K-5 auto focus fine adjustment tools?

Sten · 03-19-2011, 07:15 AM

I am new to Pentax, and I have a K-5 and the Pentax 18-135 lens.
I am considering auto focus fine adjustment, not because I have seen any need for it - I am just curious if my lens focuses exactly right.
Now there are many tools around on Internet, both free and for a charge.
What tools are the best of these two kinds?

Sten

Acheron · 03-19-2011, 10:16 AM - **1 Like**

Here is a link to pdf which is very useful
http://focustestchart.com/focus10.pdf

Sten · 03-19-2011, 11:59 PM

Acheron,
Thank you very much!
The document is quite interesting, and I will try this method.

Sten

pop4 · 03-20-2011, 12:45 AM

I tend to use the techniques on this page instead: AF microadjustment for the 1Ds mark III, 1D Mk3, 5D Mk2, 7D

**StigVidar** · 03-20-2011, 04:11 AM

You could also take a photo at 135mm f/5,6 of a curbstone at the other side of a road. It is then easy to see if there is front or back focusing.

Sten · 03-20-2011, 09:03 AM

Originally posted by StigVidar

You could also take a photo at 135mm f/5,6 of a curbstone at the other side of a road. It is then easy to see if there is front or back focusing.

Thank you, StigVidar!

I tried your method first, because only minutes after I read about it, my wife took me out for a walk.

I then took pictures of a parking lot covered with small concrete squares, after placing two pencils of different colours at the same distance to focus on. The edges of the concrete squares provided a scale which should be most at focus where the pencils were. As you suggested, I used 135 mm/5.6, and had my camera at various distances from the pencils.
Looking at the pictures at home in my computer, I got a rough indication that my lens/camera combination focuses well.

Pros of this method: very easy and quick to use.
Cons: If you want a more exact measurement, then you should use a more sophisticated method as a complement.

Sten

Sten · 03-20-2011, 09:12 AM

Originally posted by Acheron

Here is a link to pdf which is very useful
http://focustestchart.com/focus10.pdf

Acheron,

Thank you so much!
I used your method, and I found it to be the best for me.
Furthermore, it showed that my camera/lens combination focuses spot-on without any adjustment, actually better than the example in the instructions of your method. So I am quite happy.

Pros of this method: The method is reliable and gives significant results, which you can check afterwards in your computer. The instructions are clear and complete.
Cons: There is some easy scissor cutting and glueing, and you should use the right amount of glue (too much makes the paper bulge a little).

Sten

Last edited by Sten; 03-20-2011 at 10:45 AM.

Sten · 03-20-2011, 09:25 AM

Originally posted by pop4

I tend to use the techniques on this page instead: AF microadjustment for the 1Ds mark III, 1D Mk3, 5D Mk2, 7D

Pop4,

Thank you very much!
I tried your method, and it indicated that my camera/lens combination focuses well.

Pros of this method: Easy to use, focusing on an image on your computer screen.
Cons:
- It can be difficult to achieve the ideal camera-to-subject distance of 50 times the focal length of the lens, in my case 50x135 mm = 6.75 meters. I used a couple of meters which was within the limits of the room.
- It is hard to ensure that the computer screen is exactly square on and lined up with the camera.
- You need to be observant in order to see if the lens focusing ring moves or not, when you press the shutter to auto focus.
- The instructions could me more clear.

Sorry for the many "cons", but as I said under "pros" the method is easy to use.

Sten

pop4 · 03-20-2011, 04:28 PM

Originally posted by Sten

Sorry for the many "cons", but as I said under "pros" the method is easy to use.

No need to be sorry, I was just offering another option for you (and anyone else reading the thread) to try. Hopefully it can help some people, but if not, I'm not going to lose any sleep over it *shrugs*

I personally use the method because it's easy and accurate, and fast too: I checked the focus on 3 bodies, and a bunch of lenses the other day in under 20mins (having a tripod really helps speed up the process). I don't bother with the recommended camera-subject distance either, 2m is good enough for me, while you can easily tell if you're not aligned with the computer screen on the LV preview, aided by the LV magnification (press the info button).

The important thing is that your camera and lens combination focuses well.

03-19-2011, 07:15 AM	#1
Sten Senior Member Join Date: Feb 2011 Location: Stockholm, Sweden Photos: Gallery \| Albums Posts: 103	K-5 auto focus fine adjustment tools? I am new to Pentax, and I have a K-5 and the Pentax 18-135 lens. I am considering auto focus fine adjustment, not because I have seen any need for it - I am just curious if my lens focuses exactly right. Now there are many tools around on Internet, both free and for a charge. What tools are the best of these two kinds? Sten

