My next D7000

[bruce_rubenstein]

<p>The reason why that is a<em> LOUSY, repeat, LOUSY test target</em> is because it is very low contrast. If you are trying to determine if the AF is accurate, the AF has to be presented with a target it has no problem focusing on. Why, in this instance, the 300 had less problems focusing on the target than the 7000 has nothing to do with the accuracy of the AF system.</p>

<p>It might also be useful to read <strong><em>Focus Fallibility: Lens Test Fallacies</em>, </strong>http://www.slrgear.com/articles/focus/focus.htm</p>

[ilkka_nissila]

<p>I'm not a believer in the "frequent bad copy" theory. I have used many autofocus Nikkors and cameras and never ran into a "bad copy" that didn't function correctly. I have had two lenses which required autofocus fine tune on my D700 and D3, but that's about it. I have tested my D7000 extensively in practical applications as well as carrying out a few controlled tests of the AF. If you have a clear subject with high contrast detail and where there is no confounding detail right behind or in front of the main subject (as you have in your test image; the background is very close to the main subject which can cause the AF system to be confused) the D7000 should focus accurately; mine certainly does in controlled conditions.</p>

<p>However, in real-world shooting I have been prolific in producing out of focus images with the D7000 so I can understand your pain and desire to get better AF from it. The 18-200 is not an optimal lens to use on a D7000 - try to get a hold of some f/2.8 Nikkor zooms such as the 17-55 and 70-200. I have found practical AF results to be a lot better with e.g. the 70-200II than zooms that end at f/5.6 maximum aperture at the long end (e.g. 70-300 VR). You're not going to discover the true capabilities of the D7000 with that 18-200.</p>

<p>Complaining to Nikon is not going to do much. Nikon knows very well that the D7000 AF system is not as good as that in the higher-end models. You already had your D7000 checked by Nikon and they found no fault with it. I don't expect your new copy to be any different. If you want high-performance autofocus you have to pay for it. Nikon makes a lot of money from their more limited DSLRs but they have to provide significant incentives for demanding customers to pay for the much more expensive cameras such as the D3X. So they leave out something that would be desirable - such as the Multi-CAM 3500 from the D7000. (No, I'm not suggesting that you buy the D3X. Be patient. Nikon will eventually combine the D7000 sensor with high-performance AF).</p>

<p>By the way Bruce: real-world subjects often have low detail contrast, and confusing backgrounds, so in a way the test is not completely bad. It's not good for testing whether the D7000 is functioning correctly (as other D7000's would) though - I agree on that. But nevertheless a <em>good</em> AF system will function well in such a test also.</p>

[bruce_rubenstein]

<p>No, it's really a bad target because if the subject is out of focus there's no way of telling why. Tests/experiments are only useful if there is one variable. If it can be established that AF accuracy is acceptable using a proper target, then one can move on to lower contrast subjects. Problems with low contrast targets can be due to design limitations of the AF system which can't be corrected by <em>adjustment</em>, whereas accuracy can be. Can't fix a problem unless you know what it is.</p>