[glanglois]

Pentax can't, and won't take responsibility for how non Pentax equipment will operate, so they don't acknowledge the existence of no Pentax equipment in their literature.

Bingo!

[bwDraco]

My interpretation of the manual is that only auto-aperture capability is needed for multi-segment metering. This has nothing to do with the brand of the lens.

--DragonLord

[Lowell Goudge]

My interpretation of the manual is that only auto-aperture capability is needed for multi-segment metering. This has nothing to do with the brand of the lens.

--DragonLord

That is correct.

For all those who question whether they are getting matrix metering with Non Auto aperture lenses, there are a couple of simple tests you can try.

The center weighted metering will respond to a bright light located off the center of the screen, so using both matrix and center weighted settings, place a light against a uniform colored wall at half way between the center of the viewfinder and one edge. (note it is best to use a tripod for this to gaurantee framing does not change) You will find center weighted metering will tend to underexpose the wall and expose more correctly for the light, matrix metering will recognixe the bright spot and let it burn out a little, to get a better average exposure of the wall.

If there is no change between the greyscale value at the middle of the frame between the two shots you are in center ewighted mode, regardless of what the EXIF says or the mode switch is set to.

[FHPhotographer]

Well, it really depends on what "correct" means. If you mean that the camera works that way, the you and other posters are correct. However, if you mean that's what the manual states, then you and others are incorrect. But that's a fine point of debate because the camera works the way it should and the way the other posters say; my mistake was trusting the manual instead of trusting the camera.
Brian

That is correct.

For all those who question whether they are getting matrix metering with Non Auto aperture lenses, there are a couple of simple tests you can try.

The center weighted metering will respond to a bright light located off the center of the screen, so using both matrix and center weighted settings, place a light against a uniform colored wall at half way between the center of the viewfinder and one edge. (note it is best to use a tripod for this to gaurantee framing does not change) You will find center weighted metering will tend to underexpose the wall and expose more correctly for the light, matrix metering will recognixe the bright spot and let it burn out a little, to get a better average exposure of the wall.

If there is no change between the greyscale value at the middle of the frame between the two shots you are in center ewighted mode, regardless of what the EXIF says or the mode switch is set to.

[Wheatfield]

Brian, I hate to sound like a dork, but I'm really confused about what you are asking here.

[FHPhotographer]

wheatfield, the original question was whether or not the matrix metering mode worked on non-Pentax lenses or defaulted to center weighted. By reading the manual literally, I concluded it would not; however, as others pointed out, and I agree with now, any AF lens that fits can use matrix, at least on the K20. Again, the manual is very poorly written and suffers from even worse copy editing. One of my momma's sayings from her stubble-jumping childhood in Kayville, SK, was that "sometimes they hear but they no to do." Never quite sure what it meant, and it sounds better in Rumanian, but it still seems to loosely fit many occasions,
Brian