Re: Overexposure of PZ1+

[Joe Wilensky]

So here's a question: Why do the PZ-1 and later cameras need an "A" lens in order to use evaluative/matrix/segmented metering? If they can spotmeter with the older lenses, why do they need an "A" lens and its transmitted information about maximum aperture to make a decision about whether or not to weight the exposure to compensate for backlighting or sidelighting, for example? Is there a simple explanation for this?

On another note, why can the Pentax autofocus cameras provide autofocus confirmation with manual-focus A, M, and K lenses, but not with screwmount lenses via the adapter? In the case of the M and K lenses, the only information being sent from lens to camera (that's absent with the screwmount lens/adapter combo) is the aperture simulator coupling -- why is that necessary for focus confirmation? I would assume that based on the lens speed and lighting conditions, either there's enough light to confirm focus or there isn't.

Joe

 >[EMAIL PROTECTED] writes:

 My Z1 spot meters with all my pentax lenses, K,M,A,F,FA.

[EMAIL PROTECTED] wrote:

I don't know. I'll go home and try it, but I remember trying
to get my M's & K's to spot meter and they didn't. They will
say SPOT metering is ON in the viewfinder, but the exposure
won't change.

Just tried my PZ-1p with a K50/1.4 and both spot and center-weighted
metering work - and the exposure definitely does change (I metered in a
dark room with a small window in the center).

--
Mark Roberts
Photography and writing
www.robertstech.com