It takes a long time to choose a suitable specimen, a friend brought the same glass from Japan and is just perfect, sharp and accurate already from 1.4! Therefore, there is only one advice, very meticulously choose, come to the store with a tripod, a laptop (for viewing at 100% magnification), a friend (or girlfriend), seat a person and focus on the pupil (I think the test charts are not a very good solution, a little out of touch with reality, but useful for evaluating chrome and geometry) you can take it for adjustment, of course, but this is not a fact that will help, and it’ good review and testing of this lens.
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