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02-03-2009, 11:39 PM   #1
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Lensalign Calibration and K20D

Hi,This is my first "real" post in on this forum other than my intro and thought I would make an attempt at a post and contribute to the forum.
Sometimes I tend to ramble a bit so please be kind....

As I have a K20D and it features adjust-ability for 20 lenses and 1 adjustment for the body I thought this could be a nice tool test my camera and help me with my mixed bag of lenses and offer repeatability if a retest is necessary.Like some others I have tried several charts taht are available on the web and personaly found them lacking.....

So I had been observing the progress and reviews on this product offered by Michael Tapes(inventer of WhiBal WB card and this product) at RawWorkFlow.com(I am no way affiliated with him or his company,I am just a customer) and after receiving and testing and adjusting my camera I had some observations to share as other K20D owners maybe interested.
For those not familiar with this product I have provided a link and reviews can be found here also...

Digital Photography - RawWorkflow.com - LensAlign?

As I stated above I want to offer my observations and thoughts so far in my usage of this product on my K20 and not a review as there are plenty by respected sites.
I purchased the "Lite"model and this device uses a mirror to to align the LA tool squarely to the image sensor ,you get the idea I hope...

I had been thinking how I wanted to approach calibrating my lenses and thought it thru and realized I have few manual focus lenses so a calibration on my macro lens would be important that the in camera focus confirmation would be the first step in my mind.After viewing and reading as much on this subject I found I was unable to find any info on calibrating manual focus lenses especially using this product,so what to do?Wanting to know if this would be the proper course to follow(as it made sense to me)I called Michael at RawWokrflow(did not think I would actually speak with him)to ask him the question concerning MF lenses.What followed was an interesting and some what lengthy conversation on the subject and overall usage of his product.
After a friendly greeting he agreed to take a few of my questions...
My first question was concerning Manual Focus lenses and his reply was "Lensalign can be used for Manual lenses also not just AF"
When I asked him"Should I start with calibration by calibrating my body first in respect to the focus confirmation light and adjusting the focus accordingly?"
I went on to ask"My logic would say that the body would need to be first as any adjustment later using the body would affect all other lenses,right?"
He said"Yes,that is the starting point,to adjust the body the focus confirmation light"
After small talk on some of the finer points pertaining to this issue I pointed out that what I have read at his site and the others that have reviewed his product there was no mention of this step(it seemed logical to me) and he assured me he would mention it in his site(we will see).
I also went on to explain a little further to mention I would be using his product on the K20D and mentioned I thought this first step would be important for the "Trap Focus"feature used in this camera.He said that he had used the K20D and he was unaware of this feature and thought it was something that should be on the other "pro"cameras and that by calibrating the body first would also aid in having better focus using the "Trap"feature..
I don't want to bore you with the rest of the conversation but I do want to say I found him to be very nice to speak with,explained without cutting me short and seemed genuinely concerned to my questions and issue.

Now for my calibration my K20d.Let me say I found every one of my lenses out focus and needed adjustment and the body too,at least that is what I found using this product.
Body first,I use my Vivitar Series1 105mm f2.5 a lot as I find it to be razor sharp when focused properly.I have noticed that the confirmation light could not be trusted for focus and like many always had to strain my eyes and hope I got focus,not anymore as once adjusted focus every time on the chart with the light but will do some test with real "macro"shots to see,looks good tho,here is a pic...(EXIF intact)



This lens on my K20D was severely front focused with the focus light and took every bit of adjustment(-10) to to get it to the point shown(Pentax,we should do better IMO)and after a series of test shots I am a lot happier.
So I went on to my Pentax FA50mm f1.4 AF lens, it was back focusing at this point and adjusted with a +3.
Next came Sigma 28 f1.8 ,back focused also,+5 took care of this one.
Tamron 18-250 was a trouble maker as thru the zoom-able focal range it was all over the place,made a little adjust and seemed OK but don't like how it did,maybe my technique but my cheap Quantaray 70-300 LDO macro(re-badged Tamron?)did well and has always given sharp pics and only need small adjust.
Kit lens 18-55 ll,front focus.-4 and checked my other MF lens,acceptable focus with light.

Overall conclusion,I am glad I got this tool and performed this test and adjusted.I was surprised that I found all need some.The body being so far out surprised me and my first impulse was disbelief and wanted to box it up and send it in to Pentax for service and may still if I am not happy but I am willing to do more "real world"shots first to see if my adjustments were worthwhile first.
All lenses seemed more snappy finding focus and did not seem to hunt as much for focus and seemed faster overall,I have no proof to offer but they seem to focus faster but could be wish full thinking.

