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  #1  
Old December 10th, 2008, 12:48 PM
Asher Kelman Asher Kelman is offline
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Default LensAlign™ Seen! Announcement coming soon!

RawWorkflow.com's Michael Tapes has been working in secret for some time to produce a device for dealing with the back focus or front focus we discover in our lenses. Bart Van Der Wolf, (see his extensive and original contributions here), and others have sought to provide solutions and they moved us forward considerably.



Photo (crop): Nicolas Claris "Bart Van Der Wolf's focus target"

The number of posts and amazing popularity of that thread is an indication of the widespread interest in the problem of poorly set focus of lenses with respect to the focal plane of the cameras they are designed for.

The prospect release of LensAlign™ is being discussed in DPReview here. Amazing how cynical dpreview folk can be. Some times the folk there show off lenses using pictures of cat's whiskers, LOL!

Manufacturers often have denied the problems with their lenses. Back focus with Canon cameras was most often blamed on the technique of focusing using the center spot on a high point in the scene, for example a model's eyes, and then recomposing. In that case the distance of the oblique line of sight to the upper part of the image is longer than the direct orthogonal line to the center of the field. Thus, the model's eyes were not in focus in the final picture.

We all know that now, but still lenses are inaccurately set coming out of the box, brand new! The first solution has been for the companies to admit there was an issue, which they did and offer the solution of returning the camera and a set of lenses for custom adjustment. So MFRS like Canon and Nikon are now providing that service.

Now however, modern cameras allow for fine adjustment of several lenses and storage of these adjustments in the camera. With live view this has been made relatively easy for one to do on ones own using the technique of Bart and/or a ruler at an angle for the adjustment and to check the result.

However, adjustment can be improved perhaps. That's what Michael sought to achieve. He researched different approaches and consulted with a number of the photographers who were working on this challenge.

The result, LensAlign™ is sitting before me. No it's not an LCD screen with Bart's target. That I can assure you of! It's under NDA so I regret I cannot tell you how it works or it's structure. I can say that it's well thought out, precise and very impressively manufactured. It is set up to work for any camera with or without live view on the LCD screen. However, one can only determine the state of adjustment on older cameras and not alter the focus of the lenses without sending them to the service center. With the newer cameras and LensAlign™ you are going to be able to test and reset your lenses and store the information in the camera so it's all an easy reliable process.

I wish I could show you more, but I cannot!

I'll post more when the ban on disclosure is lifted. For now, it looks good! I think I’m allowed to say that!

Asher
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Last edited by Asher Kelman; December 11th, 2008 at 10:39 PM. Reason: "crop" of Nicoas Claris Photograph emphasized :)
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  #2  
Old December 10th, 2008, 02:05 PM
Daniel Buck Daniel Buck is offline
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I've never really had any problems with focusing, but nice to see some development on it :-)
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  #3  
Old December 10th, 2008, 02:40 PM
Bart_van_der_Wolf Bart_van_der_Wolf is offline
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Quote:
Originally Posted by Daniel Buck View Post
I've never really had any problems with focusing, but nice to see some development on it :-)
Hi Daniel,

Surely, you jest...

Even if you only use manual focus, you can only focus as accurately as the positioning of the groundglass allows, and there is always a tolerance in the shims used. Autofocus has some tolerance around a mean, if only due to mechanical play. So, surely you jest if you say that you never had any problems with focusing...

Cheers,
Bart
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  #4  
Old December 10th, 2008, 02:56 PM
Asher Kelman Asher Kelman is offline
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Quote:
Originally Posted by Daniel Buck View Post
I've never really had any problems with focusing, but nice to see some development on it :-)
Hi Daniel,

With large format work, for sure you don't use it. However, when you use a servo motor on your lenses adapted to a motorized Chamonix 8x10, you'll need one of these, LOL!

It's a real problem for cameras with interchangeable lenses. The designs also may cause focus to shift as one zooms. The truth is that cameras should have these corrections built in and also software for auto adjustment with provided targets. That they don't leaves creative minds to come up with solutions.

Asher
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  #5  
Old December 10th, 2008, 03:42 PM
Daniel Buck Daniel Buck is offline
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Quote:
Originally Posted by Bart_van_der_Wolf View Post
Hi Daniel,

Surely, you jest...

