Forgot Password
Pentax Camera Forums Home

Show Printable Version Search this Thread
03-19-2010, 09:42 PM   #1
Veteran Member

Join Date: May 2009
Location: Ankeny, Iowa
Photos: Gallery
Posts: 388
Pentax 1.7X AF Teleconverter with Sigma 100-300mm/4?!?!?!

Would anybody know if Pentax AF 1.7X Teleconverter would work well with Sigma 100-300mm/4?
if so, would you post a few pictures?
or do I have to test it out after I get my 1.7X TC? lol

03-20-2010, 02:04 AM   #2
Loyal Site Supporter
Loyal Site Supporter
imtheguy's Avatar

Join Date: Mar 2009
Location: Virginia Beach
Photos: Gallery | Albums
Posts: 2,950
Buy the TC and have fun with it. I guarantee you can easily resell it if you don't like it. Check with PF member tom1803 for a new one at a fair price.
03-20-2010, 03:01 AM   #3
New Member

Join Date: Nov 2009
Location: N52.157643, E20.708963
Posts: 13
Such combo works *very* fine.
You have to isolate some TC's pins to have correct exposure.

-- M.
03-20-2010, 04:04 AM   #4
Veteran Member
borno's Avatar

Join Date: Nov 2006
Location: md-usa
Photos: Gallery | Albums
Posts: 2,580
When I tried the 1.7x afa on the sigma 100-300mm f4 I used the aperture ring because the lens didn't close down to where it should have. Maybe this causes the exposure error? For example I like to use f5.6 alot, but the lens would show f2.8 wide open (IIRC) and stopping it down 3 clicks it would still shoot wide open (i discovered this by looking into the lens with DOF preview) until you got to around f8. It worked fine with the aperture ring though. Maybe others didn't have this problem. I used mine with the kenko 1.5x shq and that was a very good combo.

03-20-2010, 11:14 AM   #5
Veteran Member

Join Date: May 2009
Location: Ankeny, Iowa
Photos: Gallery
Posts: 388
Original Poster
Thanks, yall! I've just bought the 1.7X converter from Tom, it should arrive today or next Monday, I've gotta try it out. Well, I supposed that I can use it with my FA* 80-200mm as well, mine be a better fit(performer).

  • 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!
1.7x, af, k-mount, pentax, pentax 1.7x af, pentax lens, sigma, slr lens, teleconverter
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Similar Threads
Thread Thread Starter Forum Replies Last Post
sigma 100-300mm f4 or pentax 300mm f4? powdablu21 Pentax SLR Lens Discussion 10 09-08-2010 05:14 AM
pentax 300mm f4 or sigma 100-300mm f4 kuau Pentax SLR Lens Discussion 14 11-29-2008 09:05 AM
Sigma 100-300mm f/4 versus Pentax DA* 300mm f/4 Tbear Pentax SLR Lens Discussion 5 03-26-2008 07:24 PM

All times are GMT -7. The time now is 02:34 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]