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Author Topic: My Review of the Reikan Focal Pro Lens Microadjustment System  (Read 25099 times)
BartvanderWolf
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« Reply #40 on: June 02, 2012, 06:55:25 PM »
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The significance of this advantage (or the significance of focus tuning in general) is debatable, of course.

Hi Julian,

Not really debatable. A properly acquired average has its benefits.

However, it's not clear how the additional samples for a given situation are taken by the software. Just taking additional samples is not going to address the fundamental issue of hysteresis. There is a difference between approaching the Phase detect focus position from the minimum focus distance and approaching it from the infinity distance direction. For some lenses that difference is very significant, even switching the focusing direction by one notch may introduce a significant focus error.

Cheers,
Bart
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julianv
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« Reply #41 on: June 03, 2012, 12:31:38 AM »
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Not really debatable. A properly acquired average has its benefits.

I don't think FoCal is choosing the average of the multiple measurements at each AF Fine Tune (Microadjust) setting. In the plots, each measurement point is shown as a green or blue diamond.  A red dot is drawn over the "most likely correct" point, according to the documentation.  In the plots that I have seen thus far, this is not always the average, or best result point.  I don't know how the algorithm chooses the points used for its curve fit.  You can see three of the plots made for my Nikkor 24-70 in this gallery.

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However, it's not clear how the additional samples for a given situation are taken by the software. Just taking additional samples is not going to address the fundamental issue of hysteresis. There is a difference between approaching the Phase detect focus position from the minimum focus distance and approaching it from the infinity distance direction. For some lenses that difference is very significant, even switching the focusing direction by one notch may introduce a significant focus error.

In the "Pro" version of the program, you can choose the defocus operation that is used before each measurement. It defocuses by changing the Fine Tune value to its near or far extreme values, or by physically moving the lens focus setting to near or far extremes. But, in an automated sequence, the same defocus method will be used for all points. It might be more realistic to use a randomization of initial positions.

When I wrote that the significance of the fine tuning process is debatable, I was really thinking about the practical benefits and limitations. For some lenses (especially zooms) the optimum adjustment value can vary with focal length, or subject distance, or possibly even aperture.  The user needs to choose a compromised value for the lens, or needs to reload different values depending on situation. Even with prime lenses, the magnitude of the improvement obtained from AF tuning may not be significant for some users.  Inexperienced users might tweak their lens for best results at one focus distance, without realizing that they worsened the performance at other distances.

But for those who stand to benefit from AF fine tuning, I think FoCal represents a genuine advance over tools like LensAlign and SpyderLensCal. The product is still a bit unrefined, but the developer has obviously put a lot of thought (and work) into it.
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jrsforums
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« Reply #42 on: June 03, 2012, 06:15:33 AM »
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With all due respect, I didn't interpret the posts by Ellis as bad mouthing.  To me, it seems his concerns were pretty well limited to privacy issues, so perhaps our interpretations differ.  So be it.

Glenn

The "privacy issue" is what it has boiled down to.  Had that been it, I would never had made a response as I respect his right to his concerns, even if I do not hold them.

Re-read his earlier posts.  After reading one limited review, he immediately, in multiple posts, panned the product, the need for the product by a photographer, and, via the orator's questioning method, the functionality of the product.  All this with, apparently never having tried the product or looked over any of the available material on the product and reviews by others.

As I said in an earlier post....Ellis is a respected member of this forum and the photographic community.  I expect that many take his view as "gospel".  As such, I expect his critique of a product to be held to a higher standard, which was not seen in this thread.
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Keith Reeder
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« Reply #43 on: June 03, 2012, 07:19:05 AM »
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Ellis' comments were overly dismissive for no good reason - unfounded concerns about privacy (how much intrinsic value does a camera serial number really have, except to the owner of the camera?) are one thing, but that one silly niggle became the basis (or rather the excuse) for condemnation of the application and the entire rationale of its creation and development.

I mean, seriously?

Quote from: Ellis Vener
Beyond making sure your camera is focusing where you think it should be focusing, can any of those analysis tools actually make you a better photographer or make your photographers better in any meaningful way? People spend far too much time measurbating already and then arguing about their findings as it is.


We all know that in many (most?) photographic genres sharpness is of crucial importance to the perceived quality of the end result, and FoCal directly addresses that fact. Ellis' references to Capa's and Cartier-Bresson's work are entirely irrelevant to the legitimate desire of photographers to have their equipment performing at its best.

But the key point here is that Ellis clearly made his decision about FoCal in a complete information vacuum - his subsequent comments and questions demonstrate a complete ignorance of the application, entirely incompatible with the self-important and condescending way in which he dismissed it.




