Last night I spent some time checking the AF accuracy on my K10D, K20D and new K-r. This was done to see if my K-r was front-focusing like I expected. The results, unfortunately, speak for itself.
My test configuration consisted of the following:
- Camera mounted on tripod and positioned at a 45 degree angle towards focus test chart. (See Nikon D70 Focus Chart)
- 2 second delay to minimize camera shake.
- Custom white balance performed.
- Center-point focus selected.
- Center-weighed light metering.
To see if patterns existed, I used three different prime lenses (DA 40mm; DA 35mm Macro; FA 50mm). I also performed separate tests for tungsten and daylight-balanced lighting.
For now I will just post images that were captured using the FA 50mm f/1.4. The results were identical across all lenses I tried. You will clearly see that both the K-r and K20D front-focus in tungsten light. The K-r, however, is in a league of its own. Even with the focus adjusted to -10, front-focus is still an issue.
The results were much better once daylight-balanced bulbs were screwed in. The K-r still front focused but its performance was acceptable.
I apologize in advance for the lousy exposures. I was concentrating on getting things lined up and focused properly.
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Without further adieu, here are the images:
K-r w/FA 50mm f/1.4 (Tungsten):
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K-r w/FA 50mm f/1.4 (Tungsten) FOCUS ADJUSTMENT SET TO -10:
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K20D w/FA 50mm f/1.4 (Tungsten):
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K10D w/FA 50mm f/1.4 (Tungsten):
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K-r w/FA 50mm f/1.4 (Daylight-Balanced):
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K-r w/FA 50mm f/1.4 (Daylight-Balanced) FOCUS ADJUSTMENT SET TO -10:
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K20D w/FA 50mm f/1.4 (Daylight-Balanced):
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K10D w/FA 50mm f/1.4 (Daylight-Balanced):
Last edited by krebsy75; 12-24-2010 at 02:31 PM.