Originally posted by HermanLee I am confused as to which flash I should get between Pentax AF540FGZ or Metz 58 AF1 or Promaster 7500.
Someone mentioned that with Pentax 540, we have to set the f and ISO everytime manually. Is that correct?
Does it mean if I use a lens for ex: Sigma 17-70mm 2.8-4.5 + K100D + 540FGZ and set the ISO in the camera to auto then the flash won't be able to follow the camera's ISO setting?
Who said this?
In P-TTL mode, you don't have to do anything on the flash. Everything is communicated between the camera and flash. All I've had to do is turn up FEC to +0.3 to 0.7 and I get very reasonably exposed direct or bounce flash shots almost every time.
As it is with the other P-TTL flashes, they're designed to calculate the flash intensity required with the settings you've got on the camera. So it doesn't matter what mode you're in (except M/B mode), P-TTL theoretically takes the thinking out of working out the flash settings needed to make it totally automated.
As you might hear though, even from me, P-TTL doesn't always give you the results you want, so you put it in M mode to get a consistent flash intensity... All depends on what you need it for. I did quite well with a totally manual flash for a while, which costed me a whole $30, but I wasn't astute enough to get the right settings at the beginning without a little trial and error.
But rest your mind, P-TTL means everything is automated, no need to set anything (if you want that).