50mm @ F1.7

MX veteran
Posted 20/03/2008 - 15:58 Link
Having read on another thread that fast lenses have a poor resolution at the edges when wide open, I fished out my old 50mm and took a few at F1.7 to see what it performed like. This one is of my gravel drive and the cat IS MEANT TO BE OUT OF FOCUS, I just wanted the to demonstrate the lenses extreme lack of DOF at F1.7. I think the resolution at the edges is acceptable. What do you think?

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K100D Super, 18-55, 50-200, Sigma 10-20, Sigma 70mm macro and lots of old lenses
johnriley
Posted 20/03/2008 - 16:43 Link
Unfortunately not a good picture to test lens sharpness - the f1.7 aperture means that little of it is in acceptable focus.

Try a landscape shot at infinity or a newspaper closer up, but in the latter case make sure camera and subject are completely parrallel.
Best regards, John
iceblinker
Posted 20/03/2008 - 17:00 Link
There was a thread a few weeks ago that demonstrated the 50mm 1.4's softness or bloom at F1.4. It's enough to be quite disturbing, or quite attractive, depending on subject and taste.

It would be interesting to see how the 1.7 compares to the 1.4 at F1.7/1.8 and 2.0. I might have a go myself sometime.
~Pete
iceblinker
Posted 20/03/2008 - 17:17 Link
Quote:
Having read on another thread that fast lenses have a poor resolution at the edges when wide open, I fished out my old 50mm and took a few at F1.7 to see what it performed like. This one is of my gravel drive and the cat IS MEANT TO BE OUT OF FOCUS, I just wanted the to demonstrate the lenses extreme lack of DOF at F1.7. I think the resolution at the edges is acceptable. What do you think?
It's hard to judge because of the angle of the camera. The edges wouldn't be acceptable to me if they were supposed to be in focus.
~Pete

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