« Last Edit: June 03, 2012, 07:23:25 AM by Keith Reeder » Logged

Keith Reeder
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« Reply #44 on: June 03, 2012, 09:09:15 AM »
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We do lens alignments here at the shop, and 75% of the bodies that are brought in have a problem.  It normally isn't a lens thing, it's a sensor plane thing.  We can put the same lens on 3 different bodies and will get 3 completely unrelated results ... one body front focus, one back focuses, one pretty good.

If it were a problem with the camera alignment only, then one could use the same adjustment for all of one's lenses. In practice, different adjustments are needed for various lenses used on the same camera, indicating that the lens is also a factor.

Regards,

Bill
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Ellis Vener
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« Reply #45 on: June 03, 2012, 01:18:55 PM »
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Dear Keith Reeder ,
 Please re-read what I have written: I never condemned or dismissed the software.  I am not ignorant of how it works or what it does. I criticized one aspect of the licensing scheme Reikan  currently implements. It may be a "silly niggle" for you but it is not for everyone.

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Ellis Vener
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jrsforums
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« Reply #46 on: June 03, 2012, 05:33:17 PM »
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Dear Keith Reeder ,
 Please re-read what I have written: I never condemned or dismissed the software.  I am not ignorant of how it works or what it does. I criticized one aspect of the licensing scheme Reikan  currently implements. It may be a "silly niggle" for you but it is not for everyone.



Hmmm..??

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Based on your review, I'll pass.

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Beyond making sure your camera is focusing where you think it should be focusing, can any of those analysis tools actually make you a better photographer or make your photographers better in any meaningful way? People spend far too much time measurbating already and then arguing about their findings as it is.

Make pictures, not measurements.

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I think a photographer's time is generally better spent making themselves aware of  the interaction of color and light, framing and composition, working on seeing life , and their shooting technique as opposed to dwelling on the aspects this program seems to measure. Between two photographs of equal power the more technically refined photograph may be technically better but a technical quality is only worthwhile if it backs up a photograph  that is emotionally expressive, expresses a strong idea, and a strong aesthetic sensibility behind it. This is true for all of the arts, not just photography.

I've seen musicians, painters, and writers - as well as photographers - all get tangled up in the seductive mechanics of craft and lose sight of the bigger thing they are trying to get done. I am not immune to this myself. But I'd rather make something a little ragged and right than perfect and dull. Of course if you can get your art technically perfect and with expressing great feeling, embodying a powerful idea, and beautiful that is an unstoppable combination: Coppola's "The Godfather Part II" for example.

AND...

You never get a second chance. never, ever.
But see Robert Capa's photographs of the D-Day landings  as well as more than a little of Henri Cartier-Bresson's work as an antidote to thinking that '"There is nothing worse than a fuzzy image of a sharp concept"

Technique is the cart, it isn't the horse.

Put the viewer first.

And if you think you're making pictures  too flawed for you to live with,  toss them.

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To be perfectly clear: I am not advocating not adjusting your camera's focusing mechanisms to perform optimally.

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No. (in response to: So what you were just ranting ? I didn't think you were a ranter Ellis......altough I agree with what you said. I like this system....I don't like teching out .... with this system I can just let it do it's thing and then go about my businessess making pictures.

My objections  Does  this system have a method of ensuring your camera is square to the target?

If it does, great. If not it is a no go.

The  initial review I responded to says no hardware is needed beyond maybe a tripod. But you need a printer or access to one to print the target.

Another member of this thread said to look at the other things this software can do. Okay great: what exactly will do with that data?

The thread starter failed to mention that you are required to register your cameras including serial numbers with the software maker. Why? I see no compelling technical reason they need that information. What are they going to do with it? Who will have access to it? Why is he collecting that information? It might help his business model but there is no value in that for me.

I absolutely believe that tuning a camera's AF performance to specific lenses is critical. I do not believe this is the right product for doing that.

I'd like to see a more critical evaluation of the product before spending money on it. No tool is perfect.

Ellis....you can read it your way and I'll read it mine.

In my view, you dismissed this software and had absolutely no....or at least very limited... idea of how it worked....and at the same time condemned the need for it.  It was not until I and others responded that you fell back to the licensing as the major issue....which it may be to you...your choice...but not a reason for you to attempt to influence others not to use or try it.
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Keith Reeder
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« Reply #47 on: June 04, 2012, 06:41:57 AM »
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In my view, you dismissed this software and had absolutely no....or at least very limited... idea of how it worked....and at the same time condemned the need for it.  It was not until I and others responded that you fell back to the licensing as the major issue....which it may be to you...your choice...but not a reason for you to attempt to influence others not to use or try it.

This.

Sorry Ellis, but I don't get any sense that you generally struggle accurately to communicate your meaning when you post.

