To reduce exposure levels I use Double Polarizing Filter and adjust it to what level I want, but I use a DSLR a lot for moon and find there is no need for long exposures or that filter.
When I am fit enough I hope to use my DSLR all the time in place of my webcam but I know that all I need to do is alter the exposure of the camera even when taking video.
Are you considering single image or stacked multiple images.
My best single shot -
http://www.waelect.com.au/mswhin63/M...w/index.html#7
I do use a double polarising to reduce exposure on my webcam at high resolution but not on my DSLR - Webcam -
http://www.waelect.com.au/mswhin63/M...w/index.html#4
My super close-ups are with webcam only but hope to change to DSLR again now that I can take high frame rate video.