Why not just enter your data into CCDCalc, it gives all the answers...
http://www.newastro.com/book_new/camera_app.html
This shows a FOV of 82 x 108 arc min (1.36 x 1.8 deg)
(For the 150/ f7 the FOV would be 44 x 58 arc min)
EDIT: to achieve your 3.4 deg field, you must have a reducer fitted which brings the EON focal ratio down to f3.5...