[Barrington]

Something I've never done and really only just become aware of . I'm expecting my new K-70 and 50mm f1.8 today or tomorrow , is calibrating something I need to do or check ?

Thanks

[Unregistered User 8]

Something I've never done and really only just become aware of . I'm expecting my new K-70 and 50mm f1.8 today or tomorrow , is calibrating something I need to do or check ?

Thanks

It is worth a check.

Fixing Front and Back Focus - Introduction - In-Depth Articles

[SharkyCA]

Something I've never done and really only just become aware of . I'm expecting my new K-70 and 50mm f1.8 today or tomorrow , is calibrating something I need to do or check ?

Thanks

Here is a couple of articles on lens alignment/focus:How To Calibrate Your Lenses | A Simple Fix For Blurry Images (2019 Update)
https://photographylife.com/how-to-quickly-test-your-dslr-for-autofocus-issues
https://photographylife.com/how-to-calibrate-lenses

[K(s)evin]

Get out and enjoy your new gear! Take lots of photos in order to familiarize yourself with the camera. Make sure that your technique is solid. Ask lots of questions here on the forum. And don't worry about lens calibration right away. If, after taking lots of photos and finding a consistent problem with getting in-focus results, then consider calibration. Inquire here about proper testing methods. But beware. Make absolutely sure that you understand how Pentax AF is supposed to work. Be confident in your shooting technique.
In 10 years of shooting with 5 different models of Pentax DSLR, and too many lenses to count, I have yet to calibrate a single lens. Maybe I've just been lucky. I don't know. Just try to be sure that you have eliminated any other possible cause.

[cport]

Barrington: Making pictures should be fun! So take your new equipment and enjoy it.


I have been shooting with Pentax cameras and lenses for more than 12 years (approx 5 cameras, 20 lenses) and I have never needed any lens calibration. Once I let my new camera AF system calibrate.

[Barrington]

Thanks guys , in my OP when I said I hadn't been really aware of calibration it was only when I was researching lenses for my K-70 I came across it , so I thought I'd ask .

---------- Post added 04-26-19 at 01:51 PM ----------

Oh btw the camera & lens have arrived , currently charging the battery

[stevebrot]

Thanks guys , in my OP when I said I hadn't been really aware of calibration

While your camera has an AF fine adjust feature (it is the camera that is adjusted, not the lens), the process of doing so can be tedious. I vote with those above who suggest getting out and enjoying your new kit. If there are problems with persistent missed focus, such will be apparent in the first few days of use.

Have fun!


Steve

[pschlute]

Whilst i agree with those who say get out and start taking pictures, there is a place for camera/lens calibration.

Fine adjustment of AF began to appear in cameras as the megapixels of our sensors got more numerous and we were able to see detail that was not possible in early digital or before that film cameras. Basically the shortcomings of the Phase-Detect autofocus systems (viewfinder method) were revealed. PDAF tolerances when built at the factory can vary, and the accuracy of the system is not 100%. (Live View is not affected as the focus is done directly on the sensor itself.)

My K-1 was not giving me what I wanted when I first purchased it, and never having had a AF/FA system in a camera before I was stumped. i need to adjust +8 on average to achieve perfect AF behaviour with my lenses. It will vary by camera, so if the OP does feel that his pictures are not as sharp as they should be when viewed at 100%, there is an easy solution.

[Barrington]

i need to adjust +8 on average to achieve perfect AF behaviour with my lenses.

Hi Peter , where is that adjustment found ?

Ok I've found it

Alternative method, clever, but I think I'll stick with my own.

You Tube

You Tube

My method is to lay a 4' ruler at an (~=45 degree) angle against something solid in a well-illuminated place, move the camera back a ways (paying attention to the range of any zoom values and the minimum focusing distance) and take pictures of a particular point on the ruler (which I usually mark with a black binder clip). I set the aperture somewhere in the center of the range for the lens being tested, figuring that's where the least distortion will occur. I take four pictures, two with manual focus through the viewfinder, and two with autofocus through the viewfinder. Two of each because I rotate the focus ring all the way to the left for one before refocusing, and the other all the way to the right. Then I can see the range of what's in-focus on the ruler, and adjust the camera based on my estimate of what it'll take to get the center of that range to where the paper clip is, repeating the process as necessary. Two or three tries is generally sufficient.

[psoo]

If you calibrate a lens that needs it, don't you have to recalibrate all the others that didn't need it? What a mess.

[miv]

If you calibrate a lens that needs it, don't you have to recalibrate all the others that didn't need it? What a mess.

That's not a problem. k-70 can remember settings for up to 20 individual lenses.

If you calibrate a lens that needs it, don't you have to recalibrate all the others that didn't need it? What a mess.

No, the camera remembers each lens by data that the little computer inside the lens sends to the camera, as long as you select the option for setting them individually, as opposed to the "do'em all the same way" option.

By the way, something I found interesting about Canon EOS cameras: Pentax has one setting for each lens, so with zoom lenses, you're supposed to pick a point in the middle of the range and calibrate at that midpoint. What I've been doing is calibrating at each extreme and interpolating between the two settings to optimize the midpoint setting. What the Canon cameras do is have you calibrate at each extreme, and it remembers two settings for each zoom lens, and interpolates between the two for any given point in between. Pretty clever.

[psoo]

Thanks miv and dlh, it's great that no recalibration is needed. Smart camera!

I think I figured out why they put an unnecessary and unusable second foot attachment ring in the case with the lens. In my description of the problem, I'd stated that I'd tried to pick the lens up by its foot, when the lens fell apart. I suspect they're going to argue that my complaint was about the foot, not the overtightened internal screws. They're going to say they fixed it by replacing the foot and cover up the stuff about the parts damaged during original assembly of the lens. My guess is that there's no documentation about exactly what they did do to repair the lens other than replacing the foot; which leads to even more questions: did they charge me for replacing that part unnecessarily, and how is it that it costs more than six hundred bucks to replace that one part? If that's all they claim to have done, and the thing is obviously in good shape (they sent it back to me, after all, with no evidence or documentation to suggest that there was anything wrong with it), why did they do anything to the lens at all?