DrewE

What firmware revision do you have in the cameras?  I know support for HSM (and similar) in-lens motors was added in one version of the K10D firmware; perhaps upgrading to the latest if they're not...

So far as I know, that lens is optically identical to the DA40, only having different external packaging. If they're different optical designs, they're all but indistinguishable in terms of...

Of the lenses you listed, I think the 28-75 would be the handiest and best for the sorts of situations you're describing.  I may be misunderstanding what sort of things you're interested in using...

Did the AF/MF mode lever next to the lens mount get bumped/switched?  That's the only thing I can think of that you didn't specifically list as being checked.

All three are perfectly usable cameras for most things.  You wouldn't go wrong with any of them. The K-30 and K-5 are noticeably better at low-light shots.  The K-5, at lest, would be a bit more...

As was mentioned, the brand of SD card has no effect whatsoever on the image quality of your photographs—only how quickly the camera will respond (because of read/write speed) and, if the card...

Are you taking the cruise largely for photography, or is your photography more incidental to generally having a good time?  Do you have an shore excursions planned that would have special...

If it's in the cans, it's not "gently-used"; no, that's the "perfectly-aged vintage" paint. :-P

.MOV (like .AVI) is the container format; a number of actual video and audio codecs may be used inside these files in both cases. The K5 saves movies using the MJPEG codec, which means each video...

Congratulations!  (Unless this is just a one-liner joke...in which case, *chuckle*)

It sounds like the data pins are not making proper contact, or the aperture ring on the lens isn't seating well in the 'A' position.  I don't see any general reason why a lens that is compatible...

I like my DA40 limited a lot; the XS40 is, from all appearances, identical optically.  There are quite a few fine lenses in the 35-50ish range.  Arguably, the Pentax 55mm has the best performance...

More than likely, you had an image already on the card with a filename that the camera recognized as being number 538.  It will (by default, at least) skip numbers if there are already higher...

Assuming you have clearance to the lens for the inner filter (which seems very probable), I don't know why this plan would not work from a mechanical point of view.  There are about eight or so...

If anything, a time-lapse sequence would be less sensitive to lens speed than many other sorts of photography.  You're already using a tripod or other camera support, so (relatively) long shutter...

I think you might be misunderstanding what "focus lock" really refers to.  The camera doesn't physically lock the focusing mechanism on any lens; the lock refers instead to the sensors having...

It is dependent on the (actual) focal length of the lens, and you can tell the camera what that is in a menu setting.  If you turn the camera on with a non-chipped lens attached, it will...

What's driving the desire to upgrade the body?  Are you finding yourself running into limitations with your current camera, or wishing it were more capable somehow?  If you're thinking of upgrading...

Here's an idea...perhaps it's overkill, but these are relatively inexpensive and quite sturdy, although on the heavy side.  End caps would take a bit of creativity or craftiness.  (Other diameters...

I don't know for sure that they are identical designs optically, and don't mean to claim so with absolute certainty.  The information I've seen, however, does suggest that they are the same design...