Excellent, hope it works well for you.

They do crop up on here and on eBay from time to time. Happy Searching!

There are matching Pentax teleconverters from the M series era. The one optimised for your lens is the Rear Converter K T6-2X.

Some 85mm lenses and the Pentax 120mm lenses were made that way, so they could be used as portrait lenses wide open and yet were crisp when stopped down. Then the mood changed and lenses sharp at all apertures were the new paradigm.

In a way, yes, assuming the subject isn't a flat one. If it's flat, then it's all at the same distance so that would be in focus completely at any aperture. If it has depth (more usual) the as you stop down to smaller apertures more of the subject will be sharp.

Most lenses have distances marked on them, so focus on something and read off the distance on the lens.

The second part is called depth of field. At a given distance there will be things in focus in front of and behind where you have focused. A large aperture (small f number) will have very shallow DOF, for example throwing a background out of focus to make it less obtrusive. A small aperture (large F number) will have much more in focus as it will show increased DOF.

Hoping the pedantic amongst us don't want to confuse you, telephoto lenses have shallower DOF than wide angle lenses.

There are DOF tables, but the best way to get an idea is to shoot lots of images at different distances and apertures. then see what the effect is.

Hope that helps for starters!

I menu is a menu, by and large I don't see what difference it makes as long as we're used to it?

Just leave it on all the time - the setting is in the menus so far too messy switching it on and off. You'd miss too many shots.

You can add the viewfinder to the GR, it fits into the hotshoe. Crystal clear and one of the best I've seen. Very similar to the Q viewfinder, which makes the Q another candidate, with a choice of lenses.

When these cameras are thus kitted out they end up looking very much like the classic 1940s/1950s Leica rangefinder style of photography. In terms of function that is, but with faster AF knocking spots off traditional rangefinder focusing. You could be a modern version of the classic photojournalist.

Paulyrichard is on here, I'm amazed you haven't seen his pictures. Worth checking out.

The GR is ideal for this sort of thing, fast and sharp.

Getting in close and shooting candids is the forte of paulyrichard, definitely worth looking at what he produces.