Flash with digital cameras

I have already mentioned a few restrictions when using flash with digital cameras. This is a summary of these points:

With modern digital cameras (DiMAGE 5, 7, 7i, 7hi, A1, A2, A200, Dynax/Maxxum 7D and 5D, Sony Alpha DSLRs) TTL-OTF metering is not possible. This has a number of consequences:

The current Minolta AF/Sony Alpha flash system has grown quite complex, and it is not very well covered in the manuals. That's because this would involve to cover some very basic concepts, and there are many combinations of cameras and flash units with different capabilities that would have to be documented. What I try here is to explain how the Minolta flash system works in detail. This compendium assumes that you have some basic knowledge of photography, ie. you know that an aperture is and you know how a shutter works. Sony has taken over further development of the Minolta A mount (now Sony Alpha mount) and has also kept the Minolta AF flash system with their new DSLRs. When this compedium says "Minolta", the same is true for "Sony Alpha", too, except when noted otherwise.