Calibration fails on Mark II- what are best practices for calibration??

I can’t get my Mark II to calibrate. I can get it up and running on my iPad Pro 12.9 and get it to start to take pictures to calibrate, see all the dots and the color and IR picture, but after taking 10 or so pics it throws an error message, talks about making sure the mount is correctly aligned and starts to take another pic or two, but then crashes.

-What are the best scenes to calibrate on? Lots of lines? Fairly big, bold objects or are smaller details good (repeating like a grate or pattern, or random like foliage?)
-Is it best to circle one object and take multiple pics from slightly different angles, or move around and take pics with little overlap?
-How ‘off’ can the mount be and let calibration still work? I think I have it pretty much in the right spot, but the error message implies that I don’t?

I’m into 3D printing and I’m a materials guy, not a software/hardware guy. I got this two weeks ago, spent the morning trying to get it to work and put everything into a box and haven’t gotten back to it. I have to say that I’m pretty disappointed for the amount of money spent.


Me too facing same issue spent weeks trying

Contact Occipital. They sent me a link to differentiated version of Calibrate for 1st gen 12.9 iPad Pros. I haven’t tested it yet, but at least they are addressing it.

Same boat, been over a month and still have better luck with the first gen sensor and 3rd party apps. I’m holding out hoping something changes and we can use the new tech.

me too been waiting and they send a few step all can’t work, very stressful as i help a few of my student purchase too… it’s like having the device and can’t use! really spoil my name

Calibrator app still not working with new firmware update. Sporadic calibration success possible but most of the time it fails. Should we use the app store version or get a special version still to succeed?


I have a problem with my mk2 sensor,

First part of the calibration with wide lens goes with no issues (that checkerboard paper) but the second part is saying that I check if my bracket is aligned to the camera.

My camera is pretty close to the sensor (in line)

Within maybe 5mm.

Is my alignment problem or is it the software?


Thanks guys for the responses. I’m running the ‘special’ app version for the iPad Pros. I got it to calibrate once, but the scanning was horrible- just didn’t work. Then it crashed. I need to dedicate a couple of hours to it this weekend before I ask for a return. This was a lot of money to have it not work at all. I’m willing to be patient, but not forever.

What ever works right in 3D printing??? :wink: . Luckily I have two Printrbots, so I’m used to endless tinkering…

Hello everyone!

I apologize for the radio silence regarding Calibrator! The truth is, everything has been a top-priority issue, which means that some top-priority issues have had to be put off for other priorities. Specifically, the most pressing issue was pushing an updated SDK version with accompanying firmware version to fix connectivity and stability issues.

I’m happy to say that we have released a new version of Calibrator that should fix most, if not all, of the issues people have been seeing. Among these issues:

  • Updated extrinsic translations that made it impossible to advance past bracket calibration (blue dots), including for Bridge cases and the 12.9-inch first gen iPad.
  • Fixed issue where the camera would fail to initialize again after bracket calibration (on the refinement stage) and users would only see a black screen.
  • Fixed issue where the camera permissions notification would cause the app to crash.
  • Fixed issue where the app alerted user that the sensor’s battery was depleted, even though the sensor still held 60-75% charge
  • Fixed issue where the calibration would not actually be stored in the sensor.
  • Added a pop up to alert users to update their firmware if they are running 0.98.

In general, this is a much more stable and better version of Calibrator.

Known Issues

  • It seems the extrinsic translations for the 9.7-inch iPad Pro with regards to Mark II are still off.

Regarding Calibrator best practices, we recommend taking a look at this video:

If you live in an area with little sunlight, you can use the below calibration target for indoor calibration.

indoorCalibrationTarget-compressed.pdf (336.0 KB)

So, for everyone, even people with the older 12.9 Ipad Pros, we should download the new app from the App Store? Do we need new firmware for the Structure? ( I have no idea how to update that?).


Yes, you should delete the temporary OTA we sent out and switch to the App Store version.

To update firmware, please download Structure app here (, tap the “i” icon in the upper right, and tap Update Firmware.

Be aware, if you stream too long in the Structure app, the sensor runs out of memory, and you will not be able to complete the update process. Please also make sure to run the update process with at least 50% battery remaining.

The unit keeps thinking the wide angle lens is on when it isn’t.

The calibration for when I do have the wide angle lens on just goes and ‘calibrates’ even when there is no lens attached.

I can ‘calibrate’ the normal lens but it only works from about 4 feet away on anything.

Are you seriously supposed to use the print of the Pollock painting printed on 8x10 paper?

The apps randomly die or go to black screen.

The ipad loses connection with the camera.

The ipad BURNS through battery at about 1% a minute.

At one point the image in Scanner starts to go overexposed and eventually goes almost all white.

Yea, I’m pretty much done with this. I want to know what your return policy is. This works no better than the old versions. I’ve been patient and was excited about the new revisions. It just doesn’t work.

I’ll try to calibrate it outside tomorrow.


Impossible de calibrer mon mk2 sur iPad Pro (2018) 12, 9 pouces avec “Wide Vision Lens”

  1. calibration avec Checkerboard fonctionne très mal, je n’arrive pas à capturer la grille comme il faut dans certaines positions.
  2. calibration au soleil ne fonctionne pas, l’application reste bloquée.
  3. calibration à l’intérieur d’une pièce ne semble pas non plus fonctionner, j’ai essayé au moins pendant 10 minutes mais je ne suis pas arrivé au bout de la procédure. J’ai constaté que les petits points bleu qui apparaissent semblent êtres positionnés n’importe comment.

En conclusion, je n’ai toujours pas pu employer le mk2 que j’ai acheté il y a plusieurs mois maintenant!
J’avais le premier strucure sensor avec lequel je n’avais pas eu de problèmes!
J’attends de vos nouvelles car je dois utiliser le mk2 pendant mes vacances avec canvas pour scanner un châlet. Si je n’arrive pas à le faire fonctionner, j’envisagerai sérieusement de vous demander de me rembourser