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Tamron TapIn console
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Feb 18, 2020 16:58:44   #
mwsilvers Loc: Central New Jersey
 
Magaliaman wrote:
Short Version........

Setup your calibration Target @ just under 1.5'
Set your lens to 18mm (Micro Adjust here)

Now set your target at 8'
Leaving the lens still at 18mm (Micro Adjust here)

Now set your target to Infinity
Leave the lens at 18mm (Micro Adjust here)

Now repeat at 35mm, 50mm, 70mm etc

Very Time Consuming

The thing to consider is: your not necessarily trying to get the sharpest image possible, You cannot make your lens sharper than the optics allow. you're trying to zero in on front or back focus issues.

I Hope this helps some.
Short Version........ br br Setup your calibratio... (show quote)

Correct. In addition calibrations made at any one distance, especially if very large, can also have a noticable affect on the sharpness of images already calibrated at the closest distances to it. That makes the process more complex because the various settings can interact with each other, and this interaction also includes the adjustments made at various focal lengths. In other words there are not 24 discreet adjustments for the 18-400 lens. There is a certain amount of overlap between the adjustments. Fine tuning when the results of multiple settings noticeably overlap can be very time-consuming and may require some compromise. The issues and difficulties are very similar to the tool used for Sigma lenses.

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Feb 18, 2020 17:36:45   #
fotobyferg
 
mwsilvers wrote:
For each of the 8 focal lengths at the left you need to test at 3 distances from your target subject.

In the first column for 18mm your result indicates that you tested shooting at a subject 1.48 feet away from your camera's sensor and that +10 gave you the sharpest output. You need to perform the test again for the second column at a distance of 8 feet from your camera sensor, and in the third column you need to shoot at a target at infinity.

And, of course, you need to do the same tests at those three distances for the other 7 focal lengths.
For each of the 8 focal lengths at the left you ne... (show quote)


Logically, that is what I figured, but the images appeared to be too blurry to make an accurate determination of front or back focusing. This was what was confusing me. I use this lens for rugby, and get decent results...so how could it be so wonky at the 8’ and infinity setting. I figured I *must* be doing something wrong.

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Feb 18, 2020 17:37:31   #
fotobyferg
 
Magaliaman wrote:
Short Version........

Setup your calibration Target @ just under 1.5'
Set your lens to 18mm (Micro Adjust here)

Now set your target at 8'
Leaving the lens still at 18mm (Micro Adjust here)

Now set your target to Infinity
Leave the lens at 18mm (Micro Adjust here)

Now repeat at 35mm, 50mm, 70mm etc

Very Time Consuming

The thing to consider is: your not necessarily trying to get the sharpest image possible, You cannot make your lens sharper than the optics allow. you're trying to zero in on front or back focus issues.

I Hope this helps some.
Short Version........ br br Setup your calibratio... (show quote)



Logically, that is what I figured, but the images appeared to be too blurry to make an accurate determination of front or back focusing. This was what was confusing me. I use this lens for rugby, and get decent results...so how could it be so wonky at the 8’ and infinity setting. I figured I *must* be doing something wrong.

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Feb 18, 2020 17:51:24   #
Magaliaman Loc: Magalia, CA
 
fotobyferg wrote:
Logically, that is what I figured, but the images appeared to be too blurry to make an accurate determination of front or back focusing. This was what was confusing me. I use this lens for rugby, and get decent results...so how could it be so wonky at the 8’ and infinity setting. I figured I *must* be doing something wrong.


What are you using for a calibration target?

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Feb 18, 2020 17:59:30   #
fotobyferg
 
The first shot is @ 8’, the second more towards infinity. Others are just random shots using the lens that happen to be on my iPad.


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Feb 18, 2020 18:01:30   #
fotobyferg
 
Magaliaman wrote:
What are you using for a calibration target?


Lens Align kit on tripod.

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Feb 18, 2020 18:03:20   #
Magaliaman Loc: Magalia, CA
 
fotobyferg wrote:
The first shot is @ 8’, the second more towards infinity. Others are just random shots using the lens that happen to be on my iPad.


I Dont think thats going to "Get it" You need something that can measure focus much much more accurately. Heres a link to an example target.

https://www.bhphotovideo.com/c/product/970599-REG/lensalign_la_la2_mkii_focus_calibration_system.html/?msclkid=bfdf1f08905e1d5818804144fceb0e54

By no means is this the only target to use, but rather an example of what you need.

