What is the difference between the mecablitz 45 CT and mecablitz 45 CL units?

Metz flash units can also be used with digital cameras. These cameras can be subdivided into three groups according to the type of flash connection they feature.
Group 1: Cameras without accessory shoe, but with built-in flash.
Group 2: Cameras with sync contact (X-contact or hot shoe).
Group 3: Cameras with hot shoe and special flash functions.

Group 1: Cameras without accessory shoe can still be operated with a flashgun featuring a slave trigger unit and automatic flash mode. “Metz mecablitz 28 CS-2 digital” is such a flash unit as it has an integrated slave unit. Furthermore, the SCA-3083 digital slave adapter can be used with all flash units that are compatible with the SCA 3002 system. It is only necessary to select the given slave function “WITH” or “WITHOUT” pre-flash suppression.

Group 2: All current Metz mecablitz flash units with sync cable connection or standard foot can be used with digital cameras featuring an X-contact or hot shoe. Here, too, the flash unit should permit the automatic flash mode.

Group 3: Cameras with special “dedicated” flash functions, such as TTL flash control, require a flash unit with an SCA adapter system or with a corresponding camera connection so that the additional special functions can be used. Normally, these cameras can also be used in conjunction with Metz flash units with a standard foot and in automatic flash mode, except that in this instance the special flash functions can no longer be used.

All current Canon digital cameras with a hot shoe feature so-called E-TTL flash control in place of the standard TTL flash control. Fully automatic operation with these cameras requires flash units that feature this particular flash mode. Suitable flash units see flash light recommendation.

The SCA 3000 flash units, for example mecablitz 32 MZ-3, 40 MZ-.. or 50 MZ-5, aren’t loaded with this special E-TTL flash control. Therefore this flash units only can be used at automatic flash mode or manual flash mode with the Canon digital cameras . Normally we recommend using also the adaptor SCA 3102 for connection. Thereby the particular aperture is also manually adjustable at mode "AV" or "M" at the camera.

The adapters of the Metz SCA adapter system are constantly being updated to match new cameras with additional or modified flash functions. For this reason the new adapter models are continuously numbered (M, M2, M3 …). The latest adapter model always replaces the previous one and is usually downward compatible (exception: SCA 3402; see also SCA adapter search). The adapters of the SCA 3002 system can generally be upgraded by way of firmware update.

SCA 300 is an analog system, whereas SCA 3002 is digital. As a result of the additional exchange of digital data further special flash functions become possible when these cannot be set on the camera concerned. The flash units of the SCA 3002 system are downward compatible, and can, therefore, also be fitted with SCA-300 adapters. However, SCA 3002 adapters are not necessarily compatible with SCA 300 flash units. For instance, the SCA 3000 C connecting cable is required to match SCA-3002 adapters with handle-mount flashguns of the SCA 300 system, but not all the functions of the given adapter will then be available with this connection.

Extension cables and leads of the Metz SCA adapter system for off-camera flash can be problematic. The information transmitted by such cables involve low-level pulses that are very susceptible to external influences on the cable. Consequently, the disruptions can increase with the length of the extension.

Moreover, line inductivities and switching capacities can also be of importance. The longer the cable, the greater the influence on the form of the transmitted pulses, thereby giving rise to faulty exposures. Direct cable extensions are therefore not necessarily practicable.

We recommend the TTL-Multiconnector SCA-305 A for longer line lengths in conjunction with an SCA-300 adapter. This active TTL distribution system is simply slipped onto an SCA-300 adapter. On account of the longer line lengths, up to three flash units can be simultaneously connected to one TTL-Multiconnector. The SCA-300 E intermediate adapter, together with the SCA-3000 C connection cable, also enable the TTL-Multiconnector to be used with SCA-3002 adapters.

A battery case supplies a flash unit, such as the Metz mecablitz 45, with 9 V power (6 x 1.5 V). However, if NC or NiMh batteries are loaded in the battery case, then only 1.2 V (6 x 1.2 V = 7.2 V) will be available on account of the cell’s lower voltage rating. This results in a significantly smaller guide number, thereby greatly reducing the maximum flash range in automatic and TTL flash mode. It also means that manual flash operation becomes impracticable because a guide number is no longer available to calculate the camera’s aperture setting.

The contacts of our NiMh battery pack 45-56 are located at a different point so that the existing voltage difference is compensated. The NiMh batteries incorporated in this pack are special cells that are rigidly connected with metal strips to cope with the high power consumption of the flash unit. Consequently, an empty NiMh battery case cannot be loaded with other commercial rechargeable batteries.

Furthermore, the high currents of an inadvertently incorrectly loaded NiMh battery may destroy the electronic circuitry of the flash unit. Consequently, we urgently advise against the use of NC or NiMh batteries in the battery case.

Regretfully, the Metz mecablitz 45 CT-1 does not yet have the connecting capabilities of the Metz SCA adapter system. Consequently, no corresponding adapter is available for combination with autofocus cameras. The Metz mecablitz 45 CT-1 can therefore only be connected to such cameras with a standard synchronising cable.

Furthermore, it is necessary to note that Metz mecablitz 45 CT-1 units featuring a model number that is smaller than 534 000 are fitted with a so-called high-voltage ignition circuit. These flash units must not be directly connected to modern cameras as this could even damage the camera!

All other flash units of the Metz mecablitz 45 CT and 45 CL series feature a low-voltage ignition circuit in keeping with the current standard.

Flash units of the Metz mecablitz 45 CL series are successor models of Metz mecablitz 45 CT units, and they feature a modified method of flash readiness indication. Accordingly, flash readiness is indicated by a light-emitting diode on Metz mecablitz 45 CL units, whereas flash units of the Metz mecablitz 45 CT series feature a glow lamp for flash readiness indication. Furthermore, Metz mecablitz 45 CL flash units have standard connecting sockets.