Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
03-06-2010, 05:07 AM   #1
Inactive Account




Join Date: Feb 2010
Location: thailand
Posts: 45
sigma 300mm f2.8 problems

I just bought a new sigma 300 mm f2.8 lens and the 1.4 and 2.0 converters.
The problem is the lens at 300mm is focusing bad. I can compensate for it in my settings but at +5 and +10. But sometime when close to the subject it is ok at 0.
I notice it really bad when i am photoshoping the photos. It is a huge difference.
Does anyone elese have the same problem or have you heard of the problem.

08-03-2010, 06:48 AM   #2
Pentaxian
Class A's Avatar

Join Date: Aug 2008
Location: Wellington, New Zealand
Posts: 8,934
QuoteOriginally posted by gary1952 Quote
Does anyone elese have the same problem or have you heard of the problem.
It is a well-know fact that lenses show different FF (front focus) or BF (back focus) behaviour for different distances. I cannot say whether your copy behaves within a normal range.

What is your testing methodology?

Here are some AF adjustment hints.
Reply

Bookmarks
  • 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!
300mm, f2.8, k-mount, lens, pentax lens, sigma, sigma 300mm f2.8, slr lens
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
sigma 8-16 problems? hoanpham Pentax SLR Lens Discussion 6 11-20-2010 08:14 AM
Pentax 55-300mm versus Sigma 70-300mm DG APO Macro mazdamazda Pentax SLR Lens Discussion 49 07-27-2010 12:46 AM
Tamron AF 70-300mm or Sigma Lens 70-300mm or Sigma 70-200mm Ben Hunt Pentax SLR Lens Discussion 21 11-05-2008 05:47 AM
sigma 100-300mm + k200d problems beverid Pentax DSLR Discussion 3 09-04-2008 05:28 PM
Sigma 18-50 f2.8 problems tarsus Pentax SLR Lens Discussion 25 03-15-2008 07:56 AM



All times are GMT -7. The time now is 12:22 PM. | See also: NikonForums.com, 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?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top