Originally posted by GaryML I use a Nikon D80 with four different Nikkor lenses. For low-light, interior use, I usually use the Nikkor AF-S 17-55mm f2.8 DX lens, sometimes with an SB-800 Speedlight. After using this equipment for about 5 months, I've found the AF accuracy to be very good. Almost all shots are correctly focused (better than 95%). It does better than my Pentax K10D in this regard. All the reports I've read indicate that the D300 AF performance is superior to the Nikon D80, so I would expect similar or better AF performance with used with an f2.8 or faster Nikkor AF-S lens.
I have no idea why your brief test in the store yielded poor results. Perhaps that particular sample was defective, or the camera fine focus tuning was mis-adjusted, or you used slow lenses, or a problem with Sigma lenses, or whatever. Perhaps your lack of familarity with the camera caused you to make some operational error in your test. I don't know. But I do know that if there was an inherent defect in the D300 AF to the degree that you claim, it would a major issue for Nikon and it would be reported in the photo press. After all, they are selling about 70,000 of these camera per month since the end of November, 2007.
I doubt very much that there is a problem with the D300 AF. On the contrary, the D300 was described by Popular Photography in the February 2008 issue as having the best low light AF of any camera that they have ever tested.
Gary, I have to agree with your comments.. I was very disappointed with the result, and the comments here have been fair for the most part on either side of the fence. I would feel really bad if it was my inexperience with the Nikon that caused the poor result, so much so I have requested a second evaluation.
This time with the camera properly set up. To be fair, the camera was taken out of the box, the salesperson looked it over and put in a battery, I purchased a card and tried out several lenses I was familiar with. My experience with both Sigma and Tamron on the Pentax has been excellent, so I would not place any import on the non Nikkor lenses having any effect in this.
This time I will take more time, and also take my Nikon wielding son with me, with his lenses and expertise to review again. While I love my K10D, and certainly the lenses are equal to anything else out there, I do want to be fair in this.
I find the K10D a perfect fit for me with a few major exceptions; Low Light Focus, Continuous Focus and External Flash Effectiveness. These to me are rather critical to my photographic preferences, and after 45 plus years of extensive experience with many cameras, I need to resolve them one way or the other.
I will be back to you all later this week...... thanks for the responses.
Phil