Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
09-10-2017, 02:27 PM   #1
Forum Member
pentax360's Avatar

Join Date: Jan 2016
Location: OR
Posts: 86
Another image stabilization question.

Do KAF zoom lenses communicate their current focal length to the camera?

Will IS on KAF lenses that arenít on the start up ďfocal length input listĒ work optimally.
Iím specifically looking at a KAF 90mm, and if it were K/KA I would only be able to select 85-100mm, which the IS would work but not optimally.


Iím sure this would be self-evident if I had any KAF lenses, but currently all mine are K and KA. (spent a total of $66 on my 3 lenses )


thanks.

09-10-2017, 02:39 PM   #2
Administrator
Site Webmaster
Adam's Avatar

Join Date: Sep 2006
Location: Arizona
Photos: Gallery | Albums
Posts: 47,036
QuoteOriginally posted by pentax360 Quote
Do KAF zoom lenses communicate their current focal length to the camera?
Yes and yes, anything with AF does.

Are you talking about the Tamron 90mm?

Also, you probably wouldn't be able to tell a difference even if the camera thought it was an 85mm. SR will still work well.

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



PentaxForums.com server and development costs are user-supported. You can help cover these 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:

09-10-2017, 02:44 PM   #3
Otis Memorial Pentaxian
Loyal Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 30,082
QuoteOriginally posted by pentax360 Quote
Do KAF zoom lenses communicate their current focal length to the camera?
The interface supports focal length update, but whether a particular lens supports the feature and how granular that support is varies by lens and maker.

QuoteOriginally posted by pentax360 Quote
Will IS on KAF lenses that aren’t on the start up “focal length input list” work optimally.
Edit: Most lenses will report actual focal length and the camera will act appropriately.* For non-AF lenses, convention is to choose the next lowest focal length and not worry about whether the performance is optimal. I enter 85mm for my manual focus Tamron 90/2.8 (72B) and it works fine.


Steve

* Example: My FA 77/1.8 reports as 77mm and SR behavior is normal.

Last edited by stevebrot; 09-10-2017 at 02:50 PM.
09-10-2017, 03:40 PM   #4
Forum Member
pentax360's Avatar

Join Date: Jan 2016
Location: OR
Posts: 86
Original Poster
Thanks a lot, just what I needed to know.

QuoteOriginally posted by Adam Quote
-

Are you talking about the Tamron 90mm?
Yes I am.
---------------------------

QuoteOriginally posted by stevebrot Quote
The interface supports focal length update, but whether a particular lens supports the feature and how granular that support is varies by lens and maker.
What kind of wording would I look for to make sure a zoom lens can do focal length update?
Are there very many lenses that don't do it?

Thanks.

09-10-2017, 09:07 PM   #5
Administrator
Site Webmaster
Adam's Avatar

Join Date: Sep 2006
Location: Arizona
Photos: Gallery | Albums
Posts: 47,036
QuoteOriginally posted by pentax360 Quote
Are there very many lenses that don't do it?
As long as they are autofocus, they will automatically update. Manual focus lenses won't.

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



PentaxForums.com server and development costs are user-supported. You can help cover these 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:

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!
camera, dslr, image stabilization, kaf, length, lenses, photography
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Image stabilization with focal length that isn't on the list? pentax360 Pentax DSLR Discussion 4 08-13-2017 12:11 AM
Lens Stabilization VS Camera Stabilization philbaum Non-Pentax Cameras: Canon, Nikon, etc. 17 10-14-2015 12:38 PM
Generic question about image stabilization feature frascati Non-Pentax Cameras: Canon, Nikon, etc. 2 03-27-2014 03:18 PM
Newbie Image Stabilization question Clavius Troubleshooting and Beginner Help 15 02-20-2011 11:46 AM
In-body stabilization + lens stabilization ntx Troubleshooting and Beginner Help 14 02-24-2009 05:24 PM



All times are GMT -7. The time now is 11:36 PM. | See also: NikonForums.com, CanonForums.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