Here is a photo I took of the Lensalign Lite product I purchased(I know it is not needed but I need some posting practice)



Hope some here may find this helpful or thought provoking.I would be interested in on any thoughts or suggestions related to my method of adjustment using this product and the K20D.
I guess it could be used also for a K10D body adjustment with the hacked? firmware I have read about.I have a K10D too and may just check it in the future but I don't know if I really want to know if and how bad it might be out!

Thankyou for your patience for my long post and look foward to your replies...if any.

Larry."the Pool Guy"

02-04-2009, 01:19 AM   #2
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My experience is that proper adjustment only works, if you are using a target parallel to the sensor. This is the case AFAICS with this tool.
The measure on the right is good to indicate the direction of the error.
It is important to NOT optimize on the Zero mark on the measure, but on optimum sharpness of the target!

I hope that you did not test this at the minimum focussing distance but at a somewhat larger distance of 2-3m?

The suggestion to also fine tume your mirror/view finder system for manual lenses is a good one. I will try this out.

Thanks for the post!
02-04-2009, 04:56 AM   #3
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QuoteOriginally posted by blende8 Quote
My experience is that proper adjustment only works, if you are using a target parallel to the sensor. This is the case AFAICS with this tool.
The measure on the right is good to indicate the direction of the error.
It is important to NOT optimize on the Zero mark on the measure, but on optimum sharpness of the target!

I hope that you did not test this at the minimum focussing distance but at a somewhat larger distance of 2-3m?

The suggestion to also fine tume your mirror/view finder system for manual lenses is a good one. I will try this out.

Thanks for the post!
Yes,I did not use minimum focus distance and I should have been a bit clearer on this point.Actually checking at several distances would be prudent in my opinion although the faster glass was initially set just outside the minimum.The later tests appeared to say this was adequate but of course this is my time doing this and would like some more time to evaluate the settings I chose in using this device.
I was more interested in what others thought of doing the body first and the focus confirmation light check and adjustment.BTW I would think any lens set to MF could check this focus point with a down and dirty on any simple target.
I have noticed peoples comments here and else where(yes that's right,I am admitting to being a super-lurker) that some people have more problems with their lenses than others and if you do a MF test for focus light could indicate the root of the problem.Up to my test I have been pleased with the photos I have taken but had noticed my macro(which is also a good long portrait lens) failed to get focus light lock for sharp photos,it was always off and may throw up a flag to others.With some time I am sure more info and experiences would be coming in on maybe some better techniques will be available but since this is new product and being I was using a Pentax I would share here.

And I would like to say thank you Blende8 for responding to my post and I hope you found it informative.Please have a great day!
02-04-2009, 09:25 PM   #4
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''Let me say I found every one of my lenses out of focus and needed adjustment and the body too,at least that is what I found using this product.''

Motorman,
First, thanks for taking the time to post this thread. I recently upgraded from a K10 to a K20 and unfortunatly discovered that most of my very sharp lens's on the K10 were no longer quite as sharp on the k20. I performed the same tests you outlined above on a homemade set-up and found that while I could bring most lens's back into correct focus (albeit at a maximum -10 setting) there were three that would not come in even at max adj. This brings me to the quote posted at the beginning of my post. I am aware of the +/_ 10 adjustment for the lens's, but do not understand your reference to the ''body'' adjustment? Could you please explaine and tell me where you discovered a reference to this. I read and re-read the manual and can only find instructions for the +/- 10 adj.
Also, has anyone else with a K20 discovered that the range of adjustment was not enough. And if so did you have to return the camera to Pentax?

Thanks
Tony

02-04-2009, 10:58 PM   #5
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"... has anyone else with a K20 discovered that the range of adjustment was not enough. And if so did you have to return the camera to Pentax?"

Here's my experience with the K20D thus far:

Yes, I found with my FA 50 f1.4 on my K20D that it was front-focusing and the adjustment range was nowhere near enough.

No, I have not yet returned the camera or lens to Pentax and I'm not sure if I want the hassle (plus parting with my equipment for a while). I've simply relied on manual focus to get things sharp because I don't trust the autofocus.

I should also add that autofocus with my 12-24 (which I bought after performing focus tests on the FA 50) is inconsistent. When focusing at the hyperfocal distance in a landscape scene (which is infinity on the lens barrel), I have to turn the focus ring a little bit back to ensure focus from foreground to background; otherwise, only the foreground or background is tack sharp or the whole image is out of focus.

I'm glad that others report this problem, but only in the sense that I'm not imagining things. Now I have to decide whether it would be worth it to send my K20D in for adjustments.
02-05-2009, 02:08 AM   #6
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QuoteOriginally posted by AV82GOLF Quote
This brings me to the quote posted at the beginning of my post. I am aware of the +/_ 10 adjustment for the lens's, but do not understand your reference to the ''body'' adjustment? Could you please explaine and tell me where you discovered a reference to this. I read and re-read the manual and can only find instructions for the +/- 10 adj.
Also, has anyone else with a K20 discovered that the range of adjustment was not enough. And if so did you have to return the camera to Pentax?
Regarding point 1:
What he probably means is this: The light path to the AF system might be slightly different compared to the direct path to the sensor. This would mean that a sharpness indication (green light in the viewfinder) not necessarily means a sharp image on the sensor. To correct that you can set a correction value (via Apply to all). This then helps to focus manual lenses correctly (via the green light).

