Photo quality falls when importing from CS5 raw to photoshop

Thanks everybody for your help and sorry for the delay in my reply. You were all very helpful and thanks for taking the time to reply. It seems the problem was with my GPU settings. Once I enabled that all seemed to be well again. I just installed CS6 on trial and that does it all automatically -  a much better idea.

On the CS5, I had set to non-gpu rendering...and that seemed to be causing the problem.

Many thanks again all for your kind help.

Tiggle.