D. Gregor Hagey CSC
Every time you change a lens on a digital camera such as the Red One, be sure to check the sensor for dust. The single CMOS sensor has a static charge that attracts dust (just like DSLRs). Use a loop to magnify the sensor before blowing gently with a blower bulb or compressed air. If blowing won’t remove the dust, then use a brush designed to clean DSLR sensors, but use it with great care.
When dust is left on the sensor it appears as a soft grey blob in the image. This is not always visible on small displays and might not be noticed unless you see your work on a large display or projector.