I would say though that this should only be a temporary solution. In such a case I would send in the camera for calibration.


Regarding point 2:
I have heard that especially the Limited FA lenses needed more than what is available.
My FA50 needs -6, at the minimum focus distance even -10.
02-05-2009, 03:24 AM   #7
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QuoteOriginally posted by blende8 Quote
My experience is that proper adjustment only works, if you are using a target parallel to the sensor.
Makes sense and the service manual for the GX-10 shows such a parallel target but I wonder why. If the target is a simple black to white transition, how can it make a difference at what angle you look at this transition? This would mean that the AF system sees a difference between a parallel and a tilted surface even if it has just one colour. But it cannot focus on either and needs a transition. The latter has no tilt, though, even when the plane it is on is tilted.

QuoteOriginally posted by blende8 Quote
It is important to NOT optimize on the Zero mark on the measure, but on optimum sharpness of the target!
How do you optimise sharpness of the target? By a series of shots with focus bracketing and evaluating sharpness of the target? Of what use is the ruler then, if one should not optimise on the zero mark?
The proportion between the in-focus areas in front and at the back of the target depends on the distance between camera and target but for normal measuring distances, say 2m, it is very close to 50:50.
02-05-2009, 04:20 AM   #8
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Well, I have no real answers.
My guess with those skewed targets is that the AF sensor base is quite large and if not all points on the target are at the same distance it is impossible to say to which point the AF system actually focussed.

QuoteQuote:
How do you optimise sharpness of the target? By a series of shots with focus bracketing and evaluating sharpness of the target?
Yes.

QuoteQuote:
Of what use is the ruler then, if one should not optimise on the zero mark?
It shows you in what direction you should make the change.
Ideally, of course, both results should coincide, but from my experience optimizing on the ruler is not very exact.

02-05-2009, 04:42 AM   #9
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Why does not just pentax do this with at least all the DA lenses and save it into a firmware, so everyone could download it?
And if you have any FA or older lenses you could save them insteed of any other.


I found this thread very intressting, but I don't see why we costumers have to do this and not pentax themselves

I have just buy a k20d and a DA 16-45 lens. How do I do or know what to do, for make this focus correctly?

Have I understand that this is just about autofokus on lenses?? or does it acctually correct where the real sharpness-level should be?
02-05-2009, 06:03 AM   #10
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QuoteOriginally posted by AV82GOLF Quote
''Let me say I found every one of my lenses out of focus and needed adjustment and the body too,at least that is what I found using this product.''

Motorman,
First, thanks for taking the time to post this thread. I recently upgraded from a K10 to a K20 and unfortunately discovered that most of my very sharp lenses on the K10 were no longer quite as sharp on the k20. I performed the same tests you outlined above on a homemade set-up and found that while I could bring most lens's back into correct focus (albeit at a maximum -10 setting) there were three that would not come in even at max adj. This brings me to the quote posted at the beginning of my post. I am aware of the +/_ 10 adjustment for the lens's, but do not understand your reference to the ''body'' adjustment? Could you please explain and tell me where you discovered a reference to this. I read and re-read the manual and can only find instructions for the +/- 10 adj.
Also, has anyone else with a K20 discovered that the range of adjustment was not enough. And if so did you have to return the camera to Pentax?

Thanks
Tony
First I want to say thank you Tony for responding to my post,I was becoming worried that no one had found this interesting enough after over a 100 views to even comment,well 1,thanks Blende8 also!

Now to answer your question the best I can.In my Pentax manual for the K20 page 106 are the instructions for the adjustments and there are 2 options,"apply all"(the body) and "apply one"(for the lenses,up to 20) and it is my understanding and experience that they work together.Example:if you find all or most of you AF glass front focuses the "all"would bring them all down to a better starting point to work with but I chose a different approach and thought as the instructions IMO were not clear to me.I had noticed when using my MF macro lens the focus light seen in the view finder did not indicate sharp focus and could not be trusted but dismissed this as a quirk for MF and only once I received the Lensalign tool logically thought it out as I mentioned above in my earlier post.I thought it important to confirm the focus light with sharp focus first with MF and Michael Tapes(the inventor)confirmed this to be the proper approach for the K20D as Pentax allows this where C+N+S do not,thanks Pentax!So I thought of this as a "body" adjustment and "apply all" in the menu(in custom setting,#35 to do this)for my starting point before I went on to do the AF on my lenses,does this make sense?for me it does as it is part of the focus system of the camera.Everything I had read to date fails to mention this point and I thought it was important to mention it here and I feel it should not be over looked as this adjustment later would be applied to "all" if adjusted and would affect all lenses adjusted.Using the feature this way would allow an adjustment of up to +/- 20,...(+/-10 for"all" and +/-10 per lens).

