Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
12-23-2013, 07:55 AM   #1
Site Supporter
disco_owner's Avatar

Join Date: Apr 2012
Location: Sydney
Photos: Gallery | Albums
Posts: 1,611
AF Microfine adjustment Using a LensAlignt or equivalent

What am I doing wrong ?


1. I placed the LensAlign on Tripod and Levelled it.
2. with K-5 II s on Tripod and Level I Sighted the target with the lens and checked and Fine Adjusted the lens and target until the sensor plane was exactly in line and parallel to the Focal Plane of target.
3. took a Series of shots from target and looked closely and not really sure how to interpret the results ??


Can someone please help by posting a Link to a Detailed Video or Literature on " How to " of Micro fine adjustment using the LensAlign?




12-23-2013, 08:01 AM   #2
Pentaxian
Kozlok's Avatar

Join Date: Jun 2012
Location: Albuquerque
Photos: Gallery
Posts: 1,793
I think maybe you need to use a larger aperture (smaller f number). Your DOF is too deep to draw a conclusion.
12-23-2013, 08:54 AM   #3
Site Supporter
jatrax's Avatar

Join Date: May 2010
Location: Oregon
Photos: Gallery | Albums
Posts: 10,772
What lens are you using? As noted above you need to use a large aperture (small f number) Use the smallest f number your lens has. Also the distance to target matters, I have read anything from 10x to 50x the focal length of the lens. Not sure which is right. Note that with very wide angle lenses it will be hard to get a small enough depth of focus to really test, and slow lenses like the kit lens will also have a large depth of focus making it hard to test.

And may I suggest you read the manual? AF fine tuning is not required, and honestly it is just as easy to make things worse as it is to make things better. Often the margin of error in the testing is larger than the original error. Unless you have things set up precisely and run multiple tests you have a good chance of making the lens more out rather than less.

Here is article on AF tuning that might help: Fixing Front and Back Focus - Introduction - PentaxForums.com
And here is the lens align site: LensAlign
12-23-2013, 10:08 AM   #4
Loyal Site Supporter




Join Date: May 2011
Location: Richmond, Virginia USA
Photos: Gallery | Albums
Posts: 2,649
RockvilleBob knows this inside and out...i think he was a beta tester

12-23-2013, 11:12 AM   #5
Loyal Site Supporter
RockvilleBob's Avatar

Join Date: Dec 2011
Location: Lewes DE USA
Photos: Albums
Posts: 1,699
I have had very good success with LensALighn and recently with the FocusTune3 product. LensAlighn is a visual tool you use to compare AF adjustment settings.

Some of the key points hve been pointed out - largest aperture for smallest DOF is important. Also there is a minimum distance for each lens as specified in the Distance Tool LensAlign

You also need to double check the documentation and videos available https://mtd.tenderapp.com/kb/lensalign-how-to/documentation-videos-distance-tool

So Parallel alignment, proper distance for the focal length and smallest largest aperture.
12-23-2013, 11:22 AM   #6
Pentaxian
traderdrew's Avatar

Join Date: Jun 2010
Location: Florida
Photos: Gallery | Albums
Posts: 570
I think that is your sample image and it looks like your three holes are not perfectly aligned. Lens Align recommends for every 100 millimeters of focal length, you should be 8.1 feet away from your target. In other words, if your lens is a 200mm, test it at a little more than 16 feet away.
12-23-2013, 11:44 AM   #7
Loyal Site Supporter
RockvilleBob's Avatar

Join Date: Dec 2011
Location: Lewes DE USA
Photos: Albums
Posts: 1,699
I concur about the alignment. You should be looking through the holes to the rear red targets which also have holes. When you take a picture the holes shouls look like an archery target with a red bulls-eye with a hole in the center. You should line up on target B, I think C is for macro lenses. It appears as if there may be an extra piece of white paper behind the targets that do not permit sighting of the rear red bulls-eye. Some keys include: Proper alignment of the lens with the target, proper distance depending on focal length and wide open aperture.
12-23-2013, 03:04 PM   #8
Site Supporter
disco_owner's Avatar

Join Date: Apr 2012
Location: Sydney
Photos: Gallery | Albums
Posts: 1,611
Original Poster
QuoteOriginally posted by Kozlok Quote
I think maybe you need to use a larger aperture (smaller f number). Your DOF is too deep to draw a conclusion.
Hi Kozlok , The F-Stop setting I used last Night was F8 , I was using a Da18-135 and Da*55 lens for this AF test. I can see what you mean by shooting the target with a Wideoen aperture , it will give a really good visual indication of the numbers placings on the ruler.

