DotTune AFMA (dot_tune.mo)

[Manofmayo]

I have a question about repeatability.   I ran DotTune for my Sigma 20 Art 5 times, refocusing each time, and I got values of -6,+10,-4,-5 and -15.   Throwing out the high and the low, that makes for a AF tune of -5.   I did the same thing with the Canon 35 IS and the Canon 50 1.4 and had a much large range of values (mostly between -10 and +10).   Does this make sense?

I used MF, One Shot, wide open with exposure +2/3, in a bright room with a target 2m away.

I would expect repeatability to be within 5 units each time (or a max range of 10).

[russellsnr]

Hi, Just tried Dot Tune with my 6D after watching available videos.
When I start the operation the screen on my 6D goes black the SD card shows activity via the red light flickering and then I get with some lenses a result others not so but my question is "should I be seeing the the active screen working" IE shows the passes 1 to 4 or is the blank screen now the way it goes? Thank You.

[a1ex]

If the display is not on, dot_tune attempts to press INFO/DISP a few times. If that doesn't turn on the display, the calibration process refuses to run.

If you get different behavior, that's a bug.

[Marsu42]

I did the same thing with the Canon 35 IS and the Canon 50 1.4 and had a much large range of values (mostly between -10 and +10).   Does this make sense?

Nope - with my dot_tune experiments, everything worked as expected and the differences were in the +-2-range. The main source of error course is the distance to the target, but if that's fixed it should work.

[russellsnr]

Hi, Tried again, the D/T works on the 6D but the screen is blanked out until finished then comes up to show the adjustment also the adjustment shows in the camera so as not a whiz on this I assume the calibration has been done correctly. Thanks. Russ

[a1ex]

Does the screen turn off when you press the shutter halfway? If yes, that should explain the behavior.

[groundlessfears]

hi, i have tuned my Tamron 24-70 f2.8 vc lens and i got -5 and -15 but, its giving better focus now, but can anyone suggest the distance to the subject so i re tune the lens more accurately.? both wide end and tele end distance..

[nikfreak]

You could try to calculate an average value for both the wide and tele end if you have some luck. Probably dottune will spit out different values depending on the distance to your object. The ambient light will affect your results, too.

Now if you have luck and done all your tests you might want to calculate an average value. Makes ofc no sense if for e.g. on wide end you get let's say -5 for 1meter distance and have -15 for 3meter distance. But if it's like -5 and -7 and -6 then you could average it to -6 and be fine with it. YOu rbest bet is ofc to send it in to Tamron with your body for calibration....

[grzegorz1987]

Please will someone confirm whether this can be used with zoom lenses? If I was to do this manually, I would adjust the value for the wide and tele ends of the lens, but this process only runs once at one focal length and sets both values.


Eos 5D Mark II - My Lens  EF 50, EF 17-40, EF 24-105, EF 100-400, Extender 2x,
On running this with my EF 10-400 this gives me:

When run at 100   : Both values are set to 0
When run at 400 : Both values are set to 12

How should I calibrate for both ends of this lens? Should I run it at each end, then input the values manually?

[stiefel40k]

Hi,

I'm very new here, so I don't know if I post this in the right place. So I was trying to build ML for 600D because I intend to write an encrypion module with chacha, however as I was trying to build the project, to see if everything is fine I encountered numerous errors with the compiler and co. After fixing everything only one error resides and it is that I can't build the dot_tune module. The compiler error looks like this:

Code: [Select]

Building module dot_tune...
Updated HGVERSION
[ README   ]   module_strings.h
[ CC       ]   dot_tune.o
[ HGDIFF   ]   hgdiff.tmp
[ MODULE   ]   dot_tune.mo
[ STRIP    ]   dot_tune.mo
[ OBJCOPY  ]   dot_tune.mo
[ RM       ]   hgdiff.tmp
[ EXPORTS  ]   dot_tune.sym
[ DEPENDS  ]   dot_tune.dep
Will NOT load on:
    600D (get_config_afma_wide_tele, get_afma_mode, set_afma_mode, and 3 others)
Not checked (compile ML for these cameras first):
    1100D, 500D, 50D, 550D, 5D2, 5D3.113, 5D3.123, 60D, 650D, 6D, 700D, 7D, EOSM
make[4]: *** [../../modules/Makefile.modules:79: dot_tune.dep] Error 1

********************************************************
WARNING: module dot_tune failed to build, deleting
********************************************************
I tried to build ML e.g for 500D as the output suggests, but no help. I tried to understand what is happening in the Makefile.modules, but I had no luck
Regarding this I would have two questions:

• Concidering everything else is fine, and no clusterfuck happens, will my camera break if I use a build where the dot_tune module is not there? Because I don't really need dot_tune during the implementation of the encryption.
• Does anybody have an idea where the problem might be or what I could check?