Here, your unambiguous contempt for the application fairly leaps off the page.
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Keith Reeder
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Wayne Fox
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« Reply #48 on: June 21, 2012, 01:19:09 PM »
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I have spent some time testing the FoCal software.  Because I made some comments earlier in I would add a summary of my experience/opinion.

There are a couple of issues.  It is the responsibility of the tester to insure the camera sensor and target are as parallel as possible.  While I've found it isn't ultra critical (an inch or two), a few inches off line does affect the outcome.  This isn't too challenging to over come, placing a small mirror on the target when positioning the camera, allows one to fine tune the camera position quite accurately.  Not as elegant as the LensAlign, yet not too difficult to overcome.  Printing your own target means you need a good printer with MK ink.  I used my 11880 on Epson premium presentation paper at 2880.  The resulting  target was sharp and worked well. 

At this point I've worked extensively with a d800e, a 5D Mark 3, and a 5D Mark 2.  I have a d700 and a D4 coming in, but I don't think they will change my perspective.

As far as the d800e, I don't think the software can handle the moire when analyzing the target.  On nearly every lens the setting chosen was off by as many as 7 or 8 points.  It sees the moire as lack of sharpness.  However, by clicking on the focus points in the analysis, it was pretty easy to find which was the sharpest, so I used the software in the manual mode, and I think it was easier to use than when I tried the lens align.  The issue with d800e for me so far is I just haven't tested any lenses that can resolve anywhere close to the sensor wide open, soeverything is blurry.  With the lens align it's difficult to decide which area is "less" blurry.  I found it easier to calibrate the d800e by shooting a target which had some other information such as images which didn't show the moire problem.  Also it was interesting to see how quickly diffraction affected moire (by f/11 with 3 different lenses most of the moire was gone).

The 5D Mark3 was much easier to use, but it it isn't totally automatic.  Some of the canon's are fully automatic, start the test, come back 5 minutes later.  This was the case with the 5D mark 2. What I did find was using the recommended setting wasn't always the setting I would choose.  When you examine the data you can see the results of any shot by clicking on the diamond and visually compare it to the selected setting/shot.  With the 5D Mark2 and the Canon 100mm macro, the software recommended a setting of -3, but visually it was obvious that a setting of -6 yielded the most accurate focus. The difference was at -3 the point spread was much tighter, where as at =6 there were a couple of results worse than -3 but several that were better.  So one caveat I would make is that after you complete the test, you visually examine the charts and compare the various points with the recommended/selected one.  On the 16-35 mm, the software nailed it (and it was significant, -13).  It also did so on the 70-200.  The 100mm Macro is a pretty old lens, and showed by far the most deviation in focus.

I found the f/stop range test very interesting, and it was useful in determine the minimum/maximum values for optimum sharpness. On the 5D Mark 2, all 3 lenses were better stopped down, and at f/11 diffraction had very little impact.  After that it became obvious and by f/22 things were a complete blur.  I'll be testing this out with the d800 as soon as I can get my hands on one.

As far as the licensing, personally I find it reasonable and not an issue.  You are allowed to enter 5 serial numbers for cameras, and you are allowed to make changes to your serial number list 10 times.  The change is a matter of logging onto their website, making the changes to the numbers, and then copying and pasting the resulting code back into the software.  It only takes a couple of minutes, and seems a very reasonable method to prevent abuse (say a camera club buying one copy and then calibrating everyone's camera.)  For around $400, you can license it to a CPU rather than camera bodies, and then there is no limit to the cameras.  I believe just like bodies, you are allowed to change the link to the CPU a few times.

I ran the latest beta version of their software on a Mac using Parallels/Windows 7.  I had no issue with the USB cable supplied with the d800e or with USB for the Canons.

The concept seems well thought out, the feedback is excellent and the algorithms to analyze the data seem to work pretty well for the most part.  When they don't the visual feedback is useful and works.  I found I could calibrate the 5D Mark 2 in less time than the Lens Align, and personally believe I have more confidence in the results. Most where quite similar to the same setting as with LensAlign, but most were a point or two different.

All of this is of course just my humble opinion, your mileage and opinion certainly might be different.
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Ellis Vener
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« Reply #49 on: June 21, 2012, 04:04:11 PM »
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Wayne, thank you  for that unbiased and balanced assessment of the FoCal Pro.
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Ellis Vener
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julianv
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« Reply #50 on: June 21, 2012, 05:54:36 PM »
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Very useful comments, Wayne.  I encourage you to communicate your findings to Rich, the developer of FoCal.  He is very receptive to constructive feedback.
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David Good
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« Reply #51 on: June 22, 2012, 06:01:30 AM »
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Very useful and informative post Wayne. I have been considering this software for a while and appreciate the straight forward feedback.
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tektrader
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« Reply #52 on: June 26, 2012, 08:09:06 AM »
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I was going to buy the software, BUT I noticed the Nikon D800 requires manual intervention to calibrate.

