Thank you for the quick confident response. I'll not abandon pumper type lenses due to this concern.
>>BOTTOM LINE: When in a dusty environment like a Renaissance >>Fair will using a pumper type lens like the new 24-120 F/ to >>avoid changing lenses gunk up the innards of my new D4 >>worse than changing trinity family lenses at the Fair? > >You are over thinking this. Just use common sense. You are >more likely to get dust in the camera if you change lenses is >a dusty environment. With the exception of underwater >cameras, No camera or lens is air tight. The D4 has the best >dust sealing in the Nikon line of DSLR's. >Have you had a problem with your D300?
It seems that there has been some small fall off in sharpness on my D300 w 18-200 mm DX lens combination in the last 4 1/3 years. 92,000 snaps on the D300, and about 130,000 images made with the 18-200.
A problem I did have was a tiny tick wandering into my D300 and then strolling around on the ground glass focusing screen. He eventually moved out of sight and is presumably dried up in some corner. I've not noticed any malfunction as a result.