Corner tests for 16-35 f/4 vs. 16-35 f/2.8 (v.1) vs. 24-70 f/2.8L II

Started Jul 4, 2014 | Discussions thread
Shop cameras & lenses ▾
Just another Canon shooter
Just another Canon shooter Senior Member • Posts: 4,691
Re: Corner tests for 16-35 f/4 vs. 16-35 f/2.8 (v.1) vs. 24-70 f/2.8L II

Abu Mahendra wrote:

I understand it alright. The idea is very simple. If one wants to Know how a lens resolves in any given spot, one focuses the lens on that very spot. If one wants to Know how a lens resolves at point X, one does not focus at point Y. It ain't I who does not get this elemental concept.

What you cannot understand, even after I explained it in other threads, is what to do when you want to maximize the sharpness across the whole frame. It may sound very weird to you, but this is what the majority of the UWA users want. Get it? You want the corners, the center, everything in focus.

Field curvature can easily ruin the corners. The sharpness in the corners may depend heavily on how far you focus (in the center). PZ explains in here. In such cases, the solution is to focus close. Here is a picture that says it all:

source: PZ

If you have further questions, write to Klauss.

 Just another Canon shooter's gear list:Just another Canon shooter's gear list
Canon EOS 5D Mark II Canon EF 15mm f/2.8 Fisheye Canon EF 35mm f/1.4L USM Canon EF 50mm f/1.2L USM Canon EF 135mm f/2.0L USM +4 more
Post (hide subjects) Posted by
(unknown member)
dil
dil
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow