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Nifty fifty STM - focus issues, or human error?

Started Nov 16, 2017 | Discussions thread
47872Mike Regular Member • Posts: 222
Re: Nifty fifty STM - focus issues, or human error?

I've just been testing my new 50 STM and am struggling  with the same issues. 
I tend to think it is not down to mechanical play since switching to live view nails focus every time, and using old-fashioned SLR AF nails focus on average a bit less than every other time, depending on light level (based on preliminary tests). Either that or the way the algorithm works excites the mechanical play and leads to the way focus doesn't come to rest at the same point each time you half press. 
My tests were done at maximum aperture but I didn't notice an improvement when I tried a few with the lens stopped down after reading some comments here (other than a deepening of the zone of focus which somewhat masked the problem in some instances).

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