03-20-2011, 09:25 AM	#8
Sten Senior Member Join Date: Feb 2011 Location: Stockholm, Sweden Photos: Gallery \| Albums Posts: 103 Original Poster	Originally posted by pop4 I tend to use the techniques on this page instead: AF microadjustment for the 1Ds mark III, 1D Mk3, 5D Mk2, 7D Pop4, Thank you very much! I tried your method, and it indicated that my camera/lens combination focuses well. Pros of this method: Easy to use, focusing on an image on your computer screen. Cons: - It can be difficult to achieve the ideal camera-to-subject distance of 50 times the focal length of the lens, in my case 50x135 mm = 6.75 meters. I used a couple of meters which was within the limits of the room. - It is hard to ensure that the computer screen is exactly square on and lined up with the camera. - You need to be observant in order to see if the lens focusing ring moves or not, when you press the shutter to auto focus. - The instructions could me more clear. Sorry for the many "cons", but as I said under "pros" the method is easy to use. Sten Last edited by Sten; 03-20-2011 at 09:40 PM. Reason: Correction

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
K-5 AF fine adjustment - does it work for non Pentax lenses?	Christine Tham	Pentax K-5 & K-5 II	30	12-28-2011 01:35 PM
apply all + apply one = ??? (af fine adjustment)	006	Pentax K-5 & K-5 II	9	03-11-2011 08:40 AM
Lens fine adjustment suggestion to Pentax?	ve2vfd	Pentax K-5 & K-5 II	2	12-09-2010 10:00 PM
Advanced Photo Tools - some cool PP software tools	rawr	Digital Processing, Software, and Printing	3	07-23-2010 11:31 PM
K20D Focus Adjustment	Mallee Boy	Pentax DSLR Discussion	3	07-21-2009 02:57 PM

03-19-2011, 10:16 AM - 1 Like	#2
Acheron Senior Member Join Date: Jul 2009 Location: Croatia Photos: Gallery Posts: 100	Here is a link to pdf which is very useful http://focustestchart.com/focus10.pdf

03-19-2011, 11:59 PM	#3
Sten Senior Member Join Date: Feb 2011 Location: Stockholm, Sweden Photos: Gallery \| Albums Posts: 103 Original Poster	Acheron, Thank you very much! The document is quite interesting, and I will try this method. Sten

03-20-2011, 12:45 AM	#4
pop4 Veteran Member Join Date: Aug 2007 Location: YMML Photos: Gallery Posts: 1,879	I tend to use the techniques on this page instead: AF microadjustment for the 1Ds mark III, 1D Mk3, 5D Mk2, 7D

03-20-2011, 04:11 AM	#5
StigVidar Site Supporter Join Date: Nov 2006 Location: Norway Photos: Gallery \| Albums Posts: 705	You could also take a photo at 135mm f/5,6 of a curbstone at the other side of a road. It is then easy to see if there is front or back focusing.

03-20-2011, 09:03 AM	#6
Sten Senior Member Join Date: Feb 2011 Location: Stockholm, Sweden Photos: Gallery \| Albums Posts: 103 Original Poster	Originally posted by StigVidar You could also take a photo at 135mm f/5,6 of a curbstone at the other side of a road. It is then easy to see if there is front or back focusing. Thank you, StigVidar! I tried your method first, because only minutes after I read about it, my wife took me out for a walk. I then took pictures of a parking lot covered with small concrete squares, after placing two pencils of different colours at the same distance to focus on. The edges of the concrete squares provided a scale which should be most at focus where the pencils were. As you suggested, I used 135 mm/5.6, and had my camera at various distances from the pencils. Looking at the pictures at home in my computer, I got a rough indication that my lens/camera combination focuses well. Pros of this method: very easy and quick to use. Cons: If you want a more exact measurement, then you should use a more sophisticated method as a complement. Sten

03-20-2011, 09:12 AM	#7
Sten Senior Member Join Date: Feb 2011 Location: Stockholm, Sweden Photos: Gallery \| Albums Posts: 103 Original Poster	Originally posted by Acheron Here is a link to pdf which is very useful http://focustestchart.com/focus10.pdf Acheron, Thank you so much! I used your method, and I found it to be the best for me. Furthermore, it showed that my camera/lens combination focuses spot-on without any adjustment, actually better than the example in the instructions of your method. So I am quite happy. Pros of this method: The method is reliable and gives significant results, which you can check afterwards in your computer. The instructions are clear and complete. Cons: There is some easy scissor cutting and glueing, and you should use the right amount of glue (too much makes the paper bulge a little). Sten Last edited by Sten; 03-20-2011 at 10:45 AM.

03-20-2011, 04:28 PM	#9
pop4 Veteran Member Join Date: Aug 2007 Location: YMML Photos: Gallery Posts: 1,879	Originally posted by Sten Sorry for the many "cons", but as I said under "pros" the method is easy to use. No need to be sorry, I was just offering another option for you (and anyone else reading the thread) to try. Hopefully it can help some people, but if not, I'm not going to lose any sleep over it shrugs I personally use the method because it's easy and accurate, and fast too: I checked the focus on 3 bodies, and a bunch of lenses the other day in under 20mins (having a tripod really helps speed up the process). I don't bother with the recommended camera-subject distance either, 2m is good enough for me, while you can easily tell if you're not aligned with the computer screen on the LV preview, aided by the LV magnification (press the info button). The important thing is that your camera and lens combination focuses well.