sensor cleaning for digital camera is such an expense if you decide to get it done professionally ( I was quoted £120 recently, but other cheaper options were available). I clean my own sensor ...and have tried many products and all failed to remove a particularly stubborn lubricant blob on my sensor that was ruining my images except www.copperhillimages
whose eclipse solution in combination with the sensor swabs did the job. Also really detailed instructions with images and diagrams that explain the process.. easy peasy Highly recommended.
I will be adding more endorsements when I get the time