I've had mixed results with the Pentax K3 while set on the continual autofocus setting.

I've found that the CF setting works best with better aperture lenses and also preferably not SDM lenses. So what lenses does this leave exactly?

One of the best CF lenses that I've ever used on an interchangeable camera of any sort (with the exception of 4/3 sensors) is the Sigma 300 f2.8... I've used it with a Porsche 918 coming basically directly at me at full speed. Both the camera and the lens were able to keep up with the vehicle in less than ideal lighting, even when the car was beyond the close point of being full framed into the viewfinder.

Have found that most of the Pentax FA's work well in the CF setting, with the most definite exception of the FA macros. Also any of the Sigma EX DG series, as long as they also retain the above average starting apertures.

Other camera settings to consider... For some unknown reason the Pentax K3 also works best for continuous focus photographs while also set in the narrowest focusing (basically spot focusing) and also spot metering - better even if one can either lock in the metering setting or go full manual except for focus,

In a variety of places all throughout the world...

One can have law enforcement and/or the courts seize work that someone is using without your permission. Yet it gets better. Even seize internet accounts, computer hardware, even nearly full property seizures

IF that version of the Pentax lens IS repairable - then it typically would cost about 1/3 of the price of replacing the lens with a new one. As for the time factor involved in repair, wishing that I knew how recent of a lens run this one is.

But for moving planes which fill a reasonable portion of the frame - even the entire amount of the frame... Why not just lock the focus and also use debt of field. The planes are always far enough away when they are moving that one would never need anything close than the infinity setting

Two NYC mega-sellers, and also retail locations throughout Asia have stated the same exact thing. They know of release dates at least six to nine months in advance. Nothing has shown that ANY Pentax full-frame will be making release this year.

In the meantime, watch as Canon, Nikon, (even) Sony continue to steam roll forward; sensors that are 50+ mp and very soon they'll have their "entry level" full-frames that will cost not much more than a Pentax cropped sensor

Take a look at the present and very near future; items such as the Canon EOS 5D R, at 50+mp... At two camera stores in america it's already pre-sold over one thousand copies.

It should be even more interesting to see what type of price point Pentax comes up with. Guaranteed it won't be anywhere near the price point of Canon's "entry level" price point full-frame

Until Pentax full-frame comes around possibly within about six months...

I am one of those people. There are a lot of lenses out there that are not currently in PK of which are even available in camera mounts even for Sony ?!? Take a look at that Sigma line availability, especially for macro; Sigma could easily add in 10++ lenses in PK. How about Zeiss? While most Zeiss isn't exactly the most current, it is incredibly difficult to match optically - yet no current new releases for Zeiss in PK. The same could be said for items such as bellows, etc...

Whatever you might be willing to part with or have an interest in selling. "Unfortunately" this would not be for me, I would perhaps eventually be shipping it over to a Carnegie Mellon University instructor a bit across the pond.

Could or would you be interested in selling some or all?

Very well documented.

I've also been instructed to pass along a message to MattMatic... If you still have those parts, would you be willing to part with them?

I would not mind having that Pentax label on one as well. But... I got a verbal statement from one of many Pentax people not all that long ago on their existing and planned future releases... Rephrasing briefly from what was stated...

That Pentax owners were interested in compact lenses, and WR. They almost ran with the idea of many variations of what you also referred to as constant aperture lens, particularly in that range. They compared their label with that of the existing Sigma 24-70 (constant aperture) f2.8 and others... They quite clearly stated that "they" couldn't do it for anywhere near that price, size, and weight - emphasis on price.