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Old Oct 9, 2010, 3:24 AM   #11
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Regarding the 50/1.4 vs 50/1.7 issue, here's an interesting comparison of an A 1.4 and F 1.7 (amongst other assorted 50s):


These tests seem to confirm that the 1.4 loses sharpness (but not resolution) wide open, but it certainly more than makes up for it at all other apertures. (Don't sell it, mtngal!)

My own experience of the M 50/1.7 is that it works best from f4 to f8, so that's where I usually keep it.
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Old Oct 9, 2010, 10:44 AM   #12
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Here's a thread I posted several years ago when I was seriously thinking of selling one of my 50mm lenses ( http://forums.steves-digicams.com/pe...mparisons.html ). The first ones will convince you that there's not a huge difference between the lenses, though I was using 2 cameras with different pixel count. The last two shots, the only ones I posted with both lenses wide open. As far as I'm concerned, my M 1.4 is not useable at 1.4. The 1.7 is still sharp so would be my choice when used wide open.

One of the things I love about these old fast 50 lenses is that you can do just about everything in the dark without looking. You can mount them by feel, using the bump on the lens to line up with the release button on the camera. You can shoot wide open by moving the aperture ring to the point where it ends. That's really handy if I want to catch a quick shot in the dark or an early sunrise shot. If you use the 1.4 you'd have to find wide open then click a couple of times to stop down, counting. Too much bother for a quick shot.

The thread I referenced was posted in 2006, and I still haven't sold the 1.4. I do find it useful when reversed in front of another lens for macros (though I haven't done any macro for quite a while).
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Old Oct 9, 2010, 1:03 PM   #13
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Originally Posted by a200user View Post
Thank you Jack!
That link is most helpful.

You're most welcome Jim, I note you have the K100D also ... there is an exposure setting technique for manual lenses in full manual mode I use on my K100D (not sure if it's mentioned in the previous link) If you operate the DOF preview on the On/Off switch, and observe the EV setting in the viewfinder you'll find the thumbwheel will set the exposure appropriate to whatever aperture you've preset, this is indicated in the viewfinder when you see 0.0 EV displayed. I feel sure this should also be possible on the K20D also. ... Jack.
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