Hi can people please tell me what midi keyboard they would recommend to use with cubase and specifically halion sonic 2. I want a full 88 key version. I was hoping yamaha made one but they don’t seem to produce a dedicated midi keyboard or have I missed something?
Here’s my 2 cents speaking only as a musician. Although most any good MIDI instrument will work, I believe the keyboards that will give you the least amount of trouble with a Cubase setup will be Yamaha. It seems you must be a piano player - so you will be looking for an 88 key instrument with balanced weighted keys or some kind of graded hammer action. You want it to play like a piano. If that is what you want, you will find that all of the Yamaha instruments will be more than just bare MIDI keyboards. They will include their own sound module, sequencer, FX and so on. But that’s OK - you won’t use that part of the device when controlling Halion instruments. Besides, the money is in the key action. The high end stuff, like the Motif XF series might be too much cost for you, but an MOX is a good instrument and the cost is reasonable.
What you’re looking for is technially called a MIDI keyboard controller. Yamaha used to make the KX series but I don’t know if they’re weighted. Maybe look on EBay for “88 Key MIDI Controller Keyboards”.
I don’t think there is a “best” one, but I have always used a M-audio axiom 61, and it has been a great workhorse. Get something USB, as it’ll make your life a lot easier 
The yamaha MX49 might be the one…