If that is so is there any advantage in paying extra for the pro version or essentially as we are losing the auto cal function is it worth paying the extra for the pro version?
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Moreno Polloni
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« Reply #53 on: June 26, 2012, 12:21:31 PM »
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I was going to buy the software, BUT I noticed the Nikon D800 requires manual intervention to calibrate.

If that is so is there any advantage in paying extra for the pro version or essentially as we are losing the auto cal function is it worth paying the extra for the pro version?

That's what I thought and I picked up the standard version, which turned out to be a mistake. Regardless of the product description here's nothing semi-automatic about it. You have to manually click through a bunch of focus settings on a trial and error basis, which I found to be unreliable and ambiguous. After a few frustrating hours of trying the software I'm no farther ahead than before.

If you're interested in the software I'd suggest you go for the mid or Pro version, as these will run in semi-automatic mode. When you start the test the process is automated on the D800 with the exception of having to change the AFMA settings manually several times.
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tektrader
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« Reply #54 on: June 27, 2012, 05:51:59 AM »
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Thanks Moreno, I bought the PLUS version.  Also thanks for the discount  link on the previous page. Saved me money. Smiley
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hilong
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« Reply #55 on: February 19, 2013, 06:00:28 PM »
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Thanks Wayne & Alan for the great insight as to FoCal's usefulness. I've been going crazy trying to get my 7d & 5dIII optimized & this is the only program that attempts to eliminate the user interface (as much as possible) and includes a AF repeatable element. I've seen images that George Lepp did and shows off the 7d's sharpness by blowing up an image & I've never been able to come close to that standard. I've made certain to work camera shake and DOF f stop settings attempting to get standard setting sharp images, which is most of us want. Other processes of lens/body calibration don't appear to look at any form of repeatability. I've sent lenses to Canon to be calibrated & or bodies and they have met specifications, then when combined don't produce a quality image. Both were stacked in the opposite direction of allowable tolerance. I'm looking forward to the Mac version of this to come out and give it a go! 
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jrsforums
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« Reply #56 on: February 19, 2013, 06:13:29 PM »
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I believe the Mac version is out
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« Reply #57 on: February 20, 2013, 02:31:00 AM »
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I believe the Mac version is out

Correct. It was released at least four months ago.

Jeremy
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texshooter
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« Reply #58 on: July 05, 2013, 11:02:30 PM »
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Don't let what happened to me happen to you. I don't know if it's due to my camera limitation or a Focal software limitation, but you might get Auto Focus Manual Adjustment (AFMA) recommendations from the software that make no sense whatsoever. For example, see the Reikan Focal AFMA chart below for my 70-200mm f2.8 L  MarkI lens @200mm. The software calls for an 8.0 AFMA. So I set my camera to +8.0 and went on a sightseeing day trip. When I got back home I noticed all me photos where back-focused. So I ran a few tests without the software, just using my eyeballs and a sharp stationary object, and learned that my lens required no AFMA, contrary to Focal's calculation. Had I looked at  this chart more closely I would have noticed that the camera achieved the most sharp image at AMFA 0.0. That should have been a clue that the software was wonked.
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jrsforums
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« Reply #59 on: July 06, 2013, 07:06:11 AM »
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Don't let what happened to me happen to you. I don't know if it's due to my camera limitation or a Focal software limitation, but you might get Auto Focus Manual Adjustment (AFMA) recommendations from the software that make no sense whatsoever. For example, see the Reikan Focal AFMA chart below for my 70-200mm f2.8 L  MarkI lens @200mm. The software calls for an 8.0 AFMA. So I set my camera to +8.0 and went on a sightseeing day trip. When I got back home I noticed all me photos where back-focused. So I ran a few tests without the software, just using my eyeballs and a sharp stationary object, and learned that my lens required no AFMA, contrary to Focal's calculation. Had I looked at  this chart more closely I would have noticed that the camera achieved the most sharp image at AMFA 0.0. That should have been a clue that the software was wonked.

If you have read Roger Cicala's LensRental blog, you understand that Phase Detection AF is not exact....it is more of a shotgun clustering.

As you can see, The FoCal software attempted to fine the center of the cluster that it saw.

Whenever I have had "strange" results with a quality lens like the one you were using I have always been able to trace it back to my "pilot error"....such as leaving the IS on, not having the target properly lighted, tripod, etc. not stable, not using a cable release, moving in the room while auto AF going on, etc.
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