I missed this post, patch is working, Thanks!  Also checked 7.0.26 and it seems fixed out of the box, but it's a bit too buggy still to use.

Hello dpizzle,

We have uploaded a patch for the iPhone 8+. It will be applied after performing the following:

1. Make sure that the device's Wifi is enabled and can connect to the Internet
2. Uninstall your test app with Vuforia integrated
3. Reinstall the same test app
4. Start the same test app and let it run in idle state for 30 seconds
5. Stop the same test app
6. Restart the same test app

This patch is only valid for Vuforia 6.5. Note that this update will only persist for as long as that version of the test app is installed on that device. Reinstallation of the app on the device *may* over-write the patch. If so, you'll then need to redo the provided steps above.

Upon startup the SDK will attempt to download the patch and apply it before Vuforia camera start. Whether or not this operation completes before first camera start depends entirely on upon app experience, network connectivity and network latency.

This is only for the iPhone 8+ currently, I will let you know the status of the iPhone 7+.

Thanks,

-Vuforia Support

Thank you so much,  here's some steps to reproduce if it helps.  It's easiest to see on the sample VuMarks, it's there on the sample Image targets, but harder to see (it's more prevalent on some custom image targets more than others, but I couldn't figure out why).

1. Print a sample VuMark

2. Load VuMark sample in either Unity or native Xcode (problem exists on both).  Then place 3d object on VuMark so you can see the jitter.

3. Launch app and place iPhone in a stand about 30 degrees tilted down in front of VuMark.

Let me know if you need any more info.

Hello dpizzle,

We are looking into your report and I will post here with any news I have to share.

Thanks,

-Vuforia Support

More video showing it, this time on VuMarks: http://relativedistance.com/VuforiaTest2.mp4

It doesnt seem to affect the front facing camera.  Did something change internally from these two iPhones, maybe Vuforia is sampling a higher resolution which is making it more sensitive?

I couldn't figure out how to turn off image stabiization with a native plugin, if it's even on, not sure.  

Can we get a confirmation that this is on your radar as an issue?

After more research, my gut says:

This is also present on the iPhone 7+ given the camera similarities

and

It has something to do with Optical Image Stabilization (OIS), Focus Pixels,  or Cinematic Video Stabilization

I guess it's time to write a native plugin to change these settings (which I hope is possible).  I'll report back here If i can solve it.

Would love to get a few words from an engineer on it, if someone had the time.

 

Did some more testing.  The discrepancy between the two devices tracking quality also exists in Unity 5.6/ Vuforia 6.2.10.

It has nothing to do with focus mode. I tried them all.  Also, the jitter issue was the same no matter how in focus or out of focus the image target was, which I find very odd.    

Again the iPhone 6s+ is rock solid and flawless tracking no matter what, not so with the iPhone 8+.

BTW, target is 5 stars.