Metz Mecablitz M400 for Micro Four Thirds review

The Mecablitz M400 is a stylish, compact flash unit with wireless TTL metering, full manual control and a built-in video lamp. Is it any good?

Metz Mecablitz M400

I have been playing with Metz’s pint-sized flashgun, the Mecablitz M400, for the last few months.

The M400 fits into the same niche as the Nissin i60A (and i40), the MeiKe MK310 and Godox TT350. That is, it is a small-form factor shoe-mount flash with features more conventionally found in big, flagship flashes.

Unlike the Godox and the Nissin, the Metz doesn’t have built-in radio functions, but it has just about everything else you could want in a system flash, including full manual control, wireless optical master and slave modes, TTL, a fully tilting, swivelling head and a bonus video light. More impressive still is the range of cameras this little flash supports: it’s available for Canon, Nikon, Micro Four Thirds, Pentax, Sony and Fujifilm.

I was sent the Micro Four Thirds version, and have been testing it with my Panasonic Lumix GX7. Some features are camera-dependent, so your experience with other flash–camera combinations may vary.

Metz Mecablitz M400
The head tilts, swivels and includes a flip-down diffuser and bounce card

Whereas Nissin decided to go with a more retro-styled design featuring a physical mode dial, the Metz M400 is thoroughly modern, with a sleek, distinctive appearance. Everything is controlled from a futuristic-looking OLED screen and an accompanying directional pad.

Despite what might look like a fairly spartan set of controls, the Metz M400 is packed with more features than you could possibly imagine. You can customise everything from displaying distances in metric or imperial units, to adjusting the brightness of the display, toggling sleep mode, the AF-assist beam and more.

Metz Mecablitz M400
When the flash faces forward and can communicate with a camera, the screen displays an estimated flash range at the current power setting

Though unconventional, the user interface is clear and intuitive. Only one or two things had me reaching for the manual. Speaking of which, there is no printed booklet supplied in the box; you get the flash itself, a soft drawstring case and a tabletop stand that doubles as a tripod mount.

There are half a dozen different operating modes available in the menu, though this varies according to whether you have the flash on or off-camera.

  • Auto is an oldschool non-TTL auto mode that automatically computes brightness using a sensor on the front of the flash.
  • TTL is a more sophisticated automatic exposure mode that uses pre-flashes measured through the lens of the camera. You can adjust flash exposure compensation up or down in 1/3-stop increments.
  • M, or Manual mode, is where I spend most of my time. It offers output control from full down to 1/256 power, in 1/3-stop increments. This is an unusually precise level of adjustment—most flashes only offer down to 1/64 or 1/128, and even then usually on top-of-the-range units.
  • LED is its own mode, which means the continuous lamp and the flash tube can’t be used simultaneously. So no ‘modelling lamp’ or ultra-bright autofocus-assist lamp, unless you want to be switching back and forth between flash and video lighting mode. The LED has several levels of output adjustment but this can’t be controlled remotely.
  • Servo is a basic optical slave mode. You can choose to turn pre-flash suppression on or off,
    and there is a nifty “Learn” feature that’ll teach the M400 to synchronise correctly with your flash system, no matter how many pre-flashes it uses.
  • Slave is a more advanced optical slave mode. From the flash you can select the wireless channel and group, then you can trigger and control it from a master flash unit, assuming you have one for your system. I was able to use the built-in flash on my GX7 and adjust power and switch between Manual and TTL modes with ease, and didn’t have any problems synchronising it indoors, though I would use a radio trigger for anything nontrivial.
  • “F1” and “F2” are the only operating modes that weren’t immediately intuitive. They stand for “Favourite 1” and “Favourite 2”. Set up the flash however you want in another mode, then switch to this and you have the option to save all your settings. You can then reload them later.
Metz Mecablitz M400
In advanced optical slave mode, you can trigger and control the M400 from other Olympus/Panasonic master flashes
Metz Mecablitz M400
Select ‘Manual’ from the menu and the screen displays a QR code linking to an online instruction manual

I mentioned that no manual was included in the box, but that doesn’t mean it’s unavailable to you: in the settings menu of the flash is a “Manual” option, which when selected displays a QR code on the screen linking to an online PDF of the user manual. This sounds like a great idea, but I realised I never use QR codes and it was quicker to type into my browser than to find an app that could read them. Nonetheless, a nice touch.