Thanks for the help in advance!

[a1ex]

That's how the build process checks the compatibility between some module and the camera model. In particular, this module requires the camera to be able to change AFMA.

Those models that don't have this functionality won't have symbols such as get/set_afma_mode, so they won't be able to load this module. The message also tells what functions you need to implement for your module to load on a particular camera model.

You may cross-check your compilation log with the one from nightly builds (see Build log).

[stiefel40k]

That's how the build process checks the compatibility between some module and the camera model. In particular, this module requires the camera to be able to change AFMA.

Those models that don't have this functionality won't have symbols such as get/set_afma_mode, so they won't be able to load this module. The message also tells what functions you need to implement for your module to load on a particular camera model.

You may cross-check your compilation log with the one from nightly builds (see Build log).

Thank you very much alex for you quick answer!

[quimic]

Hi,
I am new to this, and I don't know what I am doing wrong, but it looks like during the automated fine tune process the lens manages to focus every time (I can see the focus confirmation), from -100 to 100. I tried with two different lenses, with the same result. I used a f/1.8 lens to have a shallow depth of field, but it made no difference.
I am using a 7D. I wonder if anyone is experiencing the same thing…

[pulsar124]

I just spent some time trying to make it work on my new camera (Canon 6D) with my new lens (Tamron 24-70 f2.8 VC). Two points:

 - I couldn't make it work (the camera would continue beeping on all the points tried - no bad points at all), until I followed the advice I found online: to switch the camera (using Canon's menu) to "All lenses by same amount" option, in the AF microadjustment menu option.
 - Despite the almost perfect setup, the dot-tune method produced very inconsistent, and mostly wrong results, in particular for the tele-end (70mm) of the lens. My setup: high quality target printed on a large piece of paper (12x18"); direct sunlight on the target; 5m distance from the target; initial focusing done using a remote control (smartphone connected to the camera via USB cable or WiFi), to prevent camera shaking when focusing; sturdy tripod for the camera; multiple tries (refocusing every time). I was getting MFA mostly around -2 ... -5, and around -8 for the wide end (24 mm). When testing these values directly, by taking shots of the target I discovered that the -3...-4 value for the tele-end were consistently producing images which were obviously less sharp than contrast detection shots. When I switched to constant MFA=-7, both tele and wide end shots became as sharp as contrast detection shots.

I've been using dot-tune for years, but unfortunately it looks like dot-tune results should be taken with a grain of salt. I will be re-testing my other lenses, as I don't have confidence in dot-tune results anymore.

[shinoda]

I don't understand how to use this on a 17-50mm : which setting do i have to use and Canon AF and Dottune ?

As Pulsar said, when I set "This lense : wide" or "tele" (and the Canon settings to "This lense") it just continues beeping. I have to use "All lense" on Canon and ML menus for dottune to work. But will it register different AF settings if needed for both wide and tele end ?

Why is there this setting (wide / tele) if it isn't working at all for zoom lenses...

[ArcziPL]

Hi Shinoda, let dot tune run at wide end with "all lenses" setting. After it's done, note down the result. Change lens position to tele, run dot tune again with "all lenses" setting. After it's done, note down the result. Then change mode to " per lens adjustment" and set manually the noted values, separately for wide and tele. It's still not adapted to do it automatically for all cameras, but anyway useful.

BTW, which camera model do you have? I need this workaround for 70D.

[shinoda]

This is indeed for the 70D, thank you for your help, I'm gonna try this right now!

[c_joerg]

I tried to run dot_tune on my 6D with EF 50mm f1.8 STM. I used different targets in around 2m distance.   
I used 4 passes and AFMA mode ‘This lens, prime/both’. I also used all Scan types.

I always get a really constant score graph and result is always 0. I never seen a score graph like in Reply #14. How can it be?
How important is the light source?

