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Old 29th February 2008
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Re: EC-14 for Walkabout

Quote:
Originally Posted by Pjphoto59 View Post
Musicman,



I would be wary of using it with the 70-300, which I think has a max. aperture of f5.6 (at the long end). With the EC-14 your max. aperture becomes f8, so it must be dark for viewing and a challenge for the focussing. This is partly why I am thinking of an EC-14 rather than an EC-20, with my my 14-54 and 50-200 I will get a max. aperture of f5.6, rather than f8...

Thanks for your comments.
The problem here is that the 70-300 @ 300 is already down to f/5.6. With the converter, you lose another stop to f/8. I would suspect that the lens would really benefit from stopping down a little - so let's say f/11, but that's well past the sweet spot for 10MP four thirds cameras (f/5.6, roughly).

Just as an experiment, try using the lens wide open when using the converter. Maybe having less diffraction softness will be better than having improved sharpness by stopping down a stop?

Ian
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