1st post here. I am a long time "lurker" and have read many threads on this site for information/advice.
Sorry to dredge up an old thread, but I found this while researching debris issues with the 1DX.
After saving for quite awhile, I finally took the plunge and bought one of these with he bundle deal that was advertised on the CR site last week. I can't tell you how excited I was to have one of these to call my own!
I received it on Friday afternoon and took it out to shoot on Saturday. The very first time I pressed the shutter (high speed mode) several black particles appeared in the OVF. The more that I used it, the more particles appeared.
Upon review of the images, there is visible sensor trash at f/6.3! So I tried f/22. I could not believe the results. Less than 400 actuations and a dirtier sensor than I experienced in the three years that I have owned the 5DIII.
Here is where I screwed up...I tired to clean it. The sensor had a combination of oil and black particulate "chips" on it. I used "air rocket" and the sensor brush that I have used on the 5DIII. I think I got the sensor reasonably clean. I turned my attention to the focusing screen...I lightly blew air on it and gently brushed it with the sensor brush...there must have been some particulate from the sensor on the brush and I scratched the focus screen.
The camera is now on the way to CPS for service. I should have never attempted to clean this thing. After reading some of the experiences posted here and other places with debris problems similar to this one, I just hope it gets fixed correctly the first time around....fingers are crossed!
I know that there are so many people that have had (and continue to have) great experiences with this camera. I really wish I could say that mine was one of them right out of the gate...