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(from the adding more words makes stuff better department)

Vacation time is here again, and with that comes the gathering of the cameras and cleansing of the lenses. It was also time to calibrate the lens/body combinations by adjusting the Auto-Focus Micro-Adjustment settings. There's loads of products on the market that can help with that, but none that I know of that run on an Android.

I've discussed that possibility with Reikan Focal's author when that product was still new, but nothing ever came of it. So what else could I do than build something myself ?

The result is DSLR Controller AFMA. (If you can come up with a better name that isn't used by fifty other software packages, I'm all ears). A portable AFMA calibration tool based on the moiré method ( See: http://www.komar.org/faq/camera/auto-focus-test/ ).

The app can control the camera to shoot at a target and calculate an AFMA value to set. That target can be a different Android device running the app and playing the target, or any other device able to run a web browser and navigate to the Android's built-in webserver (iPad, laptop, TV, etc). Heck, if your USB cable is long enough or you connect to your camera via Wi-Fi, the same device that controls the camera can show the target.

For the moiré method to work, it is important that the target is pixel-perfect on the device displaying it. Even if you can't connect your camera to the Android device, you can still perform the tests manually with this app providing the target for it, either on it's own screen or through its web-server.

I did grossly underestimate the time I would be spending on this little project, and as a result it's still bare and basic and my time is up. (In fact, time I had allotted to other projects like 500 Firepaper and Pry-Fi got swallowed as well, ouch!). Note that this isn't meant to be a competitor to extensive tools like Focal - this is just quick, rather dirty, and portable.

But, it does work. I've used it to calibrate about a dozen lenses, and those calibrations appear to be good, so I'm ready to go abroad.

You can get the app from Google Play by clicking the link in the box below.

You can find the manual here: http://dslrcontroller.com/afma/ . Reading the manual is a must for usage, by the way. You will mess up if you don't.

The XDA thread for discussion can be found here: http://forum.xda-developers.com/showthread.php?t=2662743

This is a very niche thing, I'd actually be really surprised if more than a few thousand people end up finding it useful...