Hi again Will
When trying to evaluate the pro's & con's between the Sigma and Tamron lenses, as I said earlier in this post:
Quote: I've never actually seen a Sigma 17-70mm in the flesh before
whilst also adding into the equation Bert's initial conclusion that:
Quote: There are two things the 18-250 Tamron specializes in: 1. dust prevention, 2. startup time. You will be prepared for almost every situation.
It would obviously be inappropriate of me to comment on the optical superiority or otherwise of the Sigma 17-70mm, but bear in mind that
neither of these are
prime lenses. Therefore it
may be that the quality of one wins out slightly over the convenience of the other ! All I know is that I have been surprised and delighted by the excellence of the shots I am currently obtaining with my Tamron 18-250mm Di II lens.
Incidentally, although I now have the funds in place to obtain one of Sigma's fantastic 10-20mm DSM superwide-zoom lenses, frustratingly the UK distributors of Sigma have recently been the recipient of not only ONE but unbelievably TWO major break-ins at their warehouse in the last few months. Every well-known photographic store I have contacted is presently out of stock of this lens in Pentax mount, so I have little alternative but to patiently wait in the queue until the next consignment arrives by container from Japan......Grrrrrrr !!!!!
Best regards
Richard