Originally posted by Marc Sabatella they somehow do actually work.
Hi
from they way you phrase your retort, "...somehow do..." I deduce that the physics of how hummingbirds actually stay aloft is somewhat of a mystery to you. The physics of that is generally well understood.
I can now see why the prospect of the aforementioned likelihood of a piece of fluff not falling out of a down pointed camera mount opening after it has been dislodged from the sensor by a blast of air is something that is not generally understood. Sure these blowers work
sometimes but what happens to the fluff? If the fluff got removed successfully that's all that matters -is it? Is it a case of "out of sight - out of mind?" Well perhaps for the moment, but I bet it'll be back.
Permit me the liberty to explain.
When you attempt to shift a piece of matter which is stuck on a sensor with a blast of air the force (strength) of it not only has to be strong enough to carry the weight of this matter but also it has to be strong enough to overcome/break the bond that holds the matter onto the sensor surface. This suggests that a pretty strong force of air velocity is required.
Now if with one strong puff of the blaster you are successful in dislodging the offending matter and it gets successfully carried away from the sensor, any subsequent puff of air following in quick succession (people customary do 4-5 quick blasts) will not allow this matter to find its way down through the camera opening for the simple reason that the piece of fluff you have just removed will not be heavy enough or has propulsion of its own to overcome the force of air coming towards it. Also please consider the turbulence you have created in this confined space.
The most likely result will be that, whatever you have removed from the sensor, will be carried to some far corner of the mirror chamber and in all likelihood will attach itself anew on some surface. But if it is still free floating inside the chamber it will not be in front of the mount opening because this is the direction from where the blast of air originated. And if it still floats around somewhere inside the chamber I can't see that the fluff will do a u-turn and head for the opening. My understanding of physics is telling me, all you do is re-locate the dirt and it can attach itself onto the sensor again. So my preferred method of dirt removal would be
"removal."
So, if blowers remove dirt only temporarily then I say they actually do not work.
Greetings