Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
09-24-2015, 04:28 PM   #1
Junior Member




Join Date: Nov 2012
Posts: 38
Focus hesitation

A quick question if I may. I have the K-3 and only the DA 50mm f1.8 right now so I can't compare with other lenses. But anyhow, I was just wondering, it seems like when I try to focus on a less contrasty subject, the focus pauses a split second before activating. If it's any other subject, it reacts immediately. Just wanted to know if this is normal operation? And is it a camera or lens thing? Thanks!

09-24-2015, 04:34 PM   #2
Administrator
Site Webmaster
Adam's Avatar

Join Date: Sep 2006
Location: Arizona
Photos: Gallery | Albums
Posts: 43,137
QuoteOriginally posted by thehiko Quote
A quick question if I may. I have the K-3 and only the DA 50mm f1.8 right now so I can't compare with other lenses. But anyhow, I was just wondering, it seems like when I try to focus on a less contrasty subject, the focus pauses a split second before activating. If it's any other subject, it reacts immediately. Just wanted to know if this is normal operation? And is it a camera or lens thing? Thanks!
It's indeed normal if there's low contrast or low light. The tougher the conditions the slower the overall focusing speed will be.

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:

09-24-2015, 04:50 PM   #3
Junior Member




Join Date: Nov 2012
Posts: 38
Original Poster
Hi thanks for the quick response. After posting, I realized I could have worded it better. I understand that low contrast scenes are definitely harder for the camera. However, the actual reaction of getting the AF started is delayed is what I meant.

So for easy focus targets:
Press AF button - Camera starts focus ---- Finish focus

Hard targets:
Press AF button ------- Camera starts focus -------------- Finish focus

Dashes indicate time or delay.
09-24-2015, 06:43 PM   #4
Site Supporter
ramseybuckeye's Avatar

Join Date: Apr 2009
Location: Elida, Ohio
Photos: Gallery | Albums
Posts: 8,622
This is a guess, but I think the focus actually starts before you hear the screw drive, the screw drive is just moving the lens to the focus position. I don't really think the screw drive changes speed at all, it just depends on the distance the lens moves from the start position to the desired focus position.

09-24-2015, 07:07 PM   #5
Junior Member




Join Date: Nov 2012
Posts: 38
Original Poster
QuoteOriginally posted by ramseybuckeye Quote
This is a guess, but I think the focus actually starts before you hear the screw drive, the screw drive is just moving the lens to the focus position. I don't really think the screw drive changes speed at all, it just depends on the distance the lens moves from the start position to the desired focus position.
Hmm well, the thing is that the red AF point in the viewfinder doesn't come on immediately either. So referring to my examples above, for scenario 1, I hold the AF button, then immediately the AF point lights up and the lens starts to focus. In scenario 2, I hold the AF button, but nothing happens for about 0.2 seconds, then the red focus point lights up and initiates the AF. It's almost as if the camera is spending some time evaluating whether or not it needs to start focusing. If what you stated is true, I'd assume the AF point would still light up immediately?

I just want to make sure that this isn't abnormal, and also if it seems body or lens dependent. Thanks!
09-24-2015, 11:05 PM   #6
Site Supporter
jatrax's Avatar

Join Date: May 2010
Location: Oregon
Photos: Gallery | Albums
Posts: 10,770
Are you using multiple af points? If so perhaps the delay is the camera choosing which point to actually use. Try single counterpoint and see if the behavior changes. Just speculating.
09-25-2015, 02:14 AM   #7
Junior Member




Join Date: Nov 2012
Posts: 38
Original Poster
QuoteOriginally posted by jatrax Quote
Are you using multiple af points? If so perhaps the delay is the camera choosing which point to actually use. Try single counterpoint and see if the behavior changes. Just speculating.
I am using the single point focus SEL 1.
09-25-2015, 07:58 AM   #8
Junior Member




Join Date: Nov 2012
Posts: 38
Original Poster
Ok so quick update...the red focus lamp does come on immediately but the actual focus doesn't get started right away. So in that sense, ramseybuckeye's description makes sense. Soooo the camera is getting started with the focus but just evaluating before moving the lens because of the scene I guess. I think the focus process is initiated before the lens moves so I will accept that as normal.

I am very sorry for the wrong description of the issue! Embarrassing and complete noob of me to do that... No more worrying, will just shoot!

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!
dslr, focus, k-3, k3, pentax k-3, subject
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Focus, Focus, Focus (or the usefulness of focus charts) GoremanX Pentax DSLR Discussion 31 12-21-2014 11:49 AM
Weekly Challenge Winners - PROJECT 52-6-33- FOCUS- Out of focus jcdoss Weekly Photo Challenges 13 10-08-2014 09:06 PM
Project 52 PROJECT 52-6-33- FOCUS- Out of focus noelcmn Weekly Photo Challenges 15 10-07-2014 02:14 PM
Focus calibration - who to believe?! (hex or focus screen) heartattackandvine Troubleshooting and Beginner Help 14 12-05-2013 01:34 AM
Macro Hesitation..... eaglem Post Your Photos! 2 07-15-2013 08:42 PM



All times are GMT -7. The time now is 10:16 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