In May 2009 I bought a Mecablitz 58 AF-1 “digital” flash. Normally I put links to the description of photographic components when I mention them, but it's no longer in production, and Mecablitz clearly don't want to waste space on their web site for it.

That's not that serious. The replacement model is the 58 AF-2 digital (“for the ambitious”). It's almost identical, but the naming is confusing. They do mention it on the firmware download page.

On 12 January 2013 this unit failed: the flash tube exploded. The repair costs exceed half the new price, which makes it impractical. I can get a new tube relatively cheaply, but as of the time of writing I haven't been able to open the flash head to get at the tube. It seems that this is a relatively common occurrence.

The remainder of this page consists of random observations about the unit.

Focal lengths

The flash reflector adapts to the lens focal length. Although my model is for Olympus and Panasonic only (Four Thirds sensors), the focal lengths are given in (rough) equivalent focal lengths for full-frame 35 mm cameras. The manual states:

The following zoom positions are available: 24 - 28 - 35 - 50 - 70 - 85 - 105 (focal lengths in mm) (corresponding to 35 mm format).

When using the wide-angle diffuser the main reflector is automatically moved to the 24 mm position! Because of the wide-angle diffuser, 18 mm appears on the display.

This really corresponds to focal lengths of 12, 14, 17.5, 25, 35, 42.5 and 52.5 mm, or 9 mm with the diffuser. If that wasn't confusing enough, there seems to be another setting. If you push the wide-angle diffuser in all the way, the display changes to “Manual 16”, suggesting 8 mm focal length. I can't see how that can work. Maybe it's a position for an external diffuser, but I haven't seen any evidence of such an accessory ever having existed.

Guide numbers

The guide number is specified as 58 (thus the model name). You get this guide number at maximum focal length (52.5 mm, corresponding to 105 mm on a full-frame camera) at 100/21° ISO and with a shutter speed of 1/125 s or lower. That's the time it takes the flash tube to fire at full power. Interestingly, the documentation states that half power lasts only 1/650 s, and they don't say what the durations are for intermediate powers.

Remote flash sensor

The remote flash sensor is on the front of the unit, so it only fires if you can see the front: