Originally posted by twix23919
I'm looking to purchase just one lens right now....I find that I use my 18-55 kit lens the most, but I'm not happy with the quality. Here's what I'm looking at:
- Pentax Zoom Super Wide-Telephoto SMCP-DA* 16-50mm f/2.8 ED AL (IF) SDM
- Sigma 17-50 f2.8 EX DC OS HSM
What is the difference between the two? What would make one better than the other? Does the Pentax one allow you to use the 2.8 throughout the zoom? I could not find that in the description on B&H.......thanks ahead of time for your input!
First, YES, they
both let you have f2.8 troughout the zoom range.
The differences between the 2 are some times obvious, some times not:
1) Weather & dust sealed: Pentax Yes, Sigma No. When travelling the world (like we do) this is a very big plus for the Pentax.
2) AF motors: Pentax SDM, prone to failure, HSM not. Although my Pentax has lasted for 3 years and +100k shots by now...
3) Image Quality. The Sigma does better in tests at f2.8, the Pentax is soft in the corners at f2.8, one or more stops closed they are on par.
4) Size and weigth: Sigma is somewhat smaller, lighter.
5) Price: Sigma you should be able to get cheaper.
6) The Pentax is 1 mm wider, it sure makes a difference at the long end.
The latest Lightroom lens filters take care of all minor flaws like distortion, CA etc of the 16-50mm, I don't know if there are filters available for the Sigma yet.
I bought the Pentax 16-50mm 3 years ago and it has been my most used lens by far!
Sigma did not have the 17-50mm in its program then.
However, if I had to by a new standard lens today, I'd be having a very big dilemma: Sigma's IQ + HSM versus Pentax's dust & water sealing & 16mm....
Have a look here:
Pentax SMC DA* 16-50mm f/2.8 ED [IF] SDM - Review / Test Report Sigma AF 17-50mm f/2.8 EX DC HSM OS - Review / Test Report
Cheers, Bert