Hi agivney & welcome to IIS.
It sounds like you are on the right track with an ED80 & a decent GEM but I can't offer any insights on that particular combination. A good mount is key and a focuser that doesn't slip with one of your DSLRs attached is also very important.
What sort of objects do you wish to photograph? Deep Sky or planets?
Where are you located (which country)? If you can tell us a bit more about your situation then it might be easier to advise you on specifics.
Astrophotography can be frustrating at times whilst you are learning the ropes but also very rewarding. Enjoy the journey
