My Tests And Evaluation On The FE24-240 OSS Lens

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So although I've already got 2 great primes to cover the average focal lengths and a wonderful 70-200G f4 to cover my long end, I wanted to consider a "walk around" zoom and had NO desire to keep a 24-70 f4 Zeiss I tried. I wanted MORE versatility in a  walk around utility lens. So I tried one and didn't care for the sides or corner sharpness. Today I got 2 new samples to try and see if either was going to change my mind as I still wanted a does all lens. One came in the morning so I ran it through it's paces. Sadly it was quickly apparent it had decentering issues as the sides were horrid and it didn't focus reliably either especially at the long end.

 

The 2nd lens came in the early afternoon and I began running it through it's same paces. I quickly found it to be highly competent for the 24-70mm range as it could render a sharp image at all corners stopped down to either F8 or F11 depending how far I went out. However I was still noting 240mm lacking in sharpness or IN depth of field performance at f11 or even f16. So I set out to test at what points the corner sharpness diminished.I tried out 136mm, 163mm and 191mm as the barrel allowed me to get close to the lengths I wanted to test out. In the end what I found was that at 136mm f11 the image was sharp shooting a distant target from one side to the other very nicely, no limitations here. At 163mm it was right on the edge of still being perfect but no further stopped down or not. So ideally using the lens from 24-160mm is ideal if you want to see sharp corners and sides at 100% view of the image on screen. 191mm of course illustrated the restrictions of getting a sharp image about 70% but not the extreme sides or corners. I also found f14 to be the limit before anything negative occurred in sharpness. If one understands the strengths and weaknesses of this lens it can be advantageous. If you are printing at or below 13x19 or not cropping off of a corner frankly you could easily get away with using the full 240mm at f11 and print it nicely. If you want to see the samples they are full size over at another forum that accepted large downloads

 

http://www.dpreview.com/forums/post/57213300