Originally posted by Laurentiu Cristofor 'm not sure how well the FA would do for sports photography given that it has PF issues.
If you keep your expectations to realistic levels you would know by now that pretty much every fast (f/1.2~f/1.8) non-apochromatic lens designed for portraiture will suffer from purple fringing, the Leica-R summilux 80mm f/1.4 suffers from it, the Canon EF85mm f/1.2L suffers from it, the Nikkor 85mm f/1.4G suffers from it, the sigma 85mm f/1.4 also suffers from it and yes, the Pentax FA77 f/1.8 limited suffers from it
almost every modern lens below 100mm that is f/2 and faster will produce varying amounts of PF to some degree! the only lens that doesn't have a problem with purple fringing is the manual focusing Leica Summicron-R 90mm f/2 APO - which is a superlative lens, but also quite rare.
I personally wouldn't recommend the FA77 for sports photography, it is very slow to focus .The golden standard for screwdrive focusing is the FA*85mm f/1.4 which focuses
very quickly - but that lens has been discontinued for some time.