If the thing is sitting right on the sensor, and presumably simply casting a shadow on to it, from zero distance or thereabouts, why does the aperture affect it?

I see no way that this can be true.

Pentax publishes this moderately interesting document.

In it, it says this:

[quote="Pentax"]How does the SR system control hand shake?
By calculating a correction value from the amount of shake detected through the gyro sensor, the system shifts the image sensor at high speed, by magnetic force, to vertically or horizontally compensate for the shake.[/quote]I understand this to mean that it derives its action solely from movements of the camera, not also of the subject.

[quote="
golfdiesel"]The user manual of the K20D mentions that you should turn SR off when shooting fast moving subjects[/quote]I can believe that the camera might interpret intentional camera movement (especially if not smooth) as shake, and correct for it.

That document also says this:

I find this annoyingly obfuscatory. What does "appropriately" mean here? Does it mean too much, the wrong sort, or not enough?

And with panning shots, where does this 'camera shake more than by hand' come from?

They're either trying to deliberately hide things, or they've just dumbed it down, creating the illusion of explanation, but not really making anything much clearer.

Is it always in the same place? If so, then I think it has to be something on the sensor.

I've also found that muck on the sensor doesn't appear in all the shots, even when the background is neutral enough to think that it should be obvious. It shows, then not, and then it appears again.

I don't really understand this either.

You laugh, but I kid you not, I had something nearly that big on the sensor.

There was this heowwwwwwwge thing on a few of the photos, and I gave the innards a blast with the rocket.

And a great lump of something, easily big enough to see, fell out. Not floated out, fell out.

How it got in, heaven knows.

"If your name isn't Don, leave it on"

Well I've got IE7, Firefox 2 & 3, Opera and Safari in current use, since I often need to check that web sites work Ok on more than one browser.

Opera and Safari are very nice, but for doing real work, and all-round flexibility, I think Firefox wins out, largely because of the range of extensions.

PicLens, AdBlock, FlashBlock, FireBug, FireShot are the ones I use most.

I'm editing this with Safari - and seeing all those ads again is a bit of a shock

I think so. eBay selling prices are very unpredictable, though.

This one went for £84 recently, which I'd have said is a bit on the low side, but it may be that the fact that the DA 55-300 is now available makes all the existing lenses of that range (eg 75-300, 80-320) a bit less desirable.

My guess is that now that the Pentax range of new lenses is so much more complete than it was this time last year, the enormous price inflation in A-series and later lenses that we saw this time last year is over.

Here.

Gallery | Competitions, from the header menu.

You're probably right.

It's a bit naff to have to do this though, isn't it?

To replace a picture I post on a thread, hosted say in PhotoBucket, I have to

- delete that picture
- upload the new one with another of exactly the same name.

, otherwise, because I can't edit the post, the link will be broken.

Say I've got the original picture linked elsewhere - if I change it in the host, that forces it to change wherever else I have the original linked, which I might not want to do.

All this restriction, because in their wisdom, the site owners have decided that we need to be protected from evil trolls bent on mischief. Of which, we're all agreed, there currently are none.

Why can't we just have our edit facility back for now, so that we don't have to jump through complicated hoops, in order to do the simplest things?

And then if, one day, this place becomes an anarchic, troll-ridden place where threads are being changed willy-nilly, just take it away again.

It does seem a perfectly reasonable compromise to me - no restriction while there is no problem, and then re-introduce it if in the future there is.