# Vertical shift
**URL:** https://community.pix4d.com/t/vertical-shift/5698
**Category:** PIX4Dmapper Questions/Troubleshooting
**Created:** [October 29, 2016, 6:00pm UTC](https://community.pix4d.com/t/vertical-shift/5698 "2016-10-29T18:00:05Z")
**Posts on this page:** 3
**Page:** 1
### Author:  [@Matthew\_Joyce](https://community.pix4d.com/u/Matthew_Joyce)
#### Post date: [October 29, 2016, 6:00pm UTC](https://community.pix4d.com/t/vertical-shift/5698/1 "2016-10-29T18:00:05Z")
I have data from Wednesday I am processing. I used 8 GCPs, set with RTK GPS, tolerance \<0.1 foot; no geotagging of the images. All points are correct, but the computed point cloud is +11-12’ above the correct surface. What am I missing?
Re-processing steps 1 and 2 is a time-consuming affair, but clearly I’ve got an error in my setup. All GCPs are recognized with a precision of 0.02m, and yet all are computed 3m, some almost 4m, above.
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### Author:  [@Matthew\_Joyce](https://community.pix4d.com/u/Matthew_Joyce)
#### Post date: [October 29, 2016, 6:13pm UTC](https://community.pix4d.com/t/vertical-shift/5698/2 "2016-10-29T18:13:29Z")
Just saw my project was built in metric… my GCP elevations are in ft… Ouch.
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### Author:  [@Clarence\_Ndunguru](https://community.pix4d.com/u/Clarence_Ndunguru)
#### Post date: [November 6, 2016, 12:59pm UTC](https://community.pix4d.com/t/vertical-shift/5698/3 "2016-11-06T12:59:33Z")
Good catch!