I've have had some serious time to ponder DUST during my 3 weeks shooting in the Atacama Desert on Cerro Llullaillaco (the 4th highest volcano in the world). On it's own, the Atacama is an amazingly dusty place with lots of particulates and the lowest rainfall of any non-polar region on earth. To make matters worse, the South side of Llullaillaco is exposed to the dust plume from the Escondida Mine, one of the largest copper mines in the world.
So, here are a few tips I utilized to keep my sensors and glass clean.
1. Have a clean place to work with your equipment.
Most of my time in the Atacama and on Llullaillaco was spent outside shooting the action taking place, but I stored all of my equipment in one of our trucks where I could clean it away from the dusty air and the constant wind.
Of course the truck was not a perfect option since it was not dust free but it allowed me a quiet and clean(er) place to deal with the dust that inevitably ended up all over my equipment.
2. When in the field and not in use, keep your camera covered.
I kept my camera in it's case whenever I was not actively shooting. This included keeping the lens cap on whenever possible. For this trip I used a LowePro Toploader Pro 70 that I could wear over my shoulder so that I was able to have the camera covered but out and at the ready simultaneously.
I broke the lens cap for my 'run and gun' lens (Sony 24-70mm f/4 ) early into the expedition. Needing another option I built a makeshift cover utilizing the lens hood, cardboard and duct tape. This extended down the length of the lens covering the focus and zoom rings, and helped to keep them dust free which ended up being even better than the stock lens cap. Clean living through improvisation!
3. Use a filter.
A filter is easier to clean and protects the front of the lens from damage. Since I was shooting video it was fortuitous that using an ND filter was necessary in the harsh light of the desert. For this shoot I was utilizing the Syrp variable ND filter. When I did not need the ND filter I was utilizing a UV filter in order to protect the front optics of my lenses.
4. Be careful with lens changes.
It is when you change lenses that you are most likely to get dust in the rear optics of your camera or on your body's sensor. Make these changes carefully and constantly check the sensor and glass for visible dust. On Llulliallaco, every time I made a lens change in the field I ran a sensor cleaning through the camera menu (I was using a Sony A7 Rii). Within my camera bag I always carried a small hand pump air blaster and microfiber cloth so that I could take care of any persistent bits of particulate matter that the sensor cleaning didn't remove.
It is worth noting, be ultra careful with the sensor, it is delicate and you really do not want to damage it.
5. Clean all your equipment often
Whenever possible, clean your equipment every day. Be careful and be thorough. For a great guide on how to clean you camera see this article [http://www.bhphotovideo.com/explora/photography/tips-and-solutions/how-clean-your-lens-and-filters].
6. Bring some trash bags with you for emergencies when you just need to get your gear away from the elements quickly. Even better, bring an airtight housing along which will protect you from dust, rain, splashes, etc. We like the Outex modular camera case.
7. At the end of the day, gear is meant to be used so don't stress about the tech so much that you take your energy away from making great images. The dry dusty parts of the world can yield amazing images; don't be afraid of hurting your equipment, go get involved, keep it clean and make something beautiful.