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zapp · 10-17-2016, 11:48 AM

My 24-70 showed mixed/different results for 24 and 70 mm. I decided to calibrate for 70 mm at the end. Stopping down the 24 side one stop will cover up all issues.
There was something like 6 steps between both ends.

Btw a tele lens may have a narrow DOF that requires optimum placmenet, but the amount of barrel movement from close to far focus is fairly wide. A wide angle lens requires much less truning to go from close to far focus huts in absolute terms a small misalignemnt of lens elements in the back is more significant than for a tele lens.

jls74d00 · 10-25-2016, 03:23 PM

What are the best methods for testing autofocus accuracy?

DimC · 10-29-2016, 04:55 AM

Originally posted by jls74d00

What are the best methods for testing autofocus accuracy?

I've been using this method for a while on all my Body/lens combination, works well.
AF microadjustment for the 1Ds mark III, 1D Mk3, 5D Mk2, 7D, 1D X

**UncleVanya** · 10-29-2016, 09:50 AM

Originally posted by DimC

I've been using this method for a while on all my Body/lens combination, works well.
AF microadjustment for the 1Ds mark III, 1D Mk3, 5D Mk2, 7D, 1D X

I can't imagine being 50x the distance of your 300mm lens from the screen inside our house.

DimC · 10-29-2016, 10:19 AM

Originally posted by UncleVanya

I can't imagine being 50x the distance of your 300mm lens from the screen inside our house.

Ha-Ha true !

It's 5X not 50x, which is still a long distance I agree. But for my 70-200mm I found out a way to to have 7-8m and it was fine.

**UncleVanya** · 10-29-2016, 12:18 PM

Originally posted by DimC

Ha-Ha true !

It's 5X not 50x, which is still a long distance I agree. But for my 70-200mm I found out a way to to have 7-8m and it was fine.

No. it is 50x and some people use 30x.

Quote:

Note - Camera-to-subject distance should ideally be no less than 50 times the focal length of the lens. For a 50mm lens, that would be at least 2.5 meters (25m for a 500mm)

10m is 50x on a 200mm lens. At 7-8m that is over 30xso that should work fine.

DimC · 10-29-2016, 01:22 PM

Yeah right !

I had no problem calibrating my lenses with that method, which is fairly simple.

Lampo · 12-09-2016, 02:12 AM - **1 Like**

I have been doing several tests, but in the end decided to sent the K-1 for calibration. I was not getting the pictures I got from my K-5 IIs, which I expected to be at least the case. The amount of keepers was so low, I started to doubt my skills and became frustrated that I could not get a single worthwhile shot, while there is a thread here that has the most amazing shots. My shots were out of focus and even with SR turned on and 1/160 shutter time, I would get motion blur shooting with the 24-70...

The good news is, that my Pentax dealer is tremendously good, so I have handed in my Pentax K-1 and received another K-1 so I would not be without a camera! And this K-1 is a complete different experience! I get tack sharp photo's, even on my first outing when I did not even bother to calibrate my lenses on the K-1. Seagulls scaled to 100% are almost as sharp as the image I would get from my K-5 IIs!! I am loving this camera!

So now I hope that my own K-1 will return from Pentax and behave just like this one does!

carolina_sky · 12-09-2016, 08:40 AM

You have a good dealer! I don't think my local pentax dealer even knows how to spell K-1.

Lampo · 12-13-2016, 11:46 AM

I certainly have a good dealer, it is just a small shop with the owner helping you, makes everything much more personal, which I highly appreciate! Today I got a call from the owner, my K-1 is back from Pentax and the CCD sensor is replaced, the original one was not functioning properly. He will conduct now some tests to assess the sharpness before I am allowed to pick it up ;-).

I am so happy with this outcome!

crash82 · 12-03-2018, 03:46 PM

DFA* 50 1.4: +8
DFA* 70-200 2.8: +8

Should i send it back for calibration (under warranty)? Also the grip ralltes a little bit.

pschlute · 12-03-2018, 04:11 PM

Originally posted by crash82

DFA* 50 1.4: +8
DFA* 70-200 2.8: +8

Should i send it back for calibration (under warranty)? Also the grip ralltes a little bit.

Why? You able to adjust within the tolerance.

10-29-2016, 12:18 PM	#36
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,477	Originally posted by DimC Ha-Ha true ! It's 5X not 50x, which is still a long distance I agree. But for my 70-200mm I found out a way to to have 7-8m and it was fine. No. it is 50x and some people use 30x. Quote: Note - Camera-to-subject distance should ideally be no less than 50 times the focal length of the lens. For a 50mm lens, that would be at least 2.5 meters (25m for a 500mm) 10m is 50x on a 200mm lens. At 7-8m that is over 30xso that should work fine. Last edited by UncleVanya; 10-29-2016 at 12:28 PM.