Even if you only use manual focus, you can only focus as accurately as the positioning of the groundglass allows, and there is always a tolerance in the shims used. Autofocus has some tolerance around a mean, if only due to mechanical play. So, surely you jest if you say that you never had any problems with focusing...

Cheers,
Bart
well yes, maybe the word *never* was a little strong, but I don't have any recurring issues with focusing that I can attribute to hardware/software problems. I shoot my 85/1.2 and 135/2.0 wide open pretty often, and majority of the time I hit the focus that I want, even if I'm using auto focus (usually shooting rocks, trees, or cars wide open). I can't say that the auto focus has 'problems' and consistently misses focus. Sometimes the focus does not lock or gets tricked by odd contrast (or low light), but it's usually pretty obvious when that happens, so hitting the focus button once or twice more pretty much always does the trick unless there just isn't enough light. I have only used one zoom lens extensivly (a friend's 70-200/2.8) and didn't notice any focusing issues with that either.

When shooting portraits (something I'm only recently getting into), it's more difficult to tell since both myself and the subject are not locked down, so there are alot of missed focus shots. But when I'm on a tripod shooting a stable object wide open, I rarely have any issues focusing. I have a split focusing screen in my 1Ds2 for help with my manual lenses, but even my autofocus Canon lenses seem to auto focus with out problems. I use center focusing, and have the * button mapped to auto focus.

I even did a self-portrait, 85mm f1.2, and nailed dead focus on my eye :-) (after a few tries though, haha!)
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  #6  
Old December 11th, 2008, 02:15 PM
Asher Kelman Asher Kelman is offline
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Default Focus Micro adjustment is only part of what we should be allowed to do!

Here's my updated comment from a current dpreview.com thread.

The solution to all this and so many other problems with digital cameras lies in solving a more generic complaint I have of digital cameras. We are really being short-changed in so many more ways. Here's what's the fundamental issue and the route to all solutions we'd imagine. With digital cameras, unlike the PC and the Mac or other computing systems sold in millions, the MFRs don't provide access to the SDK.
We cannot readily alter the digital camera's firmware. So, imagine all the creative and capable minds currently locked out! So, for now, we're utterly restricted! How short-sighted!
There's one camera, I believe a G series Canon that didn't have RAW and someone hacked it! All the cameras have potential capabilities not even imagined by the MFRS. This focus problem is just one issue.

Take Canon's focus micro-adjust for example. At the moment there are two kinds of adjustments. The first sets focus for all lenses and the second allows micro adjustment for up to 20 lenses, one per lens. The problem is that a 24-105 mm zoom can only have one micro adjustment at your favorite focal length. Pretty silly if you ask me! I'm betting that Canon's limit of 20 storing calibrations, (on 20 lenses, one per lens), could be altered. We might then assign 4 adjustments to one favorite zoom lens it would switch to different calibrations as one racked though increasing focal lengths.

LensAlign™: In the meanwhile, fine-adjusting one's lenses or getting evidence that your lens is within tolerance is what the LensAlign™ is offered to do well and fast. It can readily be replaced with many other methods, but LensAlign™ appears convincingly authoratative. I'll be working with it over the weekend. maybe, I'll use it to immediately check lenses I buy to make sure I don't have a lemon out of the box! Is such a device critical for this? No! However, it might well be a useful tool to have.

Remember, any way, Canon and other companies have leeway for what they consider calibrated and with their MFRS tolerance. 3 pictures focussed on the same target are not warranted to all be in identical sharp focus, but within a range of focus depth.

If the lens is really out of whack, it should be sent back to the service center as it could have a host of other issue too. So, at the very least, we should look out for centering, symmetry of illumination and sharpness and not just central point focus.

