Originally posted by bull drinkwater don't know what you mean by dead end. with all the 564 lenses and the 67 lenses with adapters any owner is in good shape. thereare plenty of auto focus in the 645 line and manual focus with the rest has not been a problem for me.i have 2x and 1.4x teleconverters and a screw on wide angle for my 45mm that acts as a fisheye. when i want a really wide shot i use the 45mm and pan 3-5 shots.if it's a far away scene i use my 200mm and pan 5-9 shots. so much to do with this camera and the lenses availiable.
By dead end i mean pentax not developing and evolving the system further. Kind of like the pentax 6x7.
Also, there are only 3 modern lenses for the 654D, and while some of the old glass is sharp, there is more to a modern lens than sharpness. I have a few older lenses I use on the 645D but they don't have the same look and contrast as the modern ones do. They also lack weather sealing which for what and where I shoot is important.
A camera system should be a long term investment and that means a healthy lens lineup and a 3rd party ecosystem around the camera. With a big paradigm shift going on at this moment (no mirror box and smaller size), will pentax keep producing 645D lenses or go after building a new medium format system that is more like the mamiya 7II that has a host of much smaller lenses ? If it will, great, but at that point investing more money into the 645D form factor would be silly and a waste of money unless this form factor can have unique advantages going into the future.