Visitors 1018
Modified 25-Apr-12
Created 16-Apr-12
15 photos

These shots were made to test the autofocus sensors in a Nikon D800. Lens is a 24-70mm f/2.8G at 50mm, f/2.8. Distance to plane of targets was 2.5m. Camera on tripod, mirror up, remote release. Click on any thumbnail to enter the gallery. Enlarge your browser window to see the largest versions of the images. Use keyboard right and left arrow keys to quickly switch between images. More details of the test method are at:

http:/​/​forums.​dpreview.​com/​forums/​read.​asp?forum=1030&​message=41240699

For these tests, the camera and targets were not moved between shots. Only the focusing point or focusing method were changed.

UPDATE #1: Since this gallery was first uploaded, someone informed me that the outer AF sensors are configured as vertical lines. I had thought that the outer sensors were horizontal (based on information from at least two sources). A few quick test shots confirmed that the outer sensors are indeed vertical, and sensitive to variations in vertical detail when the camera is in landscape orientation.

I repeated my original test, with new focus targets better suited for vertical line sensors. The procedure was the same as before, except that I taped the targets to a white wall instead of a window, and used the on-camera flash to get more uniform illumination (still not perfectly uniform). The results of the new test were similar to what I found before. The center AF sensor focuses correctly, but the outer sensors produce unacceptable errors, and the left-most sensor is the worst. Live View focusing works as expected. Images 1 - 8 are from my second test, images 9 - 15 are from my first test.

UPDATE #2: Since creating this gallery, I returned my D800, and obtained a D800E. Test results from that camera are available here.

Guestbook for D800 AF Test
NikonSnap(non-registered)
Apart dat bij jou beide kanten niet scherp zijn...

Ik heb het puur aan de linker kant.
Zie mijn test: http://forums.dpreview.com/forums/readflat.asp?forum=1021&thread=41653613

Heb jij al iets ondernomen om het te laten maken?
JW(non-registered)
Thanks for these photos. I have not done controlled tests like you, but I am experiencing the same thing: Outermost focus points inaccurate while center one(s) are accurate. Almost as if the focusing mirror is pivoted slightly at the center. I'm curious what you have or will be doing with your camera? Return it, or send it for warranty repair? I'm torn - normally I would just return it, but it is so difficult to get I'm tempted to send it for repair.
The guestbook is empty.
Loading...