QuoteOriginally posted by jatrax Quote
What lens are you using? As noted above you need to use a large aperture (small f number) Use the smallest f number your lens has. Also the distance to target matters, I have read anything from 10x to 50x the focal length of the lens. Not sure which is right. Note that with very wide angle lenses it will be hard to get a small enough depth of focus to really test, and slow lenses like the kit lens will also have a large depth of focus making it hard to test.

And may I suggest you read the manual? AF fine tuning is not required, and honestly it is just as easy to make things worse as it is to make things better. Often the margin of error in the testing is larger than the original error. Unless you have things set up precisely and run multiple tests you have a good chance of making the lens more out rather than less.

Here is article on AF tuning that might help: Fixing Front and Back Focus - Introduction - PentaxForums.com
And here is the lens align site: LensAlign

I couldn't agree more, that above is merely just a test to check the AF Front/back Focus of my 2 Most used lenses , Da*55 and Da18-135. What has triggered this test was that I recently noticed a Lot of My shots where Soft ( Note Not completely in focus ) when taking Portrature shots of 2 or 3 subjects standing inline either at parties or weddings.


the link was great Help.

QuoteOriginally posted by RockvilleBob Quote
I have had very good success with LensALighn and recently with the FocusTune3 product. LensAlighn is a visual tool you use to compare AF adjustment settings.

Some of the key points hve been pointed out - largest aperture for smallest DOF is important. Also there is a minimum distance for each lens as specified in the Distance Tool LensAlign

You also need to double check the documentation and videos available https://mtd.tenderapp.com/kb/lensalign-how-to/documentation-videos-distance-tool

So Parallel alignment, proper distance for the focal length and smallest largest aperture.

Thanks Bob , I will read the Literature and watch the videos.
QuoteOriginally posted by traderdrew Quote
I think that is your sample image and it looks like your three holes are not perfectly aligned. Lens Align recommends for every 100 millimeters of focal length, you should be 8.1 feet away from your target. In other words, if your lens is a 200mm, test it at a little more than 16 feet away.




The distance to target set at 25 x Times the FL , as I was shooting at 50mm FL I measured the Distance using a Tape measure to get it close to the recommended distance.1.25 m.

QuoteOriginally posted by RockvilleBob Quote
I concur about the alignment. You should be looking through the holes to the rear red targets which also have holes. When you take a picture the holes shouls look like an archery target with a red bulls-eye with a hole in the center. You should line up on target B, I think C is for macro lenses. It appears as if there may be an extra piece of white paper behind the targets that do not permit sighting of the rear red bulls-eye. Some keys include: Proper alignment of the lens with the target, proper distance depending on focal length and wide open aperture.

I placed the White paper after I sighted the target with the lens , I did exactly what you have described and looked through Target B back towards the lens.


I'll set this test up again today and have another play with the LensAlign

12-23-2013, 07:07 PM   #9
Site Supporter
disco_owner's Avatar

Join Date: Apr 2012
Location: Sydney
Photos: Gallery | Albums
Posts: 1,611
Original Poster
ok ,Does it look like the Da* 55 needed a +3 AF Microfine adjustment using the LensAlign Calibration system to get the Zero sharpest ?


All shots were taken wideopen with both Camera and Lens align on tripod and level.



No. 1 ( No Adjustment )



No 2. ( + 1 Adjustment )



No 3. ( + 2 Adjustment )



No 4. ( + 3 Adjustment )





No 5. ( + 4 Adjustment )



No 6. ( + 5 Adjustments )




I spent a Considerable amount of time setting up the Lens Align and taking test shots to ensure I had the Bulls eye dead centre and that the Plane of Focus was parallel to the sensor plane there was no Error Introduced.
12-24-2013, 05:01 AM - 1 Like   #10
Loyal Site Supporter
RockvilleBob's Avatar

