A question or two

I have a sigma 17/70 and a Tamron 70/300 which I am happy with both. My question is if I purchase a Tamron 18/250 can I expect better picture quality over the Tamron 70/300 which would meen I could get away with the use of the single lens, less the 50mm focal length. Also does anyone know how the Tamron stands up in performance and pic quality to the pentax 18/250.
Ian

The Tamron and Pentax 18-250 are the same lens. But each brand puts it's own coating on them. I think the Pentax coating is better than the Tamron, but that feeling might not be shared by everybody. I don't think it would improve the picture quality above what you are having right now, since the 18-250 has more distortion at both ends than your combination of lenses. The Sigma 17-70 is also a cut above the 18-250 (at the same range) when it comes to image quality. BUT you can't beat the versatility of a do-it-all lens. A lot of points to ponder!

Hi Ian I just bought the Pentax 18-250 from a forum member and it has not been of my camera since I just love it If you look at my portfolio most of the photos on the last 2-3 pages have been taken with it, I was going to go for the Tamron but I have been a little disappointed in my Tamron 70-300 I would go for the Pentax at least it matches the camera.

Sigma is also coming with a 18-250 lens but with HSM, so it will focus faster (tamron and pentax are rather slow) and you have manual focus without using the switch on the camera.

I almost never use the DA 18-250, only when I need to range.
Just not a lens for me

Think I may just stay with what I have for the time being and may be carry the two cameras with lenses that will suit the job.
Ian

The penalty to pay for any zoom, but especially these 'super' zooms is distortion, which is often very pronounced and is usually at both of the extreme ends of the zoom range...so if you are happy to have distortion, buy zooms, if not....

cheers Steve.