-Gary

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Feb 18, 2020 18:07:37   #
fotobyferg
 
Magaliaman wrote:
I Dont think thats going to "Get it" You need something that can measure focus much much more accurately. Heres a link to an example target.

https://www.bhphotovideo.com/c/product/970599-REG/lensalign_la_la2_mkii_focus_calibration_system.html/?msclkid=bfdf1f08905e1d5818804144fceb0e54

Bu no means is this the only target to use, but rather an example of what you need.

-Gary

That’s exactly the one I have.

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Feb 18, 2020 18:09:14   #
Magaliaman Loc: Magalia, CA
 
fotobyferg wrote:
Lens Align kit on tripod.


Okay sorry......... I thought the example pics you posted was what you're using. My Mistake.

Theres a lot of things that contribute to a less than razor sharp image. Although what you posted seems fine, I would go thru the whole calibration sequence at all focal lengths and ranges, then see what the lens produces. Time consuming yes. But worth it in the long run.

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Feb 18, 2020 18:22:05   #
fotobyferg
 
Magaliaman wrote:
Okay sorry......... I thought the example pics you posted was what you're using. My Mistake.

Theres a lot of things that contribute to a less than razor sharp image. Although what you posted seems fine, I would go thru the whole calibration sequence at all focal lengths and ranges, then see what the lens produces. Time consuming yes. But worth it in the long run.


Yep, I think I’ll call Tamron first to see if they can shed any light on why the pictures taken with this lens are reasonably sharp (oh wait...the first was with a 90mm, my bad) and why I can’t seem to get an image with the calibration kit (as per the original post image) where the center and third column distances result in an image clear enough to determine if the lens is back or front focusing at those distances.

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Feb 18, 2020 18:27:23   #
Magaliaman Loc: Magalia, CA
 
fotobyferg wrote:
Yep, I think I’ll call Tamron first to see if they can shed any light on why the pictures taken with this lens are reasonably sharp (oh wait...the first was with a 90mm, my bad) and why I can’t seem to get an image with the calibration kit (as per the original post image) where the center and third column distances result in an image clear enough to determine if the lens is back or front focusing at those distances.


Just a thought.... You dont have the focus limiter switch set wrong do You ? It might be limiting the range that the lens will focus at

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Feb 18, 2020 19:03:16   #
fotobyferg
 
Magaliaman wrote:
Just a thought.... You dont have the focus limiter switch set wrong do You ? It might be limiting the range that the lens will focus at


No focus limiter on this lens.

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Feb 18, 2020 19:17:40   #
Magaliaman Loc: Magalia, CA
 
fotobyferg wrote:
No focus limiter on this lens.


Then I'm all out of ideas. Calling Tamron seems like the logical choice at this point.

Sorry

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Feb 18, 2020 20:00:15   #
fotobyferg
 
Magaliaman wrote:
Then I'm all out of ideas. Calling Tamron seems like the logical choice at this point.

Sorry


Thanks for trying. Hopefully Tamron will have some suggestions.

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Feb 19, 2020 07:44:13   #
dogman24
 
mwsilvers wrote:
If, as you indicated, you have very little patience, then calibration is most likely not for you. All that detailed instructions or even a video will do is give you a better understanding of how the process works. However it is unlikely to speed up the process, and it will not be a magic bullet that will easily and quickly allow you to calibrate your lenses.

Calibration requires a lot of discipline. You need to perform multiple structured tests and observations for each of the large number of focal lengths and distances available for zoom lenses. You need an appropriate target and must test at various defined distances depending on the focal lengths used by the tap in. And you need to be able to get repeatable results which means multiple tests.

The testing process is arduous, and time-consuming, and tests should be performed on a tripod using the viewfinder. That is an important factor because calibration issues are more often a result of using a camera's AF sensor through the viewfinder rather than the camera's main sensor which is used in Live View. It is a process not meant for the faint of heart. It can take a number of hours of intense effort to calibrate a single lens.

A very important consideration is that when using the Tap-in device you are calibrating the lens itself by modifying it to work optimally on your specific copy of your camera model. That means it is more than likely that the lens will not work as well on any other camera you put it on, including copies of your camera. As a result, if you put it on another body you will mostly have to reset the lens back to its factory defaults, and recalibrate it.
If, as you indicated, you have very little patienc... (show quote)


Does Tamaron (or an alternate source) provide a service to calibrate their lenses? And if so, any idea as to the charge?

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