Well it does seem that some are getting the problems and some are not.

Do you have any A- series lenses? If so, I'd be interested to see a comparison between the following situations:

1. Camera in Manual, aperture set using aperture ring, exposure chosen by camera using green button stop-down metering.

2. Camera in Manual, lens in A-mode, apertures set from camera, exposures set for correct exposure using green button.

Obviously, camera on tripod, viewfinder covered up for the metering, lighting conditions consistent.

My experience with several different A-series lenses is that the results in each case are not the same; the A-mode exposures come out right, and follow the law of reciprocity as the aperture is gradually reduced. With stop down metering, reciprocity does not apply, and the exposures are often wrong.

I haven't yet posted the results of the tests I've done since applying the 1.11 firmware update, but it's still not right on my camera.

I'm planning to repeat my tests over the weekend with it; I'll report back.

Hey, in the interests of scientific accuracy, I was ranting, not whinging.

If only I were...

Well I have tried all the available metering modes.

But I don't see the point of the experiment you suggest with different lenses of the same focal length - as you say, lenses have their differences. Please tell me what I'm missing here..

My point is that for a given lens (I have only two M series lenses, but I've done this with a couple of As in non-A mode too), ordinary reciprocity does not seem to hold. Stopping the lens down a stop at a time - and then pressing the green button for it to take a peek while stopped down - does not seem to result in the camera picking anything like the exposure that you'd expect.

And specifically with the A lenses, it is possible to compare the exposure the camera picks (in manual mode and stopped down) in non-A mode, with the exposure it (still in Manual) picks in A mode, with the same aperture selected on the camera. In A mode, everything is fine and what you'd expect in the way of reciprocity.

It's a valid thought.

But from my first post on this thread:

I'll run the tests again I think. I'm starting to doubt my own name....

But I'll happily eat a Desperate Dan-sized slice of humble pie if this all turns out to be finger trouble...

Well I suppose it's understandable that if you've prejudged me as a whinger, you aren't that interested in reading the example I've posted, but let me draw your attention to it.

https://www.pentaxuser.com/forum/viewtopic.php?t=3867

Post number 6.

I'd be the first to accept that I might be doing something wrong, and the most pleased if it turned out to be so.

This is true.

But have you also done this with an A lens, first in non-A mode as above, and then cross checked the exposure/aperture combination that the camera says is correctly exposed, with the exposure it chooses for the same aperture (selected with the rear e-dial) with the lens in A mode? All with the camera in Manual.

My experience is that they are not the same.

And if they're different, they can't both be right.

Hmm. Very different from my experiences. Maybe not all K10Ds are the same?

I've heard this argument before, and I think it's something of a red herring.

I've taken some night time shots now in automatic mode, where the exposure it's calculated is 30 seconds (sic). There can't be much light hitting the meter, even though the lens is wide open when it's doing it, and the shots have been beautifully exposed.

So unless there's something very different going on with stopped-down metering, I can't believe the "insufficient light" argument holds any water at all - except in exceptionally dark conditions, in which case all bets would be off anyway.

Agreed. I have just two pre-A lenses - the M-series 135 F3.5 and 200 F4. With the kit 18-55 DA, your 75-300 FAJ and then various A lenses from 28 up to 400, I'm pretty well sorted.

However, it's not just the two primes that are a pain to use in stop-down mode. Sticking anything between the lens and the camera, for instance a teleconverter or an extension tube straight away makes it into a manual lens, with all the metering issues we've been talking about. So I now have to think about replacing my other non-auto accessories.

Are you referring to the "Notes on using aperture ring" on p210 where they talk about the restrictions with using the aperture ring.

This reference to exposure errors is in relation to aperture priority mode, not manual.

Under manual mode (all lenses), it just says "exposure check is possible", with no reference to metering errors.

And I'd restate the point I made earlier, namely that it's clear they intended it to work, otherwise they'd never have bothered to use the green button to stop the lens down and set the exposure at all.

Yes, we can't expect complete backwards compatibility for ever, but the vagueness in the manual, taken with the clear intended behaviour just smacks of a cock-up.

And although I agree with all those that have eulogised the camera with A and post-A lenses (and I still don't regret buying it), it has that whiff of spoiling the ship for a ha'p'orth of tar about it. Which for a company that seems poised to make something of a return from the doldrums (if you'll forgive another nautical metaphor), just seems a shame.

Or even meter in one of the non-manual modes, and do the math to work out what the exposure should be at whatever aperture you want.

Of course there are work-arounds, but it's just not acceptable in 2007 to have to work around such a fundamental problem as the camera's metering sytem simply not working right - and the weaselly-worded ambiguities in the K10D manual don't let Pentax off the hook, AFAIC.

Anyway, just to muddy the waters still further, there seems to be evidence that the problem doesn't affect all K10Ds.

http://www.pentaxforums.com/forums/pentax-dslr-discussion/3188-k-m-lenses-manual...

... for instance, has a couple of guys reporting no problems.

Is there anyone here with a K10D that's done some careful measurements and found that their camera is getting the exposure right?

Exactly.

Kinda puts into perspective the now rather hollow-sounding, arm waving comments from the whingers who bang on and on and on and on about how unjustifiable it is that C/N are in the ascendant while Pentax historically have been in the relative doldrums.

It's all the salesmen's fault, of course... why wouldn't we be over the moon about this groovy slimming 'let's digitally stretch the picture, yes the punters will think that's cool' function instead of a metering system that ****ing works?

Sorry. Do I sound like I'm ranting?