I know the *istD does some compensation on the AF360FGZ - bit weird seeing it in action. It confused me for a while, until I downloaded and English manual and had a read about this. At first I thought I might have had a fault as the flash kept telling me I had a 58mm lens when I had the 24-90 set to 90. At the wide end it looks normal, presumably because the flash cant go wider than 24, so it seemed a bit odd.
Does an Ftz in the *istD do a similar thing? I would have thought that the flash would be set to 1.5* the 35mm focal length to cover the new effective FOV, rather than 2/3rds of the 35mm length, but the manual says: The AF360FGZ will automatically convert the field angle differential between 35mm and the *istD format resulting from the focal length of the lens you are using. (When using FA J, FA, or F lenses) Display the format size for the *istD during the exposure metering timer of the camera is turned on when combining the AF360FGZ with the *istD. (It returns to a 35mm format display when the exposure metering timer is turned off.) Lens - AF360FGZ used - display 85mm - 58mm 70mm - 48mm 50mm - 34mm 35mm - 24mm 28mm - 19mm 24mm - 16mm 20mm - 13mm Although I am sure it doesnt go below 24mm as I said, so they got the manual wrong there. I stillcant quite get my head around it now I think again, but I thought I had managed to understand why after alot of thinking last time. The logic escapes me now though, so maybe I gave up - firmware version 1.1 anyone? To me it looks like Pentax have got it wrong. A 24mm lens on the istD should require a flash angle equivalent to a 35mm lens.
