Originally posted by audiobomber What AF point(s) active in AF-S? I would only use the Center Point for birds in trees.
Have you tried using AF Adjust? I've had trouble with primes locking in the past due to front/back focus. Adjusting focus resolved the issue.
I have done AF adjudtment, over a longer period of time it has settled on -2 for the DA560, and -3 for the DA560+ 1.4tc.
I normally only use centre point s-af, because I will mostly apply a certain amount of cropping afterwards anyway.
I don't actually have a problem getting either the DA560 or the combo with tc1.4 to lock focus, especially the combo has better AF than I initially expected. The problem is the lack of reliable consistency and the lack of a certain amount of discrimination of the precise subject you want to lock onto. I cannot really see the lens or the lens motor as the cause of this, but perhaps I am wrong.
Sometimes I am hiking, lift the camera and want to focus, and what I am looking for, is a camera that will simply start AF immediately and lock, period. What I get with the K3/DA560, is that I half press the shutter button, and often it initially just stutters a bit, and goes back and forth some, or even needs multiple half presses before even starting the focus travel, and I typically need several attempts before I get it to focus on the bird, even when it is a clearly isolated subject.
I don't so much care about actual speed in ms. but I am getting to a point where I am not enjoying shooting the Pentax setup any longer, because birds don't give you time to fiddle with your auto focus. I am only interested in a future Pentax camera that reacts immediately when I lift the camera and half press the shutter button, singles out the subject, also smaller subjects, and locks focus accurately, and decisively. If the KP can give me that, I am in, or the possible K3 successor. If it on the other hand also resorts to stuttering, need of pampering, searching for the subject while you have the active AF point exactly on it, then it is time for me to switch to the new Sigma 500/4 and Nikon D500/7200.
I would rather stay with the Pentax though, obviously because of cost, but also because it otherwise fits my needs. It is a bit of a grey area, because I could see better AF programming and especially a better, more reliable processor giving me what I need. The K3 processor is suspect in my book anyway, having had the mirror flapping and locking up on several occasions.
Chris
---------- Post added 11-13-17 at 11:49 AM ----------
Originally posted by stevebrot It is my recollections as well that there was some sort of improvement in the AF in the K-3II over the K-3, but have been unable to find any documentation of different AF module hardware in reviews, the official specs, or Web site promotional materials.
- All three (K-3, K-3II, and KP) have SAFOX 11 27 point with 25 cross-point.
- AF firmware improvements were made for the K-3II for faster AF-C in general as well as AF-S with a selection lenses:
- HD PENTAX-D FA★70-200mmF2.8ED DC AW
- HD PENTAX-D FA 150-450mmF4.5-5.6ED DC AW
- HD PENTAX-DA 18-50mmF4-5.6 DC WR RE
- New AF firmware improvements are claimed for the KP
- All three have three (3) f/2.8-tuned AF points in the center column
- All three are spec'd with the same claimed low light (-3 EV) capability
- The detailed review of the KP on this site indicated a substantial improvement in tracking performance over the K-3 and better overall AF than the K-3
Given that the DA 560/5.6 is not known for its AF speed, I have my doubts that the KP would provide the boost that the OP desires.
See my answer to audiobomber
Chris