Originally posted by stoge I'm looking at the DA*300 f/4 or Sigma 100-300 f/4. Which one has better IQ?
Stoge:
Until 2 days ago, I owned both the Sigma 100-300 F4 and the DA*300 F4.
I just sold the Sigma because there was no point on carrying two large lens during my outings. Nonetheless, the Sigma, in my own opinion, has a similar IQ as the DA*.
Take a look at some of the pics at Pentax Photo Gallery (link below my signature) and you will see that any bird photo which has been taken with "other" (i.e.: other than a Pentax lens) was in fact taken with the Sigma. (Snowy Owl, heron ...etc.)
I liked the versatility of the Sigma "zoom" but it added weight to my gear. I very seldom use a tripod/monopod, so it was a bit bulkier than the DA*
Other than that, I like(d) both lenses for the IQ, mounted on a K20D.
So, it depends if you want a lens with more versatility or a prime which sort of restricts your latitude, but I would say this prime lens is light, fast and easy to handle under harsh conditions,plus it is weather-sealed.
Hope this helps a bit.
JP