D600 OIL/DUST Report at 12,720 Shutter Count

First, as we've discussed before, I do think you have a particularly bad case of D600 dust/oil. In particular, debris placement is clearly biased toward that top left corner, more so than one would expect from random debris appearing on the sensor from normal use. I definitely recommend that you have Nikon address this issue, supplying them with all the sample pictures you've taken along the way.

OTOH, I think we have to be balanced and admit that we should be cleaning our sensors every 2K actuations or so, which is the interval you show here, more or less. For me, 2K actuations is one week of heavy use while hiking and doing outdoor photography, or 1 wedding over a few hours. It's good policy to clean our cameras after such usage. I may not do it out of laziness, but it's still a good idea.

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