I was recently asked how I managed to change the altitude to QFE (ground level) on my videos, well when I can be bothered to do it! So here is how to do it.
I use Dashware to add the tapes to the video before editing the video, I do this before to ensure the data is in sync with the video.
I capture the video using my TomTom Bandit, which has a built in GPS. However like all action cameras I know of, it suffers from strobing on the prop. To overcome the strobing I made an ND8 (neutral density) filter by ordering a plastic ND8 filter from ebay. I cut in a circle and held in place using some large heat shrink. Anyway that’s for another day today we are looking at how to offset the reported altitude. Or put another way QNH to QFE.
For this I will assume you have your data and video file ready and that you know how far out the altitude is.
Below I’m using Dashware version 1.9.1
Load your video in the normal way then:
1. Open the load data screen
2. Select the data file and click “Edit Profiles”
3. Make a clone of the data profile you are using, so that you can edit it.
4. Add a Math Calculator (bottom left area) that takes the Altitude and subtracts the offset needed, you may need to play a little with this value. the value is entered into the “Constant Parameter”. use the other settings as shown below.
5. Call this new channel QFE in the output value.
6. Now add a mapping channel for QFE by clicking the + in column mappings
7. Map the columns as shown below
8. Click OK to close the Data Profile Editor screen
9. Then back at the add data file screen ensure you have the newly create Clone profile selected and click add to show your new altitude.
I hope this helps!