Asher
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  #7  
Old December 11th, 2008, 03:45 PM
Bill Miller Bill Miller is offline
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Quote:
Originally Posted by Asher Kelman View Post
..................sold in millions, the MFRs don't provide access to the SDK.
Asher

Asher, I have the SDK for Canon's camera's and regular updates are available, the current one is Nov.12, 2008

http://fotosnow.com/Canon_SDK_Compatibility_Charts.htm

For Nikon

For Olympus

As for adjusting lenses even though the latest cameras allow micro adjustment, that is not the whole answer. Canon Tech support states "this is a feature, and the lens/camera should be sent to Canon Repair to insure they meet original specifications."
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  #8  
Old December 11th, 2008, 04:02 PM
Asher Kelman Asher Kelman is offline
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Quote:
Originally Posted by Bill Miller View Post
Asher, I have the SDK for Canon's camera's and regular updates are available, the current one is Nov.12, 2008

As for adjusting lenses even though the latest cameras allow micro adjustment, that is not the whole answer. Canon Tech support states "this is a feature, and the lens/camera should be sent to Canon Repair to insure they meet original specifications."
Hi Bill

As I already emphasized,

Quote:
Originally Posted by Asher Kelman
If the lens is really out of whack, it should be sent back to the service center as it could have a host of other issue too.
As far as the SDKs are concerned, I'd be interested to know from software engineers whether or not what's supplied is sufficient to have open access to all the features we'd love to control. Somehow, I doubt it or else many other companies would be making plugins or overlays to bring us enhanced functionality and reassignments of controls to our own tastes.

Asher
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  #9  
Old December 11th, 2008, 05:03 PM
Doug Kerr Doug Kerr is offline
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Hi, Asher,

Quote:
Originally Posted by Asher Kelman View Post
RawWorkflow.com's Michael Tapes has been working in secret for some time to produce a device for dealing with the back focus or front focus we discover in our lenses.
. . . .
The result, LensAlign™ is sitting before me.
. . . .
I'll post more when the ban on disclosure is lifted.
Do we know when Michael plans to release his new device?

Best regards,

Doug
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  #10  
Old December 11th, 2008, 05:39 PM
Asher Kelman Asher Kelman is offline
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Quote:
Originally Posted by Doug_Kerr View Post
Do we know when Michael plans to release his new device?
The answer is "Yes!" We do know! I have to parse the letters I receive and determine what prohibitions refer to what components.

LensAlign™ Pro – shipping next week
LensAlign™ Lite – Shipping early Jan

Pricing to be announced tomorrow morning


I can also let you in on a link to two "quick and dirty" videos that will be unlocked to morrow with the password, aptly named:
friday

I haven't seen the fore-mentioned videos, so let that be a full warning. I also don't want any flak about presenting anything of the given tawdry-sounding description.

So with that caveat, and in the expectation of the full well conceived form to follow, here's the link for 12:00 noon, the unlock time, (in Florida, I guess)!

Your obedient servant,

Asher

I discovered that lower case "friday" is unlocked right now!
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Last edited by Asher Kelman; December 12th, 2008 at 12:34 AM.
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  #11  
Old December 11th, 2008, 10:21 PM
Bill Miller Bill Miller is offline
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Quote:
Originally Posted by Asher Kelman View Post
Hi Bill


As far as the SDKs are concerned, I'd be interested to know from software engineers whether or not what's supplied is sufficient to have open access to all the features we'd love to control. Somehow, I doubt it or else many other companies would be making plugins or overlays to bring us enhanced functionality and reassignments of controls to our own tastes.

Asher
I'm curious what features would you like to control??? What enhancements or reassignments of controls would you like to see?

Let me ask you this do you have more control today with your 35mm they you had 10 years ago? Do you have more control then your 8x10 offers??
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  #12  
Old December 11th, 2008, 10:23 PM
Bill Miller Bill Miller is offline
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Default Camera AF Microadjustment

Here is a link to a UK site, with instructions on micro-adjustment. BTW its free.

http://www.northlight-images.co.uk/a...djustment.html
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  #13  
Old December 11th, 2008, 10:44 PM
Asher Kelman Asher Kelman is offline
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Quote:
Originally Posted by Bill Miller View Post
I'm curious what features would you like to control??? What enhancements or reassignments of controls would you like to see?
re-read post # 6 on zoom lenses. Other functions? I'm sure you could think of a few.
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  #14  
Old December 12th, 2008, 12:06 AM
Cem_Usakligil Cem_Usakligil is offline
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Quote:
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Here is a link to a UK site, with instructions on micro-adjustment. BTW its free.

http://www.northlight-images.co.uk/a...djustment.html
Hi Bill,

Surely you must be aware of the thread here in OPF started by Bart van der Wolf a year ago about micro-adjusting the lenses. With more than 28 thousand views, it is one of the best read threads on OPF ever. From what I can see in the link you've provided, they suggest to use almost the same procedure as Bart's.
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  #15  
Old December 12th, 2008, 12:51 AM
Daniel Buck Daniel Buck is offline
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Quote:
Originally Posted by Bill Miller View Post
Here is a link to a UK site, with instructions on micro-adjustment. BTW its free.

