I don't really see what you're driving at I'm afraid.

I'm not concerned with the aperture priority results in A mode at all - just whether stop-down metering (in manual mode) gives exposures that are close to what you'd get by metering wide open, and then doubling the resulting exposure for each stop away from that wide open aperture you want to shoot at.

On the K10D it doesn't, by a country mile. On the K-5 it does, more or less.

Given that half a stop either way is very rarely enormously important (unless that half stop happens to burn out the brights), it's clearly good enough for K and M lenses - set the lens at the aperture you want, leave the camera in manual, and just before you take the picture, press the green button to set the exposure.

I forgot to say, by the way, in my OP, I took all sets of readings at ISO 200. I didn't try it at higher sensitivities.

Finally got around to putting the K-5 on a tripod and writing down the metering under reasonably consistent lighting with a couple of lenses.

In summary, the K-5 stop-down metering is much, much better than the K10D's.

It doesn't quite follow the arithmetically flawless reciprocity you get in A mode, setting the aperture from the body, but it's not far off.

If you're interested in the numbers, here they are:

[IMG]http://i162.photobucket.com/albums/t244/chris5gd/Technical/StopDownMetering-K5-2011-10-01_1439.png[/IMG]

At first glance it looks like the stop-down results for the 28-200 are about a stop wrong all the way down, but I think this is probably due to the fact that the marked apertures are really about a stop slower as you approach the long end. So the right hand column needs to move down one place really - which makes the exposures much more consistent with A mode.

The camera was on a tripod, and I had my eye jammed up against the viewfinder (I didn't bother with the viewfinder cover). I ran through them as quickly as possible, and there's no cloud today so I think the lighting was pretty consistent.

It looks to me as if stop-down mode is good to about half a stop, on this showing.

K and M lenses are usable again!

You need to allow shutter release for 'aperture not set to A' in the custom settings.

This is the second most frequently asked question here, after "is there something wrong with my camera, I can hear something moving inside"

Welcome!

Very true, but you do get the odd one.

My dad had a little Braun gun, he'd used it for years on his Super A, and he'd just got his K10D.

I stopped him putting it on till I'd measured it, and there was over 200V across the contacts. I don't know whether that would blow up a Pentax dSLR but I don't think I'd chance it.

It b***dy hurt too, when the probe slipped and I managed to touch the pins.

I think it's wise to be wary if you have an old non-Pentax gun lying around.

It did indeed.

I then put another card in, with image numbers lower than the one it had reset itself to, and took a picture... it did not reset itself again, but continued counting at the correct shutter count.

I then copied an old DNG on to the card, having renamed it to the number that the camera would next expect.

Sure enough, the next picture was one more than that.

However, now the numbering was ahead of the shutter count. So when I deleted the bogus image, and renamed the remaining one to the shutter count as above, the numbering did not reset.

To achieve this, I had to reset the numbering to 1 again, take a picture (now numbered 1), and rename it to the shutter count as Mike suggested.

This worked again, so now my numbering is correct!


So the rule appears to be:

- If the image number on the card is GREATER than (or equals) the number the camera's expecting to use, the one on the card overrides the saved sequence and the camera starts counting at one more than the one on the card.

- If the image number on the card is LESS than the number the camera's expecting to use, the card is ignored and the camera's saved value takes precedence.


Gonna quit now, while I'm ahead. Thanks Mike

Awww...

You guys are truly inspirational.

I'll try a couple of things over coffee in the morning and report back.

I did somehow suspect that even the legendary combined wisdom of this forum might struggle a bit with this one. I lose the will to live even contemplating investigating it further, so I probably won't.

Still, I like to keep you lot on your toes with candidates for the 'most unanswerable question of the week' award....

Ok, so I wanted to have the image numbering on my new K-5 match the shutter count as closely as I could, so when I got it home, I carefully proceeded as follows:

- went to 'Memory', and switched off the saving of File No.
- went to 'File name', and did a reset.
- went back to 'Memory', and switched the saving of File No. back on.

Sure enough, the file numbering started at IMGP0001, and continued thus across several SD cards.

Then, there came a point where I had to grab a shot quickly when the card was full, and I happened to put in a card that already had a load of old pictures on it from the K10D. To my extreme annoyance, the numbering then started from IMGP9940 or something, and continued from there.

So it seemed that numbering on the card had somehow overridden the saved sequence that the camera was supposed to be using.

Stupidly, it didn't occur to me to delete just a few earlier images on the card with the correct numbering, to make some space, and put it back in to attempt to switch back. So I reset the numbering at 1 again as before (muppet).

In any case, repeating the experiment with another different SD card has not given the same result - it started counting at the latest number plus one (which is should have done the first time), not the highest number on the card plus one.

The net result is that I'm now completely confused... and the following possibilities occur:

- the image numbering was affected by the fact that the ones already on the card the first time were K10D PEFs

- the restart was due to the fact that the numbering on the images on the card were much higher than on the K-5 (9000 odd, rather than a few hundred)

- I've done something completely wrong.


Any ideas (other than 'put the camera down, and leave it alone')? I'd quite like to have my image numbers reasonably 'right' but I'm quite likely to do whatever I did wrong, again, unless I can find out what it was.

A bit of a convoluted question for a Friday afternoon, sorry.

Also, most of the pictures in this album were taken with the Sigma 10-20.

Not all at 10mm, but I really like the lens out and about. I was in Edinburgh the other day, and had only the 18-135. It was extremely frustrating not to be able to go wider.

Sigma 10-20 F4-5.6

10mm (about 12 feet from the wall):

[IMG]http://i162.photobucket.com/albums/t244/chris5gd/Technical/IMGP0271.jpg[/IMG]

Note the pronounced barrel distortion at 10mm. It's all gone by 12mm, though, and it's easy to get rid of on the computer.

17mm, same distance.

[IMG]http://i162.photobucket.com/albums/t244/chris5gd/Technical/IMGP0272.jpg[/IMG]

10mm:

[IMG]http://i162.photobucket.com/albums/t244/chris5gd/Technical/IMGP0274.jpg[/IMG]

17mm:
[IMG]http://i162.photobucket.com/albums/t244/chris5gd/Technical/IMGP0275.jpg[/IMG]


Bottom line: 10mm is *much* wider than 17.