[SSGGeezer]

K50 here. This happens constantly and especially in low light.
I'm about to lose my last nerve here. I shot a low light event/concert. Most pictures are focused wrong.
Lenses are calibrated. Always used single center point.

It feels as if the af point is at least 10x larger than the red dot. I've come to experience, the more vivid and messy the background is the more it tends to focus on the background - like trees, branches. Also, these things really come to light during photoshoots and event photography where every shot counts. I've previously simply dismissed it as a freak accident, lens calibration error or weak technique, but now it's really getting on my nerve.

Also the af feels very unpredictable in low light. I'd say maybe 30% of my pictures are focused correctly.
(No, the AF sensor, mirrors and contacts are not dirty. I've cleaned them many times with 99% alc.)

My next camera is not going to be Pentax, unless they somehow miraculously fix their AF with the K3-III, but as the K1 and KP show, they might not even care about good AF.

Follow what Clackers said to do above^^^^^^.
Lots of good asvice here if you are willing to try.

[labidas]

Follow what Clackers said to do above^^^^^^.
Lots of good asvice here if you are willing to try.

LV is hardly a solution.

[mikesbike]

This is strange. I can say from experience, in the first example I would have had no problem getting a good AF focus on the face here with my K-5 IIs in this situation. In fact, 1 year ago I did just that, with my DA 18-135mm on camera. It was the baptism of some friends' new son. The dad was holding his little baby son over the water basin so the minister could perform the rite. A woman with a high-contrast black & white shirt was standing immediately behind my friend, most of her showing in the frame, while my friend's shirt was a dark blue solid color, then another man behind and to the right. I used center-only spot focus and AF-S. I used the 1/2 press, focused on a my friend's or the baby's face, both of which are sharp, while the lady shown behind, agains whom his profile is set, is softer- as should be the case.

I have not yet tried such a shot with my KP, but nothing of its AF performance has yet suggested anything amiss for me.

It seems the problem shown here might be due to a back-focus issue from a mis-alignment of the AF properties between lens and camera, requiring the camera's fine-tune of the AF with that lens.

I also do a great deal of low-light shooting, and have long done so with a number of Pentax bodies, without issues. Most recently with my KP, and K-S2.

[conradj]

hm. i find myself agreeing with the OP as to the K-P's AF. It seems more picky abt which lenses it likes, compared to the K-7 and K-5. i've a couple lenses including the Tammy 17-50 that it doesn't take to, which the other bodies are fine with.

In very low light with lenses it doesn't like, when i press the AF button often it'll sit and think for an instant before starting up the AF motor. Focus accuracy is more off the wider the lens (and thus the smaller the bits are in the frame that i want it to focus on).

And with these lenses in these low light situations it'll also tend to focus on higher contrast transitions that're not directly under the central spot focus point.

[Ex Finn.]

Following this thread with interest.
Only used my KP with the DA 20-40 ltd and the 150-450 so far and it has not missed a beat.

[conradj]

Just to reiterate: i do test my stuff in low light since i shoot a lot in those conditions. i'm sure it all works much better in daylight ambient conditions.

[clackers]

LV is hardly a solution.

@Labidas, I said no such thing.

Feel free to correct me, but you don't seem to understand either cameras or music photography.

A PDAF system of any brand will latch onto the strongest line under a focus point. It's up to you to make sure it's the target, not the background or foreground - microphones are notorious for getting in the way of a singer's face, at sports events it's fences and signage.

I have used the K-30 (even older than your K-50) and the K-1 for lots of low light events and concerts. Here are my pics, if I can take 'em, you can, but there is a skillset involved which is why forum members like Kenspo are paid to do what they do:

[john5100]

@Labidas, I said no such thing.

Feel free to correct me, but you don't seem to understand either cameras or music photography.

A PDAF system of any brand will latch onto the strongest line under a focus point. It's up to you to make sure it's the target, not the background or foreground - microphones are notorious for getting in the way of a singer's face, at sports events it's fences and signage.

I have used the K-30 (even older than your K-50) and the K-1 for lots of low light events and concerts. Here are my pics, if I can take 'em, you can, but there is a skillset involved which is why forum members like Kenspo are paid to do what they do:

Beautiful shots!!

[felixkh]

@Labidas, I said no such thing.

Feel free to correct me, but you don't seem to understand either cameras or music photography.

A PDAF system of any brand will latch onto the strongest line under a focus point. It's up to you to make sure it's the target, not the background or foreground - microphones are notorious for getting in the way of a singer's face, at sports events it's fences and signage.

I have used the K-30 (even older than your K-50) and the K-1 for lots of low light events and concerts. Here are my pics, if I can take 'em, you can, but there is a skillset involved which is why forum members like Kenspo are paid to do what they do:

Wonderful photos.

[UlrichSchiegg]

Beautiful shots!!

Indeed!!!

[08amczb]

Calckers, I like your shoots!

Now I get used to my KP and I know when should I double check the sharpness. In general I can get good sharp images, but on a wedding, where non repeatable fast things happen, it's a hard work and I can't trust my cameras AF.
I realy like the new open pentax api and the image quality and build quality, and I would never sell my FA limited with my PZ-1p, but when I will switch to full frame I'am considering Nikon and Sony too, not only the K-1/K-1II.

[pts1958]

@Labidas, I said no such thing.

Feel free to correct me, but you don't seem to understand either cameras or music photography.

A PDAF system of any brand will latch onto the strongest line under a focus point. It's up to you to make sure it's the target, not the background or foreground - microphones are notorious for getting in the way of a singer's face, at sports events it's fences and signage.

I have used the K-30 (even older than your K-50) and the K-1 for lots of low light events and concerts. Here are my pics, if I can take 'em, you can, but there is a skillset involved which is why forum members like Kenspo are paid to do what they do:

Belle série, de la compétence !

[SSGGeezer]

Belle série, de la compétence !

Although your sentence is easy to do a rough translation on, the forum rules say that you need to put an English language translation for any foreign language posts.
Proper spelling is optional!

[Ex Finn.]

Give them time.,still stuck with some invasion thing from way back...
they might come around given time.

[pts1958]

Although your sentence is easy to do a rough translation on, the forum rules say that you need to put an English language translation for any foreign language posts.
Proper spelling is optional!

oups : Nice series, skill!