[c_joerg]

I have done some more tests with an EF 24mm f2.8 IS USM. Also, I have done this test with different targets and lighting situation. However, I could not test in daylight yet. No matter what range I set, it always comes out a very flat constant score graph. What does that mean?

With the 24mm I sometimes get the value -2 at -100 +100, which cannot be confirmed in a 40 or 20 range.

Is it actually possible for you to freeze the results at the end? Or make a snapshot on the end?
Especially if you scan in automatic mode it takes a long time. It would be nice if the results were longer in the end.

[a1ex]

Is ML able to change the AFMA value on these lenses? In other words:
- if you change the value manually from ML menu, is the change visible in Canon menu?
- if you change it from Canon menu, is the change visible in ML menu?

If any of these is not working, can you try to change the AFMA value from both Canon menu and ML menu, while logging the MPU communication with this build? This log should allow me to reproduce the issue in the emulator. A log covering some part of the AFMA scan process would also help. It doesn't have to be complete; MPU logging is stopped automatically after 20 seconds.

[c_joerg]

I just checked the 50mm

- if you change the value manually from ML menu, is the change visible in Canon menu?

Yes

- if you change it from Canon menu, is the change visible in ML menu?

Yes

Should I still use the logging? 20s is not much to start the dot_tune...



I only started with the tests because the focus on the viewfinder varies a lot from shot to shot depending on the target and the light ...

[a1ex]

Any luck performing the DotTune procedure manually, as explained by the author (horshack) ?

For example, if you hold the camera still, focused on the chart, and you change the AFMA value to some extreme values (say +/- 100 or whatever the menu allows), do you still get focus confirmation? After some threshold, you should no longer get the confirmation.

Maybe the focus chart is "too sharp" and you still get AF "confirmation" even if the image is somewhat out of focus? Just a guess; back then, I've only tested on regular subjects (i.e. something with fine print or other sharp details, but not on a dedicated focus chart). I did not test on 6D, but other users reported success.

Otherwise, I'm out of ideas. You could try looking at previous posts for suggestions, but I guess you already did that.

I'd still like the logs, if possible. It won't cover the entire dot_tune process, but as long as it catches a few AFMA value changes, it's fine. Manual adjustments from both Canon and ML menus should be covered, too (just scroll through a few values, nothing fancy).

[ArcziPL]

I assume it might be a bug in DotTune, which I experienced on 70D.

Workaround: change the DotTune to use ~"same settings for all lenses" instead of separate setting for each lens. Then run it, it should deliver the right result. Note it down, change mode to per lens correction and dial in the values manually. I was shortly looking at the source some time ago in order to fix it but didn't have enough time to really manage it... It just seems the DotTune always changes the value ~"same settings for all lenses", ignoring the mode selection during the scan, so the value it's setting during the scan has actually no effect, when a different mode is chosen.

[c_joerg]

I'd still like the logs, if possible.

Can I upload the log directly?
https://drive.google.com/open?id=1rqfUPcqdmjB7iuPuFNBYeOXLKz8rAvPF

For example, if you hold the camera still, focused on the chart, and you change the AFMA value to some extreme values (say +/- 100 or whatever the menu allows), do you still get focus confirmation? After some threshold, you should no longer get the confirmation.

That’s works very well. Max range in the Canon Menu is 20.

Maybe the focus chart is "too sharp" and you still get AF "confirmation" even if the image is somewhat out of focus?

As can be seen from Reply # 267, I use different charts. The different charts and lighting have a big impact on the variance of the viewfinder focus. Here are my previous experiences:
A Siemensstar in artificial light is the worst case. Here the focus has the most varianz. It gets a bit better in sunlight. Horizontal and vertical lines have less variance. Horizontal lines work best, presumably because only one component of the cross sensor is used.

Here you can see how the setup is at the Canon service for the adjustment:
https://www.dslr-forum.de/showpost.php?p=15313563&postcount=40

I assume it might be a bug in DotTune, which I experienced on 70D.

It looks quite like this…

Workaround: change the DotTune to use ~"same settings for all lenses" instead of separate setting for each lens.

This works very well even in the 20 range . Thanks for the hint.
Is it correct that every time I start the camera, the scan range is set to Auto?

[c_joerg]

To see the impact of the of different charts, I attached two score charts. The upper diagram comes from the Siemensstar, the lower one comes from the target proposed by the DotTune method.