HELP wanted! (Dropbox link in the text)

[Mr.Vain]

Hi!
In the dropbox link below i have a project wich is from a phantom 4 and the first chunks was no problem but suddenly everything gets FU when i try to  use my gcp. The pointcloud goes twisted and the fault is a couple of hundred meters and i cant understand what i am doing wrong this time. If i have the photos checked and import my gcp they are placed correct but when i stat to place them everything goes bananas. Can anyone download the project and try do get it right and tell what i am doing wrong? This is from a regular phanthom 4 and i also have a P4 RTK and with that one is never any problems at all.

Thanks in advanced.

https://www.dropbox.com/sh/67zxg1fo455jl73/AABxv3FXyVAv6X_Mc4ZY27xUa?dl=0

[Paulo]

Mr. Vain,

it seems the images can be correctly aligned but when I introduce 3 CPs in adjustment, there seems to be big errors in east and north of these as seen in errors in attached screen copy....

Note that original image's altitud has to be modified from around 410 m to around 90 m to fit with ground... this is issue with Phantom drones....

Maybe this helps,

[Alexey Pasumansky]

I agree with Paul, the altitude information in the last chunk seems to be incorrect.

You may need to subtract 318 meters from the altitude values of the cameras in the third chunk and Update the reference.

[Mr.Vain]

Thanks guys!! That was the problem. After fixing that it worked like a charm.

[Mr.Vain]

I agree with Paul, the altitude information in the last chunk seems to be incorrect.

You may need to subtract 318 meters from the altitude values of the cameras in the third chunk and Update the reference.

Why 318m, how do i know that is 318m?

[Alexey Pasumansky]

Hello Mr.Vain,

Flight height above the ground is about 95 meters, markers altitude is about 20 meters, so cameras should be on 115 meters level, whereas they are on 433 meters.

So 433 - 115 = 318 difference that should be corrected.