When I studied photography, students would usually put an A1 skylight filter over the lens to protect it. If you had dust or whatever on the filter, you could use lens tissue or even your cotton T shirt to clean it without fear.
My previous camera was an XL1 and i was a little more careful, had no filter, but after 5 years was using my t shirt directly on the lens (yes, i know, very bad boy)
"Dust off" is good, but is clunky and not convenient for running about since its big and heavy. Brushes with squashy back bits are ok but often get dirty themselves and just blow the dust elsewhere I find. Is a permanent protective filter possible/advisable what do you guys use to keep your lens dust free?
The key is this Schneider Optics stock code
Stock Code: 66-1001705
They make quite a few 77mm filters and I wouldn't be surprised if some are thicker than others various 77mm
Although the stock code I mention is the ONLY 77mm Clear MRC they make. Some will try to sell you Clear UV Haze filter which seem to have 2 versions 010 and 010M but those are HAZE filters and I want unaltered optics (or as close as one can get to it).