The instruction manual is quite clear and well laid-out, though contains a few trivial typographical errors, as well as (at least in the English and Dutch sections) one or two clauses that they simply forgot to translate from German — I understand what “Synchronisation ohne Vorblitz” means (page 141) but maybe not everybody will.

Specs-wise, the manufacturer promises recycle times as quick as 1.5 seconds with NiMH batteries at full power. I measured around the same. There is no way to speed this up, as there is nowhere to plug in a high-voltage battery pack. This isn’t really meant as a machine-gun type flash, though.

There are 12 zoom settings: 12mm (with the wide-angle diffuser), 24, 28, 35, 50, 70, 85 and 105mm, with listed guide numbers (at Iso-100) of 14, 21, 22, 25, 28, 33, 37 and 40, respectively (−2 stops in high-speed sync mode). While I can’t reproduce the GN exactly, I found from experience that the M400 offered more than enough power — even when using relatively small apertures and bouncing off large walls for portrait work, I was only using around 1/4 power.

The LED seems pretty bright, but I really don’t do much video work so never really used this in anger. I’m not sure who really uses these but I guess it’s nice to have.

There is no audible whine when the flash recycles and I only had to change the batteries after heavy use.

Metz Mecablitz M400
The micro-USB port, used for firmware updates, is found inside the battery compartment

One thing that I wasn’t able to get working was high-speed sync. On my Panasonic GX7, I obtained clean frames up to 1/400 second shutter speed, then feathering at 1/500 second and gradually increasing black bars until a completely dark frame at 1/2,500 second. Then, switching from M mode into M FP mode, exactly nothing happened — I got exactly the same results. Synchronisation was similar in TTL versus TTL FP modes. Perhaps the GX7 doesn’t support high-speed sync or I am doing something wrong. It didn’t bother me but you might want to check this carefully if HSS is important to you.

Another minor niggle: there appears to be no test button on this flash. The only way that I could get it to fire a test pop was via the test button on a radio receiver attached to the hotshoe, or by simply taking a photo.

Metz Mecablitz M400

Overall I found the design of the M400 very appealing, the performance satisfactory and the weight and size of the unit itself complementing my small Micro Four Thirds cameras rather well. The head swivels 180° left and right, which makes this very usable as an on-camera flash for events photography, and as an off-camera flash it produced easily enough light for the simple situations in which I tried it.

I was a big fan of the Nissin i40 as an on-camera flash and the Metz M400 is even better, offering more precise controls and advanced features at a slightly higher price point of £200. I would highly recommend it if you’re looking for a flash to use on-camera with a small mirrorless system.

Even smaller (and cheaper) flashes are available, such as the Godox TT350 and MeiKe M320, but these only take two AAs so are less powerful. Panasonic’s own offering, the FL360LE, is about £50 more expensive and not nearly as compact.

Metz Mecablitz M400 example photo
Example self-portrait. Iso-200, 1/200 second at f/5 on Lumix GX7, 61mm. Lit with the Metz M400 at 1/4 power bounced off a wall to the left, and another flash, behind the subject, pointing at the background

That said, I don’t use TTL very much and mostly use flash off camera, where size is less important. As such I would probably go for a slightly beefier manual flash, but that’s my personal preference rather than anything against the M400.

The Metz Mecablitz M400 is available now for around £210 or $280 on Amazon, at Adorama and B&H Photo.

Thanks to Metz Mecatech for supplying us with a sample unit for this review. For more information, visit the manufacturer’s web site.

David Selby
David is a keen photographer and has been editor of Lighting Rumours since 2010. When not writing about lighting, he works as a data scientist at the University of Manchester, UK.