D800 Report from Nikon Canada

Started Mar 23, 2013 | Discussions thread
YohmanYoh
Junior MemberPosts: 41Gear list
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Re: D800 Report from Nikon Canada
In reply to rdrebit, Mar 23, 2013

To make long story short: I guess, your camera is fine, but I would take a deeper look at the lenses.

I will tell you my service story afterwards, I hope this is helpful for you and others. If you get the chance to talk to a tech guy: Aks him if they have the right "new" testing equipment for the D800 and if they have done the primary and secondary mirror alignment check, too. This is mostly done at the first part of the adjustment course. The camera is fixed on a mount. A laser lights into the body and will be reflected on the mirrors. Finally the laser beam comes out of the body and points on a scale the current alignment value.

I had the opportunity to follow the Nikon guy through the whole testing parts for the lenses and the D800. Your screenshot gives the result of the the automatic calibration run against a horizontal and vertical striped target which is placed approx 1.2 meters in front of the camera. The camera is mounted on a fixed a extra calibrated 50mm Nikon lens. With that combination, the software tests out each of the AF-points and learns the camera the proper correction value to each field. The good range is up to +/- 70, so your results are very good for the camera (itself).

I asked the Nikon tech if it possible to get exact 0 to each value, but that seems to be impossible due to normal variations on each run and how the focus system works on every separate focusing. The focus has still some tolerances and every run will produce some minor changes in the values.

I personally was OK with that and got no pleasant pictures either. So we tested the lenses once more and more deeply. It comes out that my 24-70 2.8 is ok at the range from 50 to 70mm but it backfocuses much worse when it goes down to 24mm. The outer focus points were way out of focus while the center point was only bit behind. It seemed, that the the left side is a bit more worse, than the right one. On 24mm the focus is several meters behind the object. With that in mind, we calibrated the lenses on a special D200. It depends on the lens, but luckily the 24-70 has three adjustment points: At 24, 50 and 70mm. So, we fine tuned the lens at all 3 focal lengths. This gives an even behaviour through all focal lengths.

The real advantage is the wide angle part of the lenses. Trough the process the guy took a picture of a tilted fine checkerboard card with a vertical target in the middle. A special Nikon software then shows the point of maximum sharpness und a tolerance width. When measuring at wide angle the checkerboard becomes to small (more like a fuzzy gray card). Because of that it is hard to impossible for a proper judgement of the software and the human part, too. I guess, this is the weak point in the whole process.

If your Nikon employee is nice to you, he will take the time and take many pictures, compare them and do some additional fine tuning in the lens itself. If you can only have the standard procedure, the process and tolerances will give an proper adjustment on the 5 year old 10mp-camera - but not on todays resolution cameras. But that is only my personal opinion. In fact, with the standard procedure you will get an "ok"-adjustment, but there is still room to improve that.

After I was happy in the labs, I finally had to make an additional lens fine tuning in the camera, i.e. the 24-70 still at -9. Surprisingly, now the outer focus points are visually same as sharp as the center one.

A final word: After that, I made run through my pictures made with the "old" D700 and the 24-70 that performed so badly on the D800. Frankly, I had to say that the focus was nearly as bad as on the D800 - but less visible or noticeable because of the lower resolution. The D800 is such a high performer that every weak part becomes a significant and noticeable factor - particularly when checking with FoCal and 100% pixel views. Hopefully the Nikon will update its tests with lesser tolerances to respect the current cameras and lens combinations.

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