Forgot Password
Pentax Camera Forums Home

Show Printable Version Search this Thread
11-07-2009, 01:15 PM   #1
Veteran Member
code4code5's Avatar

Join Date: Oct 2007
Location: Denver, CO
Photos: Gallery
Posts: 438
Sigma 17-70 at 50mm - Very Wide Images

Hopefully this will help others considering purchasing the Sigma 17-70 DC. Not that it's at all bad, but performance certainly does peak around f/8. This test was related to my earlier thread ( Here is a test of performance at all stops between f/4 and f/22.







All are a one inch tall 100% crop to demonstrate edge to edge sharpness. Each was processed in Bridge using default settings, manual WB and exposure in camera, on a tripod, with 3s MLU.

11-07-2009, 01:46 PM   #2
Community Manager
Loyal Site Supporter
Ash's Avatar

Join Date: Mar 2007
Location: Toowoomba, Queensland
Photos: Gallery | Albums
Posts: 22,691
A good standardised test.
The subject is 3D no doubt? So are the corner details on the same plain as the central details?
If not it would be hard to distinguish between lens blur and gaussian (OOF) blur.

But thanks for sharing this.
11-07-2009, 10:22 PM   #3
Veteran Member
code4code5's Avatar

Join Date: Oct 2007
Location: Denver, CO
Photos: Gallery
Posts: 438
Original Poster
The extreme left side was closer to the camera than it should have been in that respect... Thanks for pointing that out, Ash! It just seems as though so many "vs" threads are very subjective. I'm not an official measurbator, though.
11-08-2009, 04:04 AM   #4
Senior Member
campdog's Avatar

Join Date: Oct 2009
Location: Bonny Hills, NSW, Australia
Photos: Gallery
Posts: 202
I got the 17-70 before a trip to Samoa in may this year. Its my favorite everyday lens. I got some fantastic landscape and portrait shots.I highly recommend the lens.


  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
edge, f/22, f/4, f/8, k-mount, pentax lens, performance, sigma, slr lens, test
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Similar Threads
Thread Thread Starter Forum Replies Last Post
How to upload / link photos - BEGINNERS START HERE Adam Post Your Photos! 191 05-17-2017 06:25 AM
For Sale - Sold: Sigma 24mm 2.8 macro super-wide II; Sigma 20-40mm/2.8 DSims Sold Items 14 11-18-2009 05:30 PM
4 Lenses at 50mm - Very Wide Images code4code5 Pentax SLR Lens Discussion 1 11-09-2009 02:11 AM
FA77 and DA70 WIDE OPEN images: Let see 'em! maxwell1295 Pentax SLR Lens Discussion 31 05-20-2009 10:02 AM
For Sale - Sold: Pentax-F 50mm F/1.7 + Sigma Mini-Wide 28mm F/2.8 Macro barbosas Sold Items 3 08-21-2007 10:52 PM

All times are GMT -7. The time now is 11:15 PM. | See also:, part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]