[Edgar_in_Indy]

Here in the US Sigma will calibrate your lens to your camera body if you send both in to them. It's a free service if the Sigma lens is still under warranty. I did it before, and they got the calibration perfect. Sigma's service department in New York is awesome. In my experience, they get the job done quickly and are easy to talk to. I'm not sure how the situation is in Australia though (if that's where you are).

On a side note, it's nice to see more people recognizing that lenses from any manufacturer will often need adjustment. In years past it seemed like a lot of people on here had their heads in the sand and claimed it was mostly only an issue for third-party lenses, or that it meant the lens was defective and needed exchanged. But now that most DSLR's have fine-tuning and Nikon even includes auto-calibration, it seems to be something that people are acknowledging more openly.

[clackers]

Nikon even includes auto-calibration, it seems to be something that people are acknowledging more openly.

Although Nikon don't include any user calibration on their low and mid end bodies, and I'm not sure the Canon Rebels have it either. (thumbdown, yay for Pentax).

[Digitalis]

I'm not sure the Canon Rebels have it either.

They don't.

[Edgar_in_Indy]

Although Nikon don't include any user calibration on their low and mid end bodies, and I'm not sure the Canon Rebels have it either. (thumbdown, yay for Pentax).

Good point. Another example of how Pentax rules when it comes to packing in more features than competing models.

Canon and Nikon can probably get away with it on their lower-end bodies since most of the owners will be people using kit lenses or other lower-end lenses that don't have super thin DOF. And the entry-level users are probably much less likely to even be so discriminating as to notice slight calibration issues, or to attribute it to anything other than just a less-than-ideal shot.

But it is nice to see the issue being addressed openly, and for the manufacturers to be giving users more tools to deal with it, such as lens docks and auto-calibration routines. It seems like I even remember reading something a year or two ago about the newest Canon bodies and lenses having some kind of feedback loop that detects and corrects for calibration mismatches behind the scenes without any user intervention? That would be very cool, if it works.

[rawr]

Although Nikon don't include any user calibration on their low and mid end bodies, and I'm not sure the Canon Rebels have it either.

Note that Nikon DSLR's (or Sony, and also Canon I think) don't even include the option to do pixel mapping in-camera to clean up dead pixels, something even entry-level Pentaxes have had on the menu for ages.

[awscreo]

I'd send the camera in together with the lens. I sent my k1 to Tamron so they calibrated my 70-200 for my lens specifically, and it completely fixed the decentered issue I had. Insure the package though, extra peace of mind

[matroxication]

Agreed. But during the initial conversation prior to sending the lens to them, they did not state anything about sending the camera. only after I called them to confirm if they received the lens, they mentioned about this. Also apart from keeping the camera to capture the moments of my 8 month old daughter, i was bit reluctant to send it via post. When I received the camera, the courier person was literally rotating and playing with the delivery box when i went to collect it even though it was stated as fragile.

[Edgar_in_Indy]

When I received the camera, the courier person was literally rotating and playing with the delivery box when i went to collect it even though it was stated as fragile.

Sounds like somebody needs a fidget spinner!

[matroxication]

I received my Sigma lens from C.R.Kennedy and they stated that they made focus adjustments. When I checked with my K1, the issue is bit worse than before. I was able to get sharp image with distance appx 3 feet if I calibrate my camera to +6 . I now purchased Sigma dock and I need to test this week end. It would help if anyone can share the results of the calibration Sigma 35mm f1.4 art using Sigma dock for Pentax K1. I can use that as a starting point and can calibrate from there. The weird part was from Sigma dock , I cannot see any adjustments and its all set to default. Not sure how the focus adjustment was done though

[clackers]

. It would help if anyone can share the results of the calibration Sigma 35mm f1.4 art using Sigma dock for Pentax K1. I can use that as a starting point and can calibrate from there.

It would not help because back and front focus are due to individual differences in the production lines of both the camera and the lens.

That is, your settings are no good for me and vica versa.

[matroxication]

Thanks Clackers. I completely agree on that part. I came across Dot tune method (

You Tube

You Tube

) to tune the camera autofocus. Not sure if I try that first and then go with the sigma USB dock calibration or not. Since with my Pentax 100mm macro on K1, am getting soft focus at infinity range and wide open.

[MadMathMind]

This is my recommendation as well, however I also recommend a suitable focus calibration target such as the Lens align. This is to ensure accurate and repeatable results when calibrating lenses.

My recommendation is to not buy Sigma lenses. I know it does hurt K-mount for choices but man...those things are just so quirky on Pentax bodies. I think they might be as well on others but maybe people just don't notice? (TBH, using a Canon body to shoot Sigma lenses strikes me as getting the worst of both worlds, since Canon lenses are great and their bodies mediocre but...)

[Paul the Sunman]

My recommendation is to not buy Sigma lenses.

I think that's going a bit far. My 35mm f/1.4 Art works perfectly on my K1, and my son's 50-500 Bigma is just great on the K3 and K1. I wish Sigma produced more lenses in K-mount.

I was also very impressed that they replaced to mount free of charge due to the K1 scratching problem.

[matroxication]

Finally got some positive results with the AF. I used the sigma USB dock to calibrate the lens at 0.6m to -2 but still I was not able to get consistent results in that distance. Instead of calibrating the lens in Infinity range, I followed the Dot Tune method and it worked perfect. I calibrated my AF tune setting in K1 to +1 as per that method and then I was able to nail the focus in every distance. I should have tried the DOT Tune method before purchasing the Sigma USB dock.
But anyway, the issue is now resolved and thanks everyone for the support. Am going to try DOT tune method on my 100mm 2.8 macro and see how it performs.

[tlwyse]

Just went through a couple days of AF focus adjustments for my 28-105, Sigma 35mm and rented 15-30mm and 24-70mm lenses.

I've done this exercise for several bodies in the past (using a LensAlign and FocusTune software) and usually find there's a global adjustment for the body that applies to all lenses.

In my latest test with my brand new K1, I found all the Pentax lenses needed about a -2 to -4 adjustment. The Sigma 35mm was the odd lens out as it needed about +2.

Other comments:
The Sigma 35mm f/1.4 Art lens is really nice and sharp...but I found the other lens, espcially the 15-30 and 24-70 to be pretty close. The 15-30 is an exceptional ultra-wide zoom and probably will be my next purchase. The 28-105 actually performed better than I thought but it's simply not a fast lens of course. The 28-105 performed well enough that I'll probably sell off my Sigma 85 1.4 and 50 1.4 lenses.

So far, coming from a K3, I'm really enjoying the K1.

Terry