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Old 21st November 2011
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Nick Temple-Fry Nick Temple-Fry is offline
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Re: focus issues with polarising filter

Originally Posted by ianbirkett View Post
Thanks for all the ideas. I have IS switched on by default, I'll try switching it off and see if that makes a difference.

Regarding the DOF comments, I remember the viewfinder telling me it was focusing on the mid-ground rather than foreground. Also, looking at the high-res images the foreground isn't sharp either.
I suspect you haven't warmed to the dof argument, fair enough, it may be wrong. But if it was confirming focus around the centre point, which was for argument 40ft away, then everything under 25ft would be oof, as would anything over 110 ft. Which would give an appearance similar to your Leighton Moss shot.

On the Constantine Bay, a centre point focus would be around the boundary between grass and the more distant beach, quite likely on the edge of the grass. At 14mm F5.6 then if that edge was 15 foot away then everything from about 5 ft to the horizon would be sharp. A 14mm lens goes 'hyperfocal' at 5.6 just below 8ft, which gives you dof of about 4ft to infinity.

Nick Temple-Fry

Medicine as a science ranks somewhere between archaeology and economics. 90 Churches -- Fairford St Mary's, exceptionally splendid
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