I have a Pentax 645N which i love. I have been using it with a Metz flash by setting to the Xsync and letting the camera adjust the aperature. The flash is TTL. Can the camera sync the flash if I set the shutter to 1/30 second and use a tripod? Or will it only syn when the dial is set to the red X-SYNC position which appears to tie you in to 1/60 sec. Second question is this: When using a flash the shutter is 1/60 and the aperature is set by camera for available light. When the available light drops below the widest aperature, which was f2.8 in my case, the camera metering will let you take a pictures at 1/60 f2.8 no matter how low the light. Question is this: Assuming the flash can supply the light and is set for TTL will the pictures get enough light to come out?

-- Al S, (sas33@psu.edu), February 26, 2001

Answers

I'm only a little familiar with the 645N, but as a matter of general flash question I'll offer my two cents.

First, look at which mode your camera is set. The 645N has a maximum x-sync of 1/60, and can be used at slower shutter speeds in shutter priority and metered manual modes only. Therefore if you're attempting this in aperature priority or full auto mode, you may be parked at 1/60.

I don't know the low end of the flash sync on the 645, but if you want to take 1/30, than you will have to set the camera shutter at 1/30 (in shutter priority mode) and the flash should sync.

I don't know if this helps, or confused you even more. I know I am :)

-- Scott Laughlin (scottlaughlin@mindspring.com), February 26, 2001.