Problems with Smart Auto Flash - Metz MZ40-x and K10D

Started Apr 26, 2007 | Discussions thread
blink_too_fast Regular Member • Posts: 187
3702M2, P-TTL, erratic exposures & everything Metz !

I finally have a 3702M2, so I guess you want to know how it works.

I have also worked out why the flashes sometimes overexpose and how to fix it immediately and perfectly. Short answer is leave your adaptor in rear sync.

I have…

(OK, there’s an underlying eBay obsession going on here…)

*istDS
K100D

32CT3i
32CT4
40MZ1i
40MZ2 (several of these)
40MZ3i
44MZ2
54MZ3
54MZ4

28CS2

301 (several of these)
372
3701
3702M
3702M2 (finally - only took 4 months!)

3083 x2

307A (these are cool)
305A (so are these, but you'll be lucky to find one)
305S (and if you do, you'll need one or two of these)

G16
3002A
Bracket

So, what combination does and does not work?

The only P-TTL combination is the 3702M2 & 54MZ4. Nothing else works as P-TTL. Not the 40MZ1i/3i. Not the 54MZ3. Not the 44MZ2. Nothing. Got it?

P-TTL also works in rear sync mode.

With the 3701/3702/3702M2 & 40s/44/54s set in A-mode, I can set the 40s/44/54s to act as a controller to control the 3083s. They respond appropriately with the 40s, the 44, and the 54.

With the 301/372 & 40s/44/54s set in A-mode, I can set the 40s/44/54s to act as a controller to control the 3083s. They respond appropriately with the 40s, the 44, and the 54. Smart-A does not work, so need to dial in the ISO & aperture manually

With the 372/3701/3702/3702M2 & 40s/44/54s set in TTL-mode, I can set the 40s/44/54s to act as a controller to control the 3083s. They respond appropriately with the 40s, the 44, and the 54.

With the 3702M2 & 54MZ4 set in P-TTL mode, I can set the 54MZ4 to act as a controller to control the 3083s. They do not respond. THEY DO NOT WORK. NOTHING. Use A mode (above) or force TTL mode, below.

I cannot select the 3702M2 & 54MZ4 to basic TTL mode, but I can force it by knocking the lens off of A on the aperture, or in the case of some lenses, twisting the whole lens on the mounting plate of the camera so the contacts do not line up. Be careful your lens does not fall off if repeating this trick. It's alright as long as you don't forget it and walk off with it unlocked.

The 305 & 307 only work with the 301 & 372. They do not work with the 3701 or 3702s

When using the 305 and/or 307, flash behaviour is exactly the same as the 301 or 372 alone.

The 32s only work with the 301 & 372. They do not work with the 3701, 3702s or 3083
The 40s/44/54s and G16/3002 work with any of the adaptors
When using the G16/3002, flash behaviour is the same as with the adaptor alone.

The 372 only works in first curtain / front sync

The 3701 & 3702s work in both front and rear syncs, but only expose reliably in rear sync. In front sync the flash can fire at both the front and rear curtains. This happens if the first discharge is small enough, your batteries are fast enough and the shutter speed is slow enough for the flash to recharge between the two events. In this case the shot will be overexposed. In TTL mode the second discharge seems to be a full load for everexposure is extreme. In A mode the second discharge is a second correct dose so overexposure is about +1eV and not always noticed, especially if the flash exposure is set to -1eV. However, this is an inconsistent bodge based on frame by frame exposure settings and battery condition. Because the flash must recharge between the two events, it happens most often when firing directly or in higher ISO or larger apertures when less flash is initially needed. It does not tend to happen when bouncing the flash as the initial blast is larger and the flash tends not to recover. Set the camera to M, 1 second, 1st sync, and you'll see what I mean.

The 3702M2 & 54MZ4 does expose reliably in first sync. I reiterate: Only the 372+anything or 3702M2+54MZ4 expose reliably in first sync.

The 301 adaptors can be wired together with 2.5mm jacks and two core cable to synchronise them.

I have never tried using the 305A&S to make multiple controller units to see how the 3083s respond. But there's no point. Just make one of them the controller and leave the others in A or TTL.

The istDS does everything above
The K100D does not support TTL, so only does the A & P-TTL things above

If you try to use P-TTL on any combination other than the 3702M2 & 54MZ4 the flash discharges fully (Same as M set to 1/1)

Using K100D & A mode on the flashes is just as good as TTL mode anyway (unless using a filter) (remember to set to rear sync to avoid double flashes andoverexposure)

28CS2 works perfectly as it should.

In summary, everything works as it should except non P-TTL flashes on P-TTL cameras sometimes overexpose in first sync. Leave them in rear sync.

I might create a diagram / table / figure showing all this. Or I might not. Depends if it rains this week.

Of course, my battery usage is pretty high. I recommend Googling BC900 battery chargers. They're great.

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