Thoughts on the Sky-Watcher Wave 150i
The Sky-Watcher Wave 150i is an excellent mount for light-duty astrophotography.

My Lousy Astrophotography Blog
How long should my subexposures be? I’m not sure how many of us put a ton of thought into this. I myself have some rules of thumb that seem to work reasonably well for me. I’ve done a little reading on the subject, though and, basically, the answer is, “long enough, but not too long.” Not helpful? Thankfully, there are better explanations.