Forgot Password
Pentax Camera Forums Home

Show Printable Version Search this Thread
06-07-2013, 09:00 PM   #16

Join Date: Apr 2007
Location: Oklahoma USA
Posts: 1,503
I don't understand the discussion of OS on the new Sigma. I owned this lens briefly and as far as I know the new Macro 18-250 doesn't have OS in Pentax mount.


06-08-2013, 07:09 AM   #17
Senior Member

Join Date: Mar 2013
Posts: 138
Original Poster
QuoteOriginally posted by tibbitts Quote
I don't understand the discussion of OS on the new Sigma. I owned this lens briefly and as far as I know the new Macro 18-250 doesn't have OS in Pentax mount.

My bad. You're right. Amazon didn't note that, but the Sigma website does.
06-08-2013, 07:38 AM   #18

Join Date: Oct 2011
Location: Savannah, GA
Posts: 5,002
I have the 18-250 as my main walkabout lens. One thing to note is that at the long end, it only gets to 250mm when focused at infinity. For closer subjects, it seems to top out at about 180mm. (But it can also focus at only a foot or so at all zoom settings.) How the Sigma does in this regard I'd like to know.
06-08-2013, 09:43 AM   #19
Site Supporter

Join Date: Jul 2009
Location: Montco, PA
Photos: Gallery | Albums
Posts: 135
my 18-250 Tammy is one lens I will (probably) never part with. The image quality may not be on par with prime lenses, but it's definitely the most versatile lens I own. The only real weak point is AF capability in sub-par lighting (indoors, shade, etc.). Here's a small set of some of the better pictures I've taken with this lens.

Unfortunately, I can't comment on the Sigma. When I was in the market (about 3 years ago), all of the comparisons I read led me to choose the Tamron and I haven't regretted that decision. Since most of the low-light shooting I do is in a narrower range of focal lengths, I added a Tamron 28-75/f2.8 to complement the 18-250.

Last edited by wedge; 06-08-2013 at 09:49 AM.
06-08-2013, 10:12 AM   #20
normhead's Avatar

Join Date: Jun 2007
Location: Near Algonquin Park
Photos: Gallery | Albums
Posts: 25,861
I don't know if you saw this thread here....

These two lenses from what I understand from my research... the Tamron/ Pentax is more center sharp but not as good edge to edge. The compromise in the Sigma lens was made to achieve less distortion and to control CA. As well the Sigma is weak in the middle but from what I could see, of the super zooms it is stronger in the long end than any other super zoom. And it's probably the best control of distortion and CA in the wide end makes it an excellent landscape lens, for a super-zoom.

Pentax/Tamron seem to favour the centre sharp over everything else approach. Sigma is putting a lot more effort into distortion and CA control. They are both valuable approaches, to the point where my wife and I have decided me with my center sharp 18-135 and her with her SIgma 18-250, is the best way to walk around. If I had to decide between the two philosophies, it's like, do you want apples or grapes? What mood are you in at the moment?

It's said by the way that the built in OS works better at long focal lengths. I heard from the Sigma guy that the Pentax OS version is being discontinued. From Henries we got our Sigma 18-250 for 399, the OS version was $749, so I would have had to have wanted that OS real bad before I paid the cost of a decent lens for it. And there is no OS made that will save you from needing to use a tripod at 250mm.
06-08-2013, 10:37 AM   #21
Veteran Member
joe.penn's Avatar

Join Date: Mar 2011
Location: Maryland (Right Outside Washington DC)
Photos: Gallery | Albums
Posts: 2,902
QuoteOriginally posted by sumx4182 Quote
You may be right, but I've also hear OS gives you more stops than SR which could potentially be useful at long focal lengths
You are correct - in lens stabilization is better with longer lenses, it also helps quite a bit with framing the image as you won't see the erratic changes in the framing through the viewfinder.

  • 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!
18-250mm, k-mount, pentax, pentax lens, shots, sigma, slr lens, tamron, walk-around
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Similar Threads
Thread Thread Starter Forum Replies Last Post
Sports Battle of the Nations 2012 marekd1111 Post Your Photos! 5 05-04-2012 06:49 PM
Battle Of The Bands - The Two Years War Nowhere Matt General Talk 4 05-07-2011 03:48 AM
Battle of the Pentax Macros malibru Pentax SLR Lens Discussion 20 04-08-2010 02:16 PM
Pick one: battle of the normals Eigengrau Pentax SLR Lens Discussion 45 08-22-2008 11:47 PM
Meet the challenger... Battle of the century! codiac2600 Post Your Photos! 28 08-31-2007 01:03 PM

All times are GMT -7. The time now is 12:28 AM. | 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]