http://www.northlight-images.co.uk/a...djustment.html
his findings seem to mirror my own. My 15/2.8 fish focuses just fine, and so has the 70-200 that I've used several times. My 85/1.2 and 135/2.0 don't miss focus either. :-)
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  #16  
Old December 12th, 2008, 09:15 AM
Doug Kerr Doug Kerr is offline
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I'm always amazed at the course a posting on this forum can lead to.

Asher points out that today (presumably at 20081212 1200 +5) Michael Tapes will announce a new product, evidently a "tool" for use in checking camera/lens focus behavior, probably including in connection with exploiting the AF microadjust feature in modern Canon EOS cameras.

Presumably few of us have seen much "official" information on the device.

But, in anticipation of its unveiling, we have here earnest discussions as follows:

• "What this really reminds us is that Canon has not revealed the inner workings of their cameras so we could do all kinds of really beneficial things."

• • "Well, if Canon would make available an SDK, it would take care of that"

• • • "But they have."

• • • • "But it doesn't."

• "I don't see what the point of such a tool is. Everything I have focuses just fine."

Well, I guess, if we mostly haven't seen the tool, and haven't seen any statement by the manufacturer as to exactly what its intended uses are, we have to talk about something.

I sure hope we don't spend the rest of the morning embroiled in concern that Michael may use in the construction of the tool materials from a country that does not respect the human rights of photographers.

Best regards,

Doug
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  #17  
Old December 12th, 2008, 09:51 AM
Daniel Buck Daniel Buck is offline
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Doug, would you like us to stop posting? I've got no problem doing that :-) All my posts have at least been photography related, I don't introduce politics, religion, or other (what I would call 'sensitive') subjects to my postings. If being a tad bit off topic bothers you, then these announcements should be mad as locked posts, so that no discussion can happen ;-) What would you have us discuss... the release date?
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  #18  
Old December 12th, 2008, 12:02 PM
Doug Kerr Doug Kerr is offline
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The LensAlign Focus Calibration System recently announced by Michael Tapes looks like a very nice and useful product.

here has been for quite a while a need for a nice, commercially-available Canon-factory style focus target system (I had to build my own).

The multiple scales of varying resolution (with a binary progression) are a very clever solution to the problem of reading the focus zone distances. If only a fine scale is provided, it may not be possible to actually read the indications at all in a situation of overall mediocre focus. If only a coarse scale is provided, it will of course not give a refined reading. The labeling of the most-coarse scale (with the least-significant digit in a very small font) is very clever.

The use of a text area as a visually-critical target to discern the plane of best focus is, in my opinion, a very valuable feature. (I have used it with great satisfaction on my own target system - added it in V 1.1).

The axis alignment system on the PRO version is very clever and should be convenient to use.

So Michael, bravo! A very thoughtful approach to a practical need, and what appears to be a nice execution as well.

And it draws upon clearly-manifest scientific principles.
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  #19  
Old December 12th, 2008, 12:35 PM
Asher Kelman Asher Kelman is offline
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Quote:
Originally Posted by Daniel Buck View Post
Doug, would you like us to stop posting? I've got no problem doing that :-) All my posts have at least been photography related, I don't introduce politics, religion, or other (what I would call 'sensitive') subjects to my postings. If being a tad bit off topic bothers you, then these announcements should be mad as locked posts, so that no discussion can happen ;-) What would you have us discuss... the release date?
Hi Daniel,

You are encouraged to post, LOL! We always need honest opinion to be realistic.

There really is an issue with focus on a lot of lens camera combinations. So a search on back or front focus and that will give an idea of the extent of the problem for camera makers. So a device for helping determine focus adjustment is worthy of discussing. The reason why MFRS have introduced micro-adjustment is because there have been thousands of returned lenses to service centers. That diverts technicians from more serious issues where parts need to be replaced. So it's more efficient for them to allow us access to this function in their firmware and have users do the work for them for free!

This matter brings into focus the general problem of have no access to firmware control of camera functions and adjustments. In the simplest case, open access might allow a bright programmer to address

assignment of focus offsets at more than one focal length for a zoom lens.

