Debri is showing up only when the camera is shot in very low shutter mode.
how do I clean this out?
This looks like dirt on the sensor, it shows up during slow shutter speeds because you are using a smaller aperture (larger f number). Do a google search for camera sensor cleaning, there is a lot of information on the net as to how to do this.
"how do I clean this out?"
If you have to ask that question, you probably should let a professional shop clean the sensor for you. You can do a lot of expensive damage in the mirror box.
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