If it was on a filter is would be extremely out of focus and appearsoft and blurred.
You're correct, it would be blurry and out of focus if it were on the lens or filter.
?condensation on the sensor? I you take the drone from a dry place (your house) place to a warm, or humid place, internal moisture can cause condensation on the internal part of the lens or sensor. I have had this happen often with my DSLR when going out at night to do a star track timelapse. I have circumvented this condensation by putting hand warmers around my lens with a rubber band.
I was looking at this for star tracking and astrophotography...
These are much cheaper, Plus some rubber bands around your lens. Cannot be used for drone however
one howev
I buy a box for every season. They seem to last forever, and they keep well.
I'm thinking there might be a wee problem wrapping one of these around the gimbal/camera on a drone.... They do, however, work great on my hands and I imagine, on a camera. ;o)
. . . If you only use them for an hour or two you can put them in a ziplock freezer bag and squeeze*the air out and sue them again. The chemical reaction will stop as soon as the residual oxygen in the bag is used up. The ingredients are pretty common - iron filings, water, salt, activated carbon, vermiculite, and a few other things. Open the bag and knead them for a few seconds to restart the exothermic reaction.
