The wheels work by using what's called a quadrature encoder. When the contacts go intermittent you get the behaviour you described.

Since the K7 is weatherproofed it shouldn't be dust or dirt in the wheel contacts... so I'd return it under warranty

Matt

Billy,
Check the full EXIF data on your shots.

Whether you believe it or not the EXIF definitely shows that the AE-L was engaged for the white-out shot. It may not be the whole explanation, but it's the most obvious thing I can see from the EXIF.

I think you'll find there are plenty of K7 & K5 that do not have this problem (as evidenced on this forum). The trick, though, is systematically working through the problem in a scientific and repeatable way.

Check the EXIF on your shots with: http://www.photome.de/

Matt

You should do a check with an evenly lit subject - say a cream wall.
Check with all your lenses and the camera on a tripod.

Vary the lighting (but keeping it evenly lit) should adjust the exposure correctly across all lenses. Though, as I said, some lenses can for some reason produce slightly off exposures compared to DA lenses. (Maybe it's some kind of colouration, or refraction - who knows!)

If you are checking real-world situations, the LV values are "Light Values". http://en.wikipedia.org/wiki/Light_value
PhotoME will show the pattern metering and the corresponding LV values - it's helpful in working out what's going on

There's usually an explanation to such issues - it's the process of finding out the source of the issue in a scientific and repeatable way that's the interesting part

Matt

SRS Microsystems have a reasonable stock of nice second hand lenses. Chris sometimes posts lists of special price S/H gear too

Matt

Well, if I were you I'd at least upgrade to K5 v1.03 firmware

If it happens in 1.03 as well, then I'll definitely have a look next time it occurs. Also worth checking out if anything else gets it out of that mode - for example, did you find that subsequent shots were overexposed and that only a power off worked?

Matt

Try with a different lens first
And try with pattern metering as well

I find the FA50/1.4 tends to overexpose slightly, so there may well be something that's lens-related.

Definitely worth checking out the full EXIF data with PhotoME - which will show the LV values of the metering

Matt

Okay dokay...

DR_O4030 = Centre Weighted metering, no AE-L. 11.1LV

DR_O4031 = Centre Weighted metering, AE-L enabled. 14.8LV. The exposure information doesn't tie up with the scene - so I suspect you pointed at a brighter area by mistake and pressed the AE-L button

Both had -0.3EV compensation too.

For macro shots, especially snow-drops, I'd definitely recommend fully Manual mode and make use of the shadow/highlight warning on the preview
White flowers can be a pain - it depends what you're trying to capture, and the specular highlights can cause all kinds of havoc for auto-metering on any camera.


DR_O3852 & DR_O3867:
These both show the same exposure matrix information (within 0.2 LV)
Pattern metering was used.

The only interesting difference is this:

* The overexposed image shows "Number of bits per component 16"
* The normal image shows "Number of bits per component 14"

The other two images both show "14" as the number of bits.
The overexposure looks consistent with a mismatch in the number of bits.

I'm not sure if there are any K5 custom settings for bit depth of RAW? Or whether this was a temporary blip that was reset with a power-cycle (as you mentioned).


Do also check what Custom Options you have enabled. There is one that supposedly links AE and AF points together. I thought this sounded a good idea. However, when I tried this it resorted back to effectively spot-metering in the selected AF point...

Hope this helps
Matt

AFAIK, the K7 & K5 have colour temperature adjustment for the phase focus.
For me the K20D would miss focus in low level tungsten light. The K7 seems absolutely fine.

Might be worth bearing in mind that when doing your low-light tests. Try with both tungsten & halogen if possible, or even with dusk outside.

Matt

(This reminds me of one of the Two Ronnies sketches )
...or is that the two Rommies

Mo problem
Matt

Shall I post you a mew M key too?