Well, I thought I would take a moment out to share with you the world's most boring before and after picture! I finally summoned up the courage to wet clean my sensor.
After spending a long time cleaning up some wedding photos recently I cleaned all my lenses, took some pictures of the sky, re-cleaned my lenses, took some more pictures of the sky, and realised that if the mark is in the same place with different lenses I would have to venture behind the mirror of my camera and touch ... the sensor.
I do have an Arctic Butterfly Sensor brush. It works by spinning the brush and building up a small electro-static charge that should pull dust off the sensor by gently wiping it. The trouble was that this time the mark did not appear to be dust but smudge marks. I don't know how they got on there, water, grease, I really don't know. The problem was that the Arctic brush was not going to remove them.
A lot of people shy away from using wet swabs to clear their sensor and why wouldn't you? You are about to stab the most sensitive and important component of you trusty x hundred pounds camera with a wet stick! Well, I've done just that and I am pleased to report that everything still seems in tact, phew!
Before, large smears around the edge...
After, all pixels appearing to be in tact!
I used a VisibleDust EZ Sensory Cleaning Kit consisting of 1 whole millilitre of Smear Away solution and 4 four Green Swabs for the disgraceful price of £16. The colour is important. You get different swabs for different size sensors. The width of the swab then covers the complete width of the sensor allowing you to make a single sweep across it. I turned the swab over and swept back in the opposite direction.
I hope this gives some of you the courage to do your own sensor if it is something you have been putting off. Now hopefully the only marks are the ones on my study wall.