Currently Chuck Westfall of Canon says we should pick the one focal length of the zoom we use most often. Its really silly that we cannot devote 3 offsets to a a zoom where it could be relevant. For example, a 28-300 mm lens is unlikely to be perfectly adjusted with just one offset throughout its zoom range. (I am pretty certain that creative folk would discover all sorts of other useful capabilities if they could access the camera components addresses and control schemes.)

If one has no focus problems then this solution has zero value. Why spend the money? However, there are enough complaints to justify looking for ways to adjust the lenses individually without sending the lenses and camera back to the service centers to get corrected.

Asher
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  #20  
Old December 12th, 2008, 12:50 PM
Doug Kerr Doug Kerr is offline
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Quote:
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Doug, would you like us to stop posting?
No.

Best regards,

Doug
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  #21  
Old December 12th, 2008, 01:46 PM
Daniel Buck Daniel Buck is offline
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Originally Posted by Doug_Kerr View Post
No.

Best regards,

Doug
ok, just checking. Wasn't sure what you were getting after ;-)
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  #22  
Old December 12th, 2008, 03:20 PM
Bill Miller Bill Miller is offline
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Quote:
Originally Posted by Asher Kelman View Post

This matter brings into focus the general problem of have no access to firmware control of camera functions and adjustments. In the simplest case, open access might allow a bright programmer to address

assignment of focus offsets at more than one focal length for a zoom lens.

Currently Chuck Westfall of Canon says we should pick the one focal length of the zoom we use most often. Its really silly that we cannot devote 3 offsets to a a zoom where it could be relevant. For example, a 28-300 mm lens is unlikely to be perfectly adjusted with just one offset throughout its zoom range. (I am pretty certain that creative folk would discover all sorts of other useful capabilities if they could access the camera components addresses and control schemes.)

If one has no focus problems then this solution has zero value. Why spend the money? However, there are enough complaints to justify looking for ways to adjust the lenses individually without sending the lenses and camera back to the service centers to get corrected.

Asher
If you have a lens that is not focusing correctly (zoom) send it the Service center and get it right. What I fail to understand is someone willing to pay $139.95USD for a product they can obtain off the Web for FREE! That is unless they have money to burn.

Tim Jackson had a chart and instructions for a Nikon 70 in 2004, stilll works today, just not a fancy stainless ruler, but same chart. Its Free! http://focustestchart.com/

Bart van der Wolf posted a micro-adjustment tip almost 1 year ago, Its Free! http://www.openphotographyforums.com...ead.php?t=4708

When I 1st bought my 1Ds and 2 L Zooms, I found they were not focusing correct. This was 4 years ago. The answer was pretty simple, a trip to Irvine (service center) dropped them off. Went and had a great lunch in Newport returned and picked them up. Never a problem sense.

According to Canon the micro-adjustment is a feature to be used as a Temporary fix until the lens can be re-calibrated by the Mfg.
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Old December 12th, 2008, 03:37 PM
Doug Kerr Doug Kerr is offline
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Hi, Bill,

Quote:
Originally Posted by Bill Miller View Post
Tim Jackson had a chart and instructions for a Nikon 70 in 2004, stilll works today, just not a fancy stainless ruler, but same chart. Its Free!
There are those (Canon in particular) who caution against the use of a "sloped" focus indicator target without a "flat on" target for the camera (or photographer) to actually focus on.

I have not conducted any tests to ascertain how much advantage the one has over the other. I just built one with a "flat on" target on it.

I believe that there are "patterns" for that kind of target rig available on the Internet as well.

Best regards,

Doug
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  #24  
Old December 12th, 2008, 05:59 PM
Ivan Garcia Ivan Garcia is offline
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Quote:
Originally Posted by Bill Miller View Post
.....
[snip] What I fail to understand is someone willing to pay $139.95USD for a product they can obtain off the Web for FREE! That is unless they have money to burn...... [/snip]

Mmm.. well, yes you have a point. However, they are free and you get exactly what you pay for... i.e. not a very accurate product. It helps, for sure, but to achieve 100% accuracy, you need to spend a great deal of time aligning the camera and the target; even then, unless you have lasers sights.. acquiring 100% alignment would be difficult, if not near impossible.
Here, for the first time, we have a reliable, precise, and well manufactured product, which I for one will find incredibly useful. So much so, I've already placed my order.
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  #25  
Old December 12th, 2008, 07:17 PM
Asher Kelman Asher Kelman is offline
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Honestly, the LensAlignLite seems to me to be a more bang for the buck for most folk and the same sloped metal ruler. apart from missing a tripod mount, they seem to have the same function. Oh yes the Pro version is aligned on the lens optical axis by sighting from a hole in an extra siting board but the Lite version has a mirror to work from the front just as well it would seem.

