AF Calibrator

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AF Calibrator

Post by GiantTristan » 23.01.2010 22:01

I have a trial version of Helicon Focus. I checked the AF calibrator with two of my lenses, Nikkor 70-200 F/2.8 and Nikkor 14-24 F/2.8 mounted on a D700. I used a sturdy tripod , good lighting and a suitable AF target. I am not very happy with the precision of the measurements, that is the repeatability of the adjustment value at constant distance, constant aperture and constant iso. Do you have any comment re. the expected precision?

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Stas Yatsenko
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Re: AF Calibrator

Post by Stas Yatsenko » 25.01.2010 14:52

We are not very happy with calibrator too. The first reason is that it is not possible to know if camera made step or not. In our tests with both Nikon and Canon cameras, both of them sometimes miss steps presumably due to mechanical issues. If the camera misses steps, the calculations in calibrator becomes invalid or unreliable. The second reason is that Nikon implementation of the live view is worse than in Canon. We zoom live view image to get more details about focused area. Canon makes true optical zoom and provides more details, Nikon makes digital zoom, simply resizing the central area of the live view. At least so it works with D90 and D300 cameras.

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