Originally posted by A H Thompson The Pentax AF360FGZ was recommended in a previous post and is probably what I will get.
Just FYI but the AF360FGZ is a world apart from the Vivitar 285.
The AF360 is a Pentax flash compatible with Pentax's P-TTL communication protocol. It can be used both on camera and off and triggered off camera by the camera using an optical communications link. In other words, this flash is designed to communicate and work with Pentax cameras automatically.
The Vivitar 285 is an old film era flash that will work in manual mode, assuming the trigger voltage is not so high it fries your camera. Hence my word of caution above. It would be safe to use off camera with radio triggers and on camera in manual if the trigger voltage tests ok.
Originally posted by A H Thompson I am not familiar w Cactus products.
Cactus makes both radio triggers and flashes that work with just about all camera brands. However, the term 'radio trigger' usually means a trigger for the flash when used off camera. So the trigger transmitter goes on the camera hot shoe and the receiver on the flash. When you press the camera shutter button the trigger also fires the flash which might be 10 to 100 feet away. Technically it can also be used in a different mode that can remotely trigger the camera but this is not the usual mode of operation.
Originally posted by A H Thompson alternative to a Pentax cable release or remote whether using flash or not?
Sort off. As in yes it will do that, but that is not it's primary purpose and a standard cable or wireless shutter release is likely to be much cheaper and simpler than using a flash trigger to fire the camera.
I suspect you need to do some research and study on flash in general before making any purchase decisions. You should determine if you want P-TTL flash communication or manual. And whether you want to use the flash on camera or off camera. Those things will determine what gear is needed.