Is this better than a sheet with a printed target and the camera at 45 degrees, I'll tell you ASAP.

Asher
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  #26  
Old December 12th, 2008, 08:22 PM
Doug Kerr Doug Kerr is offline
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Hi, Asher,

Quote:
Originally Posted by Asher Kelman View Post
Is this better than a sheet with a printed target and the camera at 45 degrees, I'll tell you ASAP.
Some work I did a few years ago suggested that it is not as easy to get an unambiguous focus on a transverse line on an oblique surface as we might hope. Of course this is in part a matter of the "sensitivity orientation" of the AF detector of interest (and we may well need to determine the behavior of the AF system separately for the various AF detectors, a matter that is rarely mentioned).

The most direct way to dispose of those phenomena - however serious or innocuous they may be, and we may never really know that - is to provide a base focus target that is perpendicular to the camera axis. (Again, as I have mentioned, the scheme recommended by Canon involves that, and no, I don't have any references to that recommendation - just a fairly vivid recollection.)

I'll be interested to hear the results of your own testing of that matter.

Best regards,

Doug
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  #27  
Old December 13th, 2008, 05:57 AM
John_Nevill John_Nevill is offline
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Surely, it all boils down to the operator of such tools!

MT's new Lensalign product looks good and he has great reputation for his Whibal, but the process of lens calibration is more that just pointing a camera at a target, ruler, image or well crafted piece of plastic.

I'm just not sure that £100 is justifiable when 80% of the process is manual. OK, if a solution interfaced directly with the camera through iterative methods and automatically adjusted the firmware parameters, then I would say its a breakthrough of sorts....no doubt costing many times the price.

However any process which requires human intervention, be it at set-up, interpretation, evaluation and iteration is subjectively fallible...... And for those of us who can't micro adjust, the camera still has to go back to the manufacturer.

I hope MT sells 'em by the truck load, but I'll stick with a combination of paper charts, rulers and moire images and buy another year's membership to my local wildlife trust.
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  #28  
Old December 13th, 2008, 08:35 AM
Doug Kerr Doug Kerr is offline
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Hi, John,
Quote:
Originally Posted by John_Nevill View Post
Surely, it all boils down to the operator of such tools! . . .but the process of lens calibration is more that just pointing a camera at a target, ruler, image or well crafted piece of plastic.
Quite so. (By the way, it's not "lens calibration" that we are necessarily working with here - rather, "AF system calibration with a certain lens in the chain".)

I think it is important to note that the possible benefit of any focus testing target is not limited to the exploitation of camera "AF trimming" facilities (although that certainly raises the level of interest).

Many people are intersted in testing the AF performance of their camera/lens combinations, even if only to decide whether to send their gear in for factory recalibration. I don't yet have a camera with AF trimming, but I certainly use my focus test target assembly from time to time.

And, just as with the other situation, doing this requires attention to detail as well. And some users aren't up for that either.

Of course, how much any user wishes to spend on a tool for doing so is subject to many considerations.

An alternative (especially if the camera is still under warranty) is to send it to the factory service center with a note saying "I'm not sure the AF accuracy is up to spec." With the cost of shipping, insurance, and so forth, one can probably do that for about USD25.00. And get your camera back in just a few weeks.

Best regards,

Doug
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  #29  
Old December 14th, 2008, 01:14 PM
Michael Tapes Michael Tapes is offline
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Hello to all,

Disclaimer: This post is kind of a stream of consciousness. Read at your own risk <g>.

For those who may not know, I am the designer of LensAlign™. I am not here to sell or promote LensAlign, just to explain its rational of development. I feel that it is a valuable product that is cost effective for a large number of photographers, both Pro and enthusiast. If you fall into that category, then great, please buy one. If you do not feel that way, then your money is miss-placed in the purchase of a LensAlign.

