The P67 II Exposure system

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I was just asked about the 67II exposure compensation system and I had to dig a little, both in the manual and by experimenting, for the answer. Here's the info for any who may ask. The exposure compensation system, of -3EV to +3EV in 1/3EV increments, biases the meter and affects only the meter indication in manual mode. Whatever you set for aperture (1/2 stop increments) or for shutter speed (normal increments) will be used when the button is pushed. The metering is virtually stepless in that bars light up over fixed reference bars indicating the the amount of over or under exposure the settings have from what the meter thinks is accurate. Your ability to decipher this graphical method depends on your own vision. The value the meter wants is what is biased by the compensation. In AE mode, having set an aperture (again in half steps), the meter picks an EV value and selects a STEPLESS shutter speed to be used. It indicates this speed in the viewfinder in 1/2 EV increments. But, if you believe Pentax, it actually fires a stepless shutter value. The only way to check this would be with a strobe or a revolving object whose speed can be accurately set. I think getting down less than a 1/2 ev is good enough for my work.

That brings to mind the problem of light going into the back of the viewfinder and messing up a good shot. Since I always wear glasses becuase of astigmatism, I wonder if this does not mess up my shots even in manual mode. If you shoot in AE mode, the solution is simple. There is a shutter for the viewfinder. Perhaps this is the solution for me. Get the settings close - mainly selecting aperture for DOF - and then use AE with the viewfinder shut. Of course I have to do that before setting MLU because that locks the exposure. Any comments or more questions? This system is more sophisticated than I thought; but, that's got to be good.

-- Tom Goodrick (tgoodrick@earthlink.net), August 27, 1999

Answers

Tom, the solution to light entering the rear of the finder with the older version (Asahi 6x7 & P67)was to wear contacts and attach an eyecup to the finder. I have found that stray light entering the rear of the finder does not occur on many shots and therefore does not cause many lost shots due to incorrect exposure. But, who likes to lose any from this cause? SR

-- Steve Rasmussen (srasmuss@flash.net), August 27, 1999.

I tried the technique of using AE, setting the sun shade, setting MLU and then pressing the shutter. It is easy to do. I could also use the 12 sec delay if necessary. I have found the matrix metering mode works well in most cases. I think this is my solution. In most cases it should give nearly perfect exposure. However, I will also start using an incident light meter and using exposure compensation to crank in the exact AE settings.

-- Tom Goodrick (tgoodrick@earthlink.net), August 27, 1999.

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