Mirror lockup isn't needed lol, the exposures arn't short enough. You can do mirror lockup vai apt anyhow with the 1100D using the live view simulation from what little i've read. Anyhow just experiment its the best way to learn, tinker with iso and exposure time. Using the 1100D along with a notebook and copy of apt or backyard eos makes life million times easier and less frustrating. It save a lot of time in the dark when your new to a dslr and everything can be done through the software, but you can also use the free canon utils which cost nothing to start out with
