I've been having some focus issues with my 35mm 1.8 lens on the Nikon D7000 so I printed out one of them AF charts and managed to get the profile for the 35mm spot on, however, I've tried doing it with my Sigma 10-20mm and at 10mm the top of the chart seems to be the only thing in focus, at 20mm the centre is in focus .. is there something special I need to do to tune a zoom lens?
Problems tuning AF for different lenses
- Thread starter Cuchulain
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Soldato
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- 15 Feb 2003
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I don't think the charts will work well with such a wide angled lens. as you need to set up the camera a certain distance away for the chart to work effectively.
This, for ultra wide angle lenses you will have to do field testing.
In general you have to take care when using the charts because you will get different results at different distances, but anything close to MFD will be especially skewed.
Thanks chaps, I don't tend to use anything other than F11 on that lens anyway so it's no biggie. For other zoom lenses (18-200 specifically) I'm guessing I'd be best snapping the focus chart at max. focal length where the dof is the most shallow?
In general that is a good idea, otherwise you can try to make an average across the focal lengths. If things are really bad then the lens will need to be sent for calibrating.
Soldato
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Or if you have to correct all your lenses then the body need to go for calibration.