This use of the Green button for stop-down metering seems to be the preferred method for most Pentax dslr owners using manual lenses.
Date models are also available.
Espio 90MC, tO BE done.
Heres an article covering MF technique.
However, I occasionally have to use the AE-L button in high contrast situations to get the desired exposure, especially with my M series lens.But thats just the way I roll.It will then offer up a shutter speed that represents a neutral exposure reading for the scene.One of the best things about kfc t20 cricket games shooting a modern Pentax dslr is having access to 35 years worth of wonderful K mount lenses- all with shake reduction!
Espio 928, espio 80.
Most of the info I have read says you will get the best results by using the shortest focal length setting for your lens.
While this dirk werner funktionalanalysis pdf works, I find it rather awkward to use as my shutter speed control has been re-mapped to the front E-Dial wheel.The main potential drawback is that the lens is always shot wide open- despite what the setting on the aperture ring may.So, if you do like I do and focus, recompose then shoot, you will likely get a different exposure when you recompose then you did when you set the focus.This can be especially frustrating when using fast lenses with extremely short depths of field while trying to achieve critical focus on a specific point of the subject.A good excuse to take lots of pictures :D.There are a number of nuances for different lens and camera combinations and countless permutations of old lenses, each with its own idiosyncorosies.Another benefit of doing this is that the focal length you input here will be recorded in your shot exif data- making it easier to tell which lens you were using later.In pattern metering mode with my A series lens I rarely find this to be a problem as the pattern metering seems pretty adept at figuring things out.