Let me address some earlier statements as a guide to my comments.


Quote:
If you have a lens that is not focusing correctly (zoom) send it the Service center and get it right.
The majority of people must pack and ship their equipment back to Canon (or Nikon or who ever). This has time, risk, and money implications for the camera owner. Risk of loss or damage, PITA to pack it all up, write up the explanation, expense to ship it to the service center, and the opportunity loss (whether it be artistic or commercial) of being without the equipment for generally what I believe to be 7-10 days plus or minus, but many times longer and/or mutliple times back and forth.

IMO that makes the decision to sent it back quite important. One would not want to do it if the camera (I will use the word camera meaning camera/lens combo that is in question) was working properly and the problem being caused by user error, or inexperience, etc. Also the documentation of back/focus issues is not a science and many time the camera will come back with the words "no problem found", yet there is still a problem. Or after minutes or hours on the phone with the company, they tell you to send back just the camera body, and after review they ask you for the lens as well. Or all of your bodies and lenses.

In light of the above, one of the goals of LA (LensAlign) was to provide a common "reference", such that a user could document their problem via the use of LensAlign (which allows a standardized test shot to be taken), and the service center would know the conditions of the test, and/or use LA to duplicate the result or show otherwise.


Quote:
What I fail to understand is someone willing to pay $139.95USD for a product they can obtain off the Web for FREE! That is unless they have money to burn.
IrfanView is a terrific FREE image editor, as is FastStone, as is Picasa, yet there are 100s of commercial image editor/viewers that are available commercially and that people buy. If the free solution works for someone then they are set. End of discussion. If they seek more or even ONE specific feature offered by the commercial product, then they might invest the $$. Just because a free product exists is not reason that the marketplace does not have room for or even desire a "better" commercial product. And the criteria of the free product is not simply that IT WORKS. People want choice, and clearly LA offers much that the free solutions do not, but again, that is to be judged by the potential buyer.


Quote:
Tim Jackson had a chart and instructions for a Nikon 70 in 2004, stilll works today, just not a fancy stainless ruler, but same chart. Its Free! http://focustestchart.com/
Yup. I especially like Tim's thorough write up, but some of his assumptions are not correct IMO, and also the test is not highly repeatable across time, and users. That is not to say that someone could not get a proper result, just that it does not constitute a standard reference, that lends itself to repeatability, and ease of use.

I would also point you all to an even better free "chart" solution developed by Jeffrey Friedl:

Jeffrey’s Autofocus Test Chart

JF took all of the previous art, including Tim Jackson's (with proper credit) and made what he thought was an even better embodiment of Tim's chart (and of course Tim was not the first and only chart system. He just did the best documentation and explanation, which was and is great!). JF documented his entire process and rational, and IMO is the best of the chart based systems. But as you read in his assessment, even *he* found issues with his own work, but based on the DIY philosophy cut it short once it met his immediate needs, writing that an even better solution could and should be created.

Quote:
Bart van der Wolf posted a micro-adjustment tip almost 1 year ago, Its Free! http://www.openphotographyforums.com...ead.php?t=4708[/COLOR]
When I saw Bart's innovative technique, I was quite intrigued and impressed with this first really novel approach to the front/back focus issue. It will certainly work, and is free, but I found the process lacked in a few areas, especially in not being able to view the lens DOF at a specific set of test parameters. The DOF readout of the chart or LA ruler or other home brew method is critical to assessing the full picture. But again, Bart's method was novel, creative and will certainly allow you to accurately set the AFMA (auto focus micro-adjustment Adjustment).


Quote:
When I 1st bought my 1Ds and 2 L Zooms, I found they were not focusing correct. This was 4 years ago. The answer was pretty simple, a trip to Irvine (service center) dropped them off. Went and had a great lunch in Newport returned and picked them up. Never a problem sense.
Great solution in your situation. We are all envious. And I used to spend a lot of time in Newport in the 70's and then again in the 90s. Nice area.


Quote:
According to Canon the micro-adjustment is a feature to be used as a Temporary fix until the lens can be re-calibrated by the Mfg.
I have not seen this statement, but I will note in agreement, that up until Chuck Westfall's recent Dec Tech Talk column, nothing has been forth coming from the camera makers, and Chuck's statement was specifically not Canon policy. However, I believe that the camera makers are trying to unburden their service centers from dealing with those customers who can satisfy the focusing needs via the AFMA. What is missing is the common reference, so that a standardized test can be established. LA can fill that need if enough people adopt it.

