Originally posted by Digitalis a word of warning PF-U: focusing an f/1.2 lens isn't easy.it takes a lot of practice and experience. because the DOF that you see in the VF isn't anywhere near as shallow as what you're actually getting. Katz eye focus screens help, but they foul up the spot metering in some cameras - I personally don't use them for this reason. spot metering is too important for my wildlife photography
I'm considering myself on getting a Katz-Eye for the K-7. I have them in my previous SLR and dSLRs. they are of convenience. anyway, I haven't experienced any metering problem and I'm glad I didn't. I guess that problem is not that all prevalent to all cameras.
another asset in focusing would be the magnifying eyecup.
so far, the OME-53 eyepiece helps me at close-focus, wouldn't bother using it in the dark though. usually, I would switch to LV when the lighting is really bad and couldn't see and focus in the OVF anymore. although LV is very helpful as well especially when it comes to fine focusing the tiniest or smallest detail of the object by magnifying it as much as 10x manually or 6x AF. quite nice, eh? would had been much better if grid lines were present during magnification, not to mention the absence of the friendly focus beep/lock during manual focusing. due to this handicap, this would also mean that there isn't a catch-in focus shooting either for manual lenses during LV mode. the other downside of LV is that it's shaky and laggy view, most especially during image magnification, and also the slow AF. due to these weaknesses, it is essential to use this only with a tripod or still subjects. this is also the reason why a KatZ-Eye is still a necessity when shooting fast animate small/miniature subjects.