Thanks for rpineau's answer.It's very kind of you.
Hi dmf6978, your computer can run window 7 system, it also can run ASICAP and ASI120MC. ASICAP is as what rpineau's description.
You can see image with the camera putting fish eye, it indicates that the camera runs well.
If you want to watch Saturn or Mars, you should find it with your telescope first. Sometimes it will take great patience to find the target.
Once you find the target, you could plug the ASI120MC to the telecscope gently(GENTLY is very important). As you said, you should remove the right angle viewfinder first.
Run ASICAP and turn on the camera. If you could not see nothing except black, please change gain and exposure time larger.
Good luck.
Thank you.