Chuck has been aware of my development efforts from the beginning, and gave me some good insights as to Canon requirements, and of course those are incorporated into LA. However, just to be clear, that is not meant to be an implied endorsement, but obviously Chuck felt confident enough in my work to mention LA as something to look at in his recent column. But again in full disclosure, Chuck has only seen videos, and simulations, and result photos from the device. Only now is Canon looking at the final production version.

I also shared my 3D modeled simulations (very accurate and cool, I might add), with other camera makers and other highly noted professionals in our field for their feedback and comments. And of course did some prototype testing with them as well. All in all we went through about 15 prototypes, ranging from fully machined, to cut from cardboard.

My simply goals in the creation of LA:
  • Quick
  • Easy
  • Accurate
  • Users can get it right
  • repeatable
  • create a photo database of camera/lens AF performance
  • profit
  • fill a need in the community
  • more..but getting tired <g>

I am not afraid to list profit as a motive of development. I suspect that we all do something in our lives and expect others to pay us for our time, service, or product. And with product it is easy, the customer evaluates, reads others experiences with the product, and make a decision. So pricing is determined by the marketplace. If LA is priced too high, then it will fail at that price. If it is priced too low, then I will not be able to sustain the business model and I will go out of business.

Last notes while I think of them (for those who have not fallen asleep)...

In terms of prior art and my sequence of design.

When I began the project I was aware of several chart type designs, including TJ which was kind of for Nikon people, and a Canon people chart, that had you cut out a cardboard house to sit on the angled chart to create a perpendicular focus target. So I was aware of the chart method. Seeing that a "better" solution was required for it to meet my goals of accuracy, speed and repeatability, I proceeded on my design effort.

Bart published his method (very impressive as I said), and I evaluated carefully, but saw that as clever as it was, it did not fulfill the same nitshce as I was trying to fill. So I continued.

Late in the process, I came upon JFs work and was also impressed with how he had documented the situation from his perspective. And so I sent JF my then current prototype (Aluminum and stainless steel). He has been very helpful since then, and while I did not use any of his prior art directly, I was definitely influenced by his work.

Once the final design was finished I contacted Bart, to see if he was interested in critiquing my work. He was and I shared my work with him in the form of videos and discussion. My hope was for him (as well as all of my other "helpers") to poke holes in my design. He was unable to (except for one minor tangential aspect, that I am confident is correct). But he reserves judgment until his unit arrives this week.

So that is some of my story. Obviously Michael Reichmann(LL) and Dave Etchels and crew(IR) have been in the loop.

LL hands-On
IR Hands-On


And about 2 weeks ago Asher joined our internal mail-list and he gushed with enthusiasm and support, asked some pertinent questions as only he can do. His Hands-On Report based on his eval unit are due any day. I have no idea how he will react to using LensAlign, but I am sure that it will be helpful, fair, insightful, and intensive. I always appreciate his insights and perspective.

So I had a lot of help from staff and peers for which I am grateful.

If you have made it this far I thank you for your interest. I will read any comments with interest and appreciation.

If I do not post further, that just means that I did not post further.*

*A paraphrase from the Van Morrison song Domino.

Michael Tapes
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  #30  
Old December 15th, 2008, 09:39 PM
Doug Kerr Doug Kerr is offline
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Regarding the matter of using just an angled test target for AF testing, I happened to run into this from Chuck Westfall of Canon in his Tech Tips column in The Digital Journalist for December 2008:

• Do not attempt to autofocus on an angled chart, because doing so will degrade the consistency of the camera's focusing measurement. Keep in mind that the camera's AF sensor is comprised of multiple pairs of linear pixel arrays. If you attempt to autofocus on a single line in an angled focusing chart, only a few pixels from each active pixel array will "see" the target. Ideally, the contrast in the reference target should cover the entire area of the camera's center focusing point, and the reference target should be perfectly parallel to the camera's focal plane.

This is consistent with Canon recommendations I had seen in the past.

Here is the link to Chuck's column:

http://www.digitaljournalist.org/iss...tech-tips.html

Best regards,

Doug
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