The Olympus OM-1 was the first smallest SLR with the largest VF at .92X magnification. Pentax topped it with the release of the MX with a smaller body, full info viewfinder (shutter and aperture) as well as a .97X magnification and a choice of 8 screens.
Originally Posted by Markster
As a point of comparison the Canon AE-1 has an .83X magnification VF which is typical of most all other cameras.
The Pentax MX was their pro camera at the time of release and was superseded by the LX which has most shutter speeds available when battery is exhausted after the Nikon FM3A which has all. Both have aperture priority exposure when battery is good.
Although the LX did not keep that great large viewfinder of the MX, it has the widest exposure accuracy range of any camera todate - down to - 6.5 EV (125 sec at f1.2) to EV 20 (1/2000 sec). Along with that it constantly monitors the scene while the shutter is open and varies the exposure time accordingly. So not only can it make an accurate very long exposure, it will shorten or lengthen it if the scene lighting changes. Cover the lens of the AE-1 and it will max out at 30seconds. Shine a light on it and it will continue to keep the shutter open based on the exposure calculated at the time the shutter was activated. Must be a Canon thing as even my EOS-1V acts this way too. The Olympus OM-4T acts like the LX and although it's exposure range is not as wide as the LX, it is still wider than most and has spot metering that the LX does not.
Yeah I say widen your exposure range and explore different bodies . . . ;-)