Say a visit to the Nikon Service Center is too troublesome for you and you want a bit of DIY satisfaction with the maintenance of the Nikon D90. No lint-free cloth will do the job when it comes to cleaning the fragile sensor grid.
It's an occasion to utilize the "arctic butterfly" toolkit. So with some spare cash to spare, this magnificent tool features a bright LED that illuminates the sensor while in operation. This illumination reduces the possibility of fibers being dragged accidentally against the surrounding cavity hence reducing the potential cause of smear usually caused by contaminated fibers.
Get yours [here] for $90.