Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
04-04-2011, 03:15 PM   #1
Junior Member
testdasi's Avatar

Join Date: Mar 2011
Location: London
Posts: 35
Long, AF and light?

Is there any lens out there that can satisfy the following 3 conditions?
  1. Autofocus
  2. Focal length above 300mm (if zoom, focal length of long end above 300mm)
  3. Weight no more than 750g without hood

The reason for 2 is that I already bought the Tamron 70-300 f4-5.6 so would like to know if there is anything longer out there.
The reason for 3 is so that the lens balances on the K-5 without the need of a grip. Plus I don't want to go to the gym for every photo session.

I'm pretty sure there are some options out there satisfying 1 and 2.

But adding 3 makes it tricky.

04-04-2011, 03:36 PM   #2
Veteran Member




Join Date: Mar 2010
Photos: Gallery | Albums
Posts: 1,545
Yeah, the infamous Bigma wouldn't satisfy qualification 3.
04-04-2011, 03:55 PM   #3
Administrator
Site Webmaster
Adam's Avatar

Join Date: Sep 2006
Location: Arizona
Photos: Gallery | Albums
Posts: 40,984
It exists!

SMC Pentax-FA 80-320mm F4.5-5.6 Reviews - Pentax Lens Reviews & Pentax Lens Database

Adam
PentaxForums.com Webmaster (Site Usage Guide | Site Help | My Photography)



PentaxForums.com's high server and development costs are user-supported. You can help cover those costs by donating. Or, buy your photo gear from our affiliates, Adorama, B&H Photo, or Topaz Labs, and get FREE Marketplace access - click here to see how! Trusted Pentax retailers:

04-04-2011, 06:56 PM   #4
Ash
Community Manager
Loyal Site Supporter
Ash's Avatar

Join Date: Mar 2007
Location: Toowoomba, Queensland
Photos: Gallery | Albums
Posts: 22,679
Other than Adam's suggestion, which has ordinary IQ, you will find that conditions 2 and 3 are most difficult to satisfy together. The nature of telephoto lenses are that they require a lot more glass elements and physical size (particularly length) to be able to attain the magnifications of the order of 300+ mm with adequate IQ to be useful.

04-05-2011, 12:50 AM   #5
Junior Member
testdasi's Avatar

Join Date: Mar 2011
Location: London
Posts: 35
Original Poster
Wow! 20mm longer than the Tamron! And the equivalent focal length matches the long end of my FZ28. What coincidence.

QuoteOriginally posted by Ash Quote
Other than Adam's suggestion, which has ordinary IQ, you will find that conditions 2 and 3 are most difficult to satisfy together. The nature of telephoto lenses are that they require a lot more glass elements and physical size (particularly length) to be able to attain the magnifications of the order of 300+ mm with adequate IQ to be useful.
Precisely why I asked. I was very interested in the Bigma but was turned off by the weight. Seems like 320mm is the limit for that weight class.
04-05-2011, 02:32 AM   #6
Pentaxian




Join Date: Jul 2010
Location: Lyngby, Copenhagen
Photos: Albums
Posts: 742
As a curiosity, there is a minolta/sony 500mm mirror lens with autofocus. It's probably pretty light. But then you'd have to get a sony dslr to go with it.

Regards,
--Anders.
04-05-2011, 05:35 AM   #7
Senior Member




Join Date: Aug 2009
Location: Melbourne, Victoria.
Photos: Gallery
Posts: 113
Testdasi the lens you seek is the Tokina ATX 80-400, tick 1, tick2, almost tick 3.
04-05-2011, 07:48 AM   #8
Pentaxian




Join Date: Aug 2007
Photos: Gallery
Posts: 1,563
This will do 2 out of 3 as well:
Amazon.com: Opteka 500mm / 1000mm High Definition Mirror Telephoto Lens for Pentax K-5, K-R, K-X, K-7, K-2000 & K20D Digital SLR Cameras: Camera & Photo

Cheers, Bert

04-05-2011, 08:10 AM   #9
Veteran Member
dgaies's Avatar

Join Date: Oct 2009
Location: Maryland / Washington DC
Posts: 3,917
QuoteOriginally posted by DreTAX Quote
Testdasi the lens you seek is the Tokina ATX 80-400, tick 1, tick2, almost tick 3.
The 80-400 is probably a good option to consider. I can't think of another lens that comes closer to meeting all three requirements (80-320 aside).
04-05-2011, 10:16 AM   #10
Veteran Member




Join Date: Mar 2007
Location: Boston, PRofMA
Photos: Albums
Posts: 3,053
I want one that 600mm, but the size of a pencil :-)

You're fighting physics...longer range = more glass generally (assuming you care about image quality) = more weight...
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, camera, dslr, k-5, k-5 ii, k-5 iis, k5, length, lens, pentax k-5, reason
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Something light and long for a K-x Tord Ask B&H Photo! 7 01-27-2011 04:20 AM
How long will fresh batteries last in long exposure? tnis0612 Troubleshooting and Beginner Help 6 05-18-2010 09:11 AM
Night Light Flight (Sandhill Cranes made of light) ifringe Post Your Photos! 2 12-30-2009 06:53 PM
pick two long,fast,light txsbluesguy Photographic Technique 13 04-21-2009 08:49 PM
Poll...how long is long enough for images? FHPhotographer Photo Critique 5 04-12-2009 02:30 PM



All times are GMT -7. The time now is 02:19 AM. | 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