Shaking image and whirring sound - Calibration error

[Bernhard Guggenberger]

Hello,

we did a first test with OpenCap today. We had a pool of overall 3 Iphones and started with a two camera setup. The first calibration and acquisition of some trials worked fine.
Later on we wanted to change the setup. While starting the calibration of the second setup, one of the Iphones behaved strange. The image started to "shake" (it looked a bit like motion blur) and it made a whirring sound. We restarted the calibration, but the same thing happened. Further, we changed the malfunctioning phone with our third spare device, but the same thing happened. While all those trials, the second phone worked well.

Error_Iphone.JPG (46.25 KiB) Viewed 1054 times

Have you ever experienced something like that? Do you have any suggestions, what to change in the setup?

Here the specification of the malfunctioning devices:
iPhone 1 (First test worked, Error at second calibration)
Nice Name: iPhone 11
Machine Model: iPhone12,1
Family name: A2221
EMC number: 3304
CPU speed: 2.66GHz
Screen size: 6.1 inch
Screen resolution: 1792x828 pixels
Production year : 2019
Production week : 42 (October)
Model introduced: 2019
Capacity: 128GB
Memory - maximum total: 4GB
Factory: DN (China, Chengdu - Foxconn)


iPhone 2 (error at first calibration attend)
Nice Name: iPhone XR (Global/A2105)
Machine Model: iPhone11,8
Family name: A2105
Model Number: MRY92
Group2: XR
CPU speed: 2.49GHz
Screen size: 6.1 inch
Screen resolution: 1792x828 pixels
Production year : 2018
Production week : 45 (November)
Model introduced: 2018
Capacity: 128GB
Memory - maximum total: 3GB
Factory: C8 (China)

Sincerly,
Bernhard

[Antoine Falisse]

Hi Bernhard,

Thanks for sharing. We have experienced this a few times with an iPhone 11. It is not clear to us what is happening, we suspect a hardware problem but we are not sure. Is it consistently happening for you (like at each attempt)?

Thanks,
Antoine

[Bernhard Guggenberger]

Hi Antoine,

thank you for your fast response.
Firstly, it worked well with the two camera setup. After about 6 trials the error occured on one phone for the first time.
As we also wanted to test some other camera position settings, we decided to rearrange and recalibrate the setup. We tried to calibrate the setup for three times (inbetween we restarted the app and reconnected the phone to the web application), but we got the same error each time on the same phone (the other phone worked normally). We then decided to change the malfunctioning phone with our third spare device, but we got the same error on it.
Unfortunately, we ran out of time, so we could not test wheter a restart of the phone or changing the lighting in the room would fix the problem.

Did restarting the device solve the problem in your case?

Thanks,
Bernhard

[Antoine Falisse]

This problem occurs very sporadically for us, that's why we have not been able to get to the bottom of it so far. Usually killing the app and starting a new session works.

[Emma Hertel]

Has there been found any solution for this problem yet? I have this exact issue when using iPhone 11 and iPhone 11 Pro. The error happens immediately during the first calibration and has occurred on three different iPhone 11's and one iPhone 11 Pro. It does not work to kill the session and restart. The setup works perfectly with iPhone XS and iPhone 14.

Many thanks,
Emma

[Scott Uhlrich]

No solution. Iphone 11 is the only phone it has seemed to happen on. We typically just try different phones.