Had me before a mirror 500 Tele (Vivitar) was bought and with respect. Focus totally disappointed. Quite different here: focusing even work directly in the viewfinder without magnifier and without using LifeView and magnification. Simultaneously, the first test images with my Pentax K-500 (without a tripod!) Convinced in contrast and sharpness. On the manual dimming and opening the shutter to focus you have to get used to, but that's quickly into flesh and blood. Certainly one can - if one enlarges the images strongly - Discover blurring at the edge and at full aperture CA, but the price-quality ratio is unbeatable!
