Except the flash duration has to be regulated to work according to the flash tube's exponential rise and fall curve. And that's why I showed the integral exposure curve on the graphs above.