Metz 45 CT-4 High Voltage with Fractional Power

[jon_erik_lido]

<p>I have a Metz 45 CT-4 that I picked up used along with a Lumedyne Minicycler high voltage battery pack and the appropriate HV cable. The Metz manual says to leave the 45 CT-4's power switch in the off position when using the AC power adapter. (It doesn't say anything about the Lumedyne, of course, but I assume they provide the same power.) No further explanation is provided in the manual. There are no dire warnings about using it in the "on" position, and no consequences of doing so are listed.<br>

The problem is, with the flash "off" it seems to only fire at full power, even in the 1/2, 1/4 power and "auto" positions. These modes work fine when the flash operates on AA battery power, however. So, when running on the Minicycler I've tried turning the power switch "on". In this case the flash seems to get the fast cycle times from the Minicycler, but the various modes still work.<br>

Is this safe to do? I noticed that the batteries that I've used to do this test stopped accepting a charge shortly after. Coincidence? What's going on here?</p>

[danny_wong2]

<p>The AC and Lumedyne MiniCycle put different voltage into the flash.<br>

The AC or AA batteries are still needed with the Minicycler to power the flash's control circuits. The MiniCycler works by recharging the capacitors directly with 330V current and therefore the fast recycling time. Without the control circuit then you only get one setting, full.</p>

[jon_erik_lido]

<p>Thanks, Danny! So the Minicycler/Metz combo is intended to be run with the AA batteries installed an the unit turned on. I did not realize (since I don't own one) that the AC adapter (unlike the Minicycler) provided power to both the control circuit and to the capacitors. Good to know it is safe to use the Metz with the control circuit turned on. The flash would be barely usable if it was limited to full power output only!</p>