from my experience with DSLR imaging, the key was to take all steps possible to increase signal to noise. For starters, I image from dark rural skies which helps considerably compared with an urban location. After various tests, I worked out an ISO and sub time that would give optimal signal to noise for my camera. This was about 3-4 minutes at ISO 1600 when I was using an uncooled DSLR, and then 8-10 minutes at ISO1600 when I used cold finger modded DSLRs. Making sure that darks and bias frames were temperature matched with lights was important, and then making sure collimation and focus were good during capture. I mainly used two telescopes - one with a focal length of 1278mm, and another at 650mm. I also had several images using Nikkor camera prime lenses which also worked well.
After that, my images made a huge leap forward when I started processing my images with Pixinsight - this allowed me to really pull all the data out of my images. From there it was then about extending total exposure to as long as possible - my maximum exposure was about 50 hours, with many images going for 15-20 hours or longer.
A lot of effort, but I think the resulting images hold their own, eg
http://www.astrobin.com/users/rmuhla...blic=&sub=year
Moving to mono CCD has been a further learning curve - i haven't been nearly as productive with my imaging since I made the switch for various reasons (work-life balance being part of the equation, as well as other equipment issues which have held me up, like my obs computers both needing to be replaced). Hopefully those issues are now dealt with, and I can look forward to more imaging in 2016.