Micro AF adjust on A77

Hi guys,

I know that this has been discussed a lot around here, but I'm looking for your input:

- Is there anyway that I could look at what is saved in the registers of, assume a brand new A77?

- Is it possible that the registers already have values for unknown (to the camera) lenses?

- recommendation on Sony 50mm f1.4 lens.

Here is the full story: I've had the 50mm lens for a while but never been actually happy with the focus accuracy on my old A200.  I bought a brand new A77 recently and put on the prime lens to test it with the micro AF adj.  To my surprise there was a value on it already = -10.  After doing some tests trying to improve on this "initial" value, it proved to be the best value so far.  But the lens is still inconsistent and focus varies at f1.4 with probably 3mm on the focus chart .  So the final question is do I get rid of the lens or do I try to improve it, if there is a way to improve?

Thanks for reading,

rio