Join Date: Dec 2011
Location: Lewes DE USA
Photos: Albums
Posts: 1,699
it looks like you got good results this outing.
Just a suggestion: you might want to look at using FocusTune3 see
It works in conjunction with LensAlighn and automates the process. You will find, taking say 5 shots at each AF Fine Adjustment setting, that the results ary for a given setting. FocusTune 3 provides the graphic information you need to make an optimal setting.
Personally I used LensAlighn for several years and always had trouble make a selection between settings. Adding more shots at each setting only made matters worse. FocusTune 3 solved this for me giving repeatable results. I used it for all my autofocus lenses. It was important to have a strong light on the target and a dark background helps.
Contrary to what I thought prior to FocusTune 3 was that there is a fair amount of variance at each setting but there is a trend line that helps pick the best setting.
Here are some links to previous threads
https://www.pentaxforums.com/forums/172-pentax-k-3/242652-k-3-focustune-update.html
https://www.pentaxforums.com/forums/10-pentax-slr-lens-discussion/244174-af-f...om-lenses.html
For zoom lenses I used the biggest aperture and longest focal length.
Overall I have been very pleased with the results see:
https://www.pentaxforums.com/forums/122-lens-clubs/55946-300mm-plus-lens-club...ml#post2620373
500mm lens required 42 feet - I used a large meeting room
12-25-2013, 07:42 AM   #11
Site Supporter
disco_owner's Avatar

Join Date: Apr 2012
Location: Sydney
Photos: Gallery | Albums
Posts: 1,611
Original Poster
Thank you very much to take the time to write the detail post RockvilleBob. I watched the video and the graphical representation provides a very useful tool to take away any guess work . Is this software package also available from the LensAlign website ? I guess the software and the LensAlign complement eachother nicely.
12-25-2013, 09:02 AM   #12
Pentaxian
aurele's Avatar

Join Date: Jan 2011
Location: Paris, France
Photos: Albums
Posts: 2,967
keep in mind that Lens like the DA*55 can have some focus shift depending on the aperture.

So i suggest you to adjust your Lens for your most used aperture with it.
12-25-2013, 09:23 AM   #13
Site Supporter
disco_owner's Avatar

Join Date: Apr 2012
Location: Sydney
Photos: Gallery | Albums
Posts: 1,611
Original Poster
QuoteOriginally posted by aurele Quote
keep in mind that Lens like the DA*55 can have some focus shift depending on the aperture.

So i suggest you to adjust your Lens for your most used aperture with it.
The test for lens alignment is done with the lens set at widest aperture of that lens if it's a prime , if its a zoom ,the LensAlign test should be done at longest FL with aperture set to widest. After making +3 AF microfine adjustment da55 yields better results at wider apertures as this is where I shoot 90% of the time anywhere between F1.8 to about F4.0.
12-25-2013, 12:25 PM   #14
Loyal Site Supporter
RockvilleBob's Avatar

Join Date: Dec 2011
Location: Lewes DE USA
Photos: Albums
Posts: 1,699
QuoteOriginally posted by disco_owner Quote
Thank you very much to take the time to write the detail post RockvilleBob. I watched the video and the graphical representation provides a very useful tool to take away any guess work . Is this software package also available from the LensAlign website ? I guess the software and the LensAlign complement eachother nicely.
Yes - available at the same web site as LensAlighn
01-29-2014, 02:00 PM   #15
Loyal Site Supporter
comprock's Avatar

Join Date: Jan 2014
Location: Portland, Montreal, Menton, Dubai, Pondicherry, Singapore, Kaohsiung, Coupeville
Photos: Gallery
Posts: 529
I'm running +2 with my DA* 55 on K-5 II. Seems to help.
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
adjustment, af microfine adjustment, lens, lensalign, pentax help, plane, target, tripod
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Wanted - Acquired: Pentax-a 28mm 2.8 or equivalent jrcastillo Sold Items 2 08-24-2013 01:37 PM
K-01 , no AF fine adjustment , is this a problem ? kamisu Pentax DSLR Discussion 17 03-24-2012 10:52 AM
AF adjustment with 1.7 AF TC djc737 Pentax K-5 3 02-04-2012 12:12 PM
Max AF adjustment +-10 or +-20? bengibollen Troubleshooting and Beginner Help 3 07-21-2011 03:23 PM
Anyone using the af adjustment oh there 645d kuau Pentax Medium Format 3 03-06-2011 10:59 AM



All times are GMT -7. The time now is 03:04 AM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top