So to answer your question there is a+/-20 total using both features in the menu and the do work together,if you do see all your lenses FF by an specific amount then do "all" to bring them into a closer overall range and then then lens by lens make your individual adjustments with "one".

As for the Lensalign tool,I do think this is the best tool yet(and I had tried others) to perform this test for the consumer as it offers a target that gets squared up to the sensor first before the DOF focus point is determined and is repeatable.Your fastest glass will benefit the most as it will have the narrowest DOF which is most important when used wide open to have the proper focus.
02-05-2009, 06:21 AM   #11
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QuoteOriginally posted by enoxatnep Quote
"... has anyone else with a K20 discovered that the range of adjustment was not enough. And if so did you have to return the camera to Pentax?"

Here's my experience with the K20D thus far:

Yes, I found with my FA 50 f1.4 on my K20D that it was front-focusing and the adjustment range was nowhere near enough.

No, I have not yet returned the camera or lens to Pentax and I'm not sure if I want the hassle (plus parting with my equipment for a while). I've simply relied on manual focus to get things sharp because I don't trust the autofocus.

I should also add that autofocus with my 12-24 (which I bought after performing focus tests on the FA 50) is inconsistent. When focusing at the hyperfocal distance in a landscape scene (which is infinity on the lens barrel), I have to turn the focus ring a little bit back to ensure focus from foreground to background; otherwise, only the foreground or background is tack sharp or the whole image is out of focus.

I'm glad that others report this problem, but only in the sense that I'm not imagining things. Now I have to decide whether it would be worth it to send my K20D in for adjustments.
I have the FA50 and found it front focused also,I don't have the 12-24 so I can't comment except my AF zooms have given me problems also in checking them but would suggest rereading my posts and checking the focus light confirmation(for me the most important first step to start with) with MF with the FA50 first using the "all"(body)adjustment then go to AF and set that lens with"one"feature in the menu and move on to the other lenses.

And let me add that I am no expert here,I just reeived this tool and this is the first time doing this and wanted to share what I had found as to my knowledge no one else has done this here(with this tool) and I may be the first to use this tool on this forum with Pentax K20D.
02-05-2009, 06:31 AM   #12
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QuoteOriginally posted by blende8 Quote
Well, I have no real answers.
My guess with those skewed targets is that the AF sensor base is quite large and if not all points on the target are at the same distance it is impossible to say to which point the AF system actually focussed.


Yes.


It shows you in what direction you should make the change.
Ideally, of course, both results should coincide, but from my experience optimizing on the ruler is not very exact.
Yes having a sharp target image is the goal and the ruler helps determine where the DOF is in relationship to the focused target IMO.

Thanks Blende8 for helping this thread along,it is apparent to me you have a good knowledge on this topic and brought good points up!

It is my goal to better understand this relationship and better use this tool.
02-05-2009, 07:58 AM   #13
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QuoteOriginally posted by Motorman Quote
In my Pentax manual for the K20 page 106 are the instructions for the adjustments and there are 2 options,"apply all"(the body) and "apply one"(for the lenses,up to 20) and it is my understanding and experience that they work together.
I'm sorry, but this is not correct.
The manual says:
"If an adjustment value has been saved using Apply One and you press
the OK button with [Apply All] selected in Step 6, the Apply All value is
used instead of the Apply One value."


You can only use one or the other. Apply All overrides.
02-05-2009, 08:33 AM   #14
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QuoteOriginally posted by blende8 Quote
I'm sorry, but this is not correct.
The manual says:
"If an adjustment value has been saved using Apply One and you press
the OK button with [Apply All] selected in Step 6, the Apply All value is
used instead of the Apply One value."


You can only use one or the other. Apply All overrides.
Well I am learning and don't want to indicate that my interpretation is set in stone.
I will reread and retest and what you say in fact may be true.This is a new area for me and others and will share more of my experience later.

I will be making more tests when time alows....

Thanks for your input and lets keep it up till the proper answer is more apparent at least for me...
02-05-2009, 01:19 PM   #15
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Hi Larry (and welcome to the fold from a native Atlantan)!

I've been wondering about this Lens Align tool, so your experiences are interesting. Thanks for posting this.

Was there any drawback you could see about using the "lite" version versus the "full" version? The only difference I could see is that my wallet would be "lighter" if I bought the "full" version.
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