Con
Medium format is a compromise between small format film and large format film
Must wait until film is processed in order to see and evaluate image
Cost of film processing
Does not have automatic/electronic features
Digital cameras have just about made film cameras obsolete
Parallax problem when using close-up supplemental lens
Not good for macrophotography
Not good for extreme wide-angle shots
Not good for telephoto shots
Not good for head & shoulders or head shot portraits.
Depth of field not visible in viewfinder
Filter effect not visible in viewfinder
Hard to change film in the middle of a roll
Multiple exposures are not possible (except with interrupted timed exposures)
Lens is not interchangeable.
Not available in telephoto version
Possible to forget to remove lens cap
No built-in light meter
No provision for motor drive
It is hard to read exposure settings when the camera is mounted on a tall tripod.
Slow to operate
Requires tripod for best results
No built-in spirit level for vertical (portrait orientation) shots
If you use the 690 to take photographs that include the sky, at f/5.6 you will definitely notice vignetting
Super-imposed image rangefinder makes focusing difficult for me
Focusing is difficult due to small size of rangefinder
Lens and lens hood block one corner of the viewfinder
No self-timer
Shot counter influences shooter to shot conservatively
Shutter release cable attaches to top but not front shutter release button
Airport security usually wants to see what is inside this over-sized camera.
https://flic.kr/p/doX6jQ