I'm not sure if it will do it, but the official SD Card Format software might help link

Make sure that you copy off all that you wish to keep first.

I would expect that it is the responsibility of any repairer to weatherseal the camera in accordance with the manufacturers specification and that they would be liable for any leaks as a result of poor workmanship.

Pentax already have a lot of experience with waterproofing surveying instruments. So do Leica and Nikon. So it's not a completely new area.

A 300mm prime isn't as useful as a zoom and it's not as much use as a 500mm for birds etc. I've got both and the only drawback with the Sigma 150-500mm is the weight. IQ wise there isn't much between the two and with the high ISO of the K-5 the loss of a lens that has f/4 isn't such a big deal.

You might find a 55-300 more useful. My favorite small walkabout lens is the Tokina 80-400mm, but they are hard to find in Pentax fit and need decent light. Hopefully something similar will be released shortly.

I can't believe someone paid £975 yesterday on ebay for a battered Pentax SMC F* 300mm F4.5 ED (IF) link
I sold an almost mint one on here for just over £600

Very interesting and well executed shots. Looks like
a photographers paradise

That's true Your shots are also being reduced to 800mm by the forum software 800 wide is the preferred width, but if anyone wants to see them 900 wide clicking on them should open them in another tab.

I like the way they are driving the speedboat backwards
The lens look good and sharp at f/8 but the k-5 seems to struggle in bright sunlight. I'm not sure if these are from RAW or JPG, but you have the Contrast set to +2 which is too high for bright sunlight. I'm not sure if that effects the RAW files as well as JPGs.

Vericolor was a pro film and needed careful handling. Kodacolor on the other hand was an amateur film, designed to have a Xmas tree at each end.... i.e. It could be left in the camera for over a year

Yesterday I used the Sigma 150-500mm with the in lens SR on and I forgot to turn off the SR on the K-5..... so both SR systems were ON!

It doesn't seem to have caused any problems the shots are as sharp as they usually are

I doubt if they will cover 6x7? I've got a Schneider one that does 35mm, but no bigger. Mamiya did some good ones for 6x7. Here's a bit of a review link

A lot of loupe's only cover 35mm negs. Some do 6x7 but they are expensive.
The 5x magnifier off an old 6x6 camera should be OK.