It seems that I have a very stubborn particle on my sensor. I've wet cleaned it about 15 times (!) and the sensor is gleaming clean, except for this one spot. I've checked it out with a scope and it looks like something on the sensor.
It starts appearing (smudge) at F8, and show nicely at F22.
I think this might be a professional cleaning job (aka Nikon)?
Any advice? I've tried a blower, brush, wet cleaning...maybe a sensor pen?...
You could see if there are any certified Nikon repair centers in your area and see if you can have them clean it while you wait.... I don't know if they do this, but would be nice if they would.
I feel if it's showing up by f/8, I would be concerned also.... I've only had to wet clean mine (a few try's) once. Mine had some oil on the sensor, only reason I know was I tried using a brush first, and it smeared whatever it was on the first pass. So it took a few wet cleanings that one round and mines been fine.
I have been very happy with the Quasar Sensor Loupe from VisibleDust. It was pretty espensive - around $95; but really performs very well. It's the only one I have ever used, so I can't compare it to anything. But, I felt like the technology behind its design lived up to the performance promised by VD. Check it out.
My D800e is a dust magnet and I am cleaning it at least once every week. But so far I have used only a small blower pump and a SensorKlear like in that video. One time I used the brush I bought for $3 with nylon bristles from the art store because sensor was particularly dirty. After I bought the brush I washed it 3 times with hand soap because all brushes have glue on them. To electrify the brush I use Datavac Duster. This device has filter on the bottom so air is clean. It is just to strong to use it on the camera. Any remaining dust I remove with SensorKlear by flicking it. No, not polishing it. The only thing is that I know people from the this company and long time ago at CES I was given to try one of the versions of SensorKlear that has flexible tips. The problem with SensorKlear brush is that diameter of it is larger than the tip and it can't get to the very corner on FF camera. No matter how many times I complained about it for some reason they refuse to fix it. But with the flexible tip I can just bend it so the body stays away from the corner and I can reach there with the corner of the tip. Simply blowing the tip with Datavac cleans it so it can be used forever. Also company just came out with a new loupe which uses AAA batteries. I don't have it yet but I do have their older version. This loupe has cutout so you can use your tool at the same time as the loupe. No guess work there.
So you don't need sensor stamp or that spinning brush. Just SensorKlear and a good blower.
I must admit my D800 seems to attract more dust and needs more cleaning than my D700 did or D7000 does. This week I had a stubborn sensor spot which showed up large on the attached image above and to the left of the Goldfinch's head as you can see.
This wasn't dust as using my Rocket blower and visible dust static brush failed to remove it. I did a wet clean and as expected it smeared on the first clean. When that happens I've been instructed to clean again with a new swipe. This time it disappeared. Guess it was an oil spot as I am very careful when changing lenses to tilt the camera forwards.