Consider the following, but do NOT attempt this one on your own.

Depending upon how close one lives to a good college and/or university, especially one with a good science department. Certain types of higher end (focusable) lasers are able to fix most fungus issues on a variety of lenses, even despite how many groups and elements there are.

Also, depending upon where one lives and IF there are such things as mostly sunny skies... Try burning it off with the sun and/or a magnifying glass of sorts

On a number of Pentax digital slr's one can also simply switch over to the live view feature to eliminate any movement caused by the mirror

Strongly weight the following; as can be found on quite the variety of policies throughout numerous countries of the world.

1. Does the insurance cover the item if it is (**ever**) used on a professional basis?
2. Homeowners insurance may very well not cover ones camera purchases IF the camera is used professionals.
3. If the camera equipment is in a vehicle, and the vehicle and contents (outside of people) are destroyed in an accident of no fault on oneself, then... It is not unusual to need both ones OWN car and or renters/owners property policy.
4. Even if equipment is covered under a homeowners policy; there are still considerable restrictions on that same policy such as... Never keeping a camera in a basement, attic, or certain other places.

I've tried the "original" Pentax K3 (most recent model run, although have not yet tried the K3 II in such extreme weather yet) in negative thirty degrees centigrade.

It did not effect the camera body adversely. Some of the lenses were effected, even some of the Pentax WR labeled lenses, yet all continued to work - although controls were starting to show reaction types of signs. SDM motors slowed down significantly, ironically screw drive lenses picked up their pace (??), more efforts to zoom lenses, and also use them in manual focusing.

Although I haven't checked for this link in a while... Anyone else happen to see both video and still pics of the K3 that went to the top of Everest? ...Or the two Pentax's that are at one of the Antartic bases?

On a few side notes... Pentax has a considerable edge on this one, and I'm frankly surprised it isn't used more to the companies advantage. That Pentax has better WR than almost all of the Nikons. More about the K3... Sincerely like the grip and rarely go without it; adds the secondary dedicated battery or off the shelf aa's. Still wish there was some version of a tethered cord for use in the field

Outside of price they are quite easily beatable

Pentax 560; photographs of horse taken from many, many meters away

Was on display (under glass) in NYC.

If one knows where to look on the internet, it was also witnessed (photographed, videoed, and also by at least two smartphones)... The Pentax full-frame was fully operational outside of the show in NYC, prototype stage perhaps, more like a Beta stage product, yet still fully functional

"Almost all of" the Manfrotto line sticks are compatible with their tripod heads. Could it be something in the head such as the screws and/or allen bolt/nuts?

I prefer the Gitzo series three carbon fiber, yet most of the higher end Manfrottos are also equally as impressive. Just be extra cautious of weight ratings, which are not quite standardized or tested well enough, and also be sure to routinely check and tighten connection points for Manfrottos

Current model EOS 5DS R; when running in full-frame is at just over 50mp, using aps-h still remains at over 30mp, and even when using aps-c still gets just under 20mp.

Even with that 20mp, it's better than any currently modeled Pentax non medium format. When the Canon is taken up to the full frame 50+mp, shall we compare it to Pentax medium format?

First new SLR was a Pentax K-1000. Was able to find an unused yet still used/not new Asahiflex I later that same year.

Some other memorable purchases from that "era"

One of my first cameras was a Ricoh, that was actually purchased at a trade show. Ironically the Ricoh and Pentax booths were directly beside each other. The reps from both booths were amusing themselves by switching out lenses between different cameras; Pentax to Ricoh, etc.. The Ricoh model purchased was a Ricoh XR-S will a small set of solar arrays on the pentaprism that somehow managed to both power and charge the entire camera.