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10-17-2016, 11:48 AM	#31
zapp Pentaxian Join Date: Jul 2011 Posts: 2,389	My 24-70 showed mixed/different results for 24 and 70 mm. I decided to calibrate for 70 mm at the end. Stopping down the 24 side one stop will cover up all issues. There was something like 6 steps between both ends. Btw a tele lens may have a narrow DOF that requires optimum placmenet, but the amount of barrel movement from close to far focus is fairly wide. A wide angle lens requires much less truning to go from close to far focus huts in absolute terms a small misalignemnt of lens elements in the back is more significant than for a tele lens.

10-25-2016, 03:23 PM	#32
jls74d00 Forum Member Join Date: Jan 2013 Location: Tacoma, WA Posts: 60	What are the best methods for testing autofocus accuracy?

10-29-2016, 04:55 AM	#33
DimC Veteran Member Join Date: Jul 2012 Location: Paris Photos: Gallery \| Albums Posts: 813	Originally posted by jls74d00 What are the best methods for testing autofocus accuracy? I've been using this method for a while on all my Body/lens combination, works well. AF microadjustment for the 1Ds mark III, 1D Mk3, 5D Mk2, 7D, 1D X

10-29-2016, 09:50 AM	#34
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,477	Originally posted by DimC I've been using this method for a while on all my Body/lens combination, works well. AF microadjustment for the 1Ds mark III, 1D Mk3, 5D Mk2, 7D, 1D X I can't imagine being 50x the distance of your 300mm lens from the screen inside our house.

10-29-2016, 10:19 AM	#35
DimC Veteran Member Join Date: Jul 2012 Location: Paris Photos: Gallery \| Albums Posts: 813	Originally posted by UncleVanya I can't imagine being 50x the distance of your 300mm lens from the screen inside our house. Ha-Ha true ! It's 5X not 50x, which is still a long distance I agree. But for my 70-200mm I found out a way to to have 7-8m and it was fine.

10-29-2016, 01:22 PM	#37
DimC Veteran Member Join Date: Jul 2012 Location: Paris Photos: Gallery \| Albums Posts: 813	Yeah right ! I had no problem calibrating my lenses with that method, which is fairly simple.

12-09-2016, 02:12 AM - 1 Like	#38
Lampo Forum Member Join Date: Aug 2010 Location: Leiden Posts: 59 Original Poster	I have been doing several tests, but in the end decided to sent the K-1 for calibration. I was not getting the pictures I got from my K-5 IIs, which I expected to be at least the case. The amount of keepers was so low, I started to doubt my skills and became frustrated that I could not get a single worthwhile shot, while there is a thread here that has the most amazing shots. My shots were out of focus and even with SR turned on and 1/160 shutter time, I would get motion blur shooting with the 24-70... The good news is, that my Pentax dealer is tremendously good, so I have handed in my Pentax K-1 and received another K-1 so I would not be without a camera! And this K-1 is a complete different experience! I get tack sharp photo's, even on my first outing when I did not even bother to calibrate my lenses on the K-1. Seagulls scaled to 100% are almost as sharp as the image I would get from my K-5 IIs!! I am loving this camera! So now I hope that my own K-1 will return from Pentax and behave just like this one does!

12-09-2016, 08:40 AM	#39
carolina_sky Site Supporter Join Date: Nov 2013 Photos: Gallery Posts: 156	You have a good dealer! I don't think my local pentax dealer even knows how to spell K-1.

12-13-2016, 11:46 AM	#40
Lampo Forum Member Join Date: Aug 2010 Location: Leiden Posts: 59 Original Poster	I certainly have a good dealer, it is just a small shop with the owner helping you, makes everything much more personal, which I highly appreciate! Today I got a call from the owner, my K-1 is back from Pentax and the CCD sensor is replaced, the original one was not functioning properly. He will conduct now some tests to assess the sharpness before I am allowed to pick it up ;-). I am so happy with this outcome!

12-03-2018, 03:46 PM	#41
crash82 New Member Join Date: Jul 2018 Posts: 15	DFA* 50 1.4: +8 DFA* 70-200 2.8: +8 Should i send it back for calibration (under warranty)? Also the grip ralltes a little bit.

12-03-2018, 04:11 PM	#42
pschlute Moderator Loyal Site Supporter Join Date: Mar 2007 Location: Surrey, UK Photos: Gallery Posts: 8,223	Originally posted by crash82 DFA* 50 1.4: +8 DFA* 70-200 2.8: +8 Should i send it back for calibration (under warranty)? Also the grip ralltes a little bit. Why? You able to adjust within the tolerance.

Did you have to fine adjust the focus on your K-1?

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