Roy C
Occasional bird snapper
I doubt if you will find that much of a difference Nick - put it this way, if you cannot get good shots with the Tammy then you are unlikely to do so with Siggy either. If you are already getting good shots with the Tammy then you may get slightly better shots with a Siggy.Think I will probably sell my Tammy and get a Siggy. Just have to decide whether to get the Sports or the Contemporary!
With all these relatively cheap zoom lenses its all about getting close to the bird if you want really good detail, Obviously every birding lens ever produced will be better as you get closer but more so with these third party zoom lenses in my experience.
I will be getting my 'C' today so will post as to how I find it against the Tammy that I had.