When it rains, it pours -- we knew Pentax was due for new interchangeable lens cameras, but it just surprised us by unveiling three of them at once. The mid-range K-50 and entry K-500 DSLRs at the front of the pack represent slight upgrades to the 16-megapixel K-30 on the inside, with both gaining a higher ISO 51,200 sensitivity and Eye-Fi card support. They mostly differ on the outside. The K-50 keeps the K-30's weather sealing, lithium batteries and extreme c
