Altitude vs Overlap

[Bob Coughlan]

Hi all

New to the forum. I’m an EVO I owner, based in Johannesburg, South Africa.

I’ve asked this question on Autel’s website, and on Autel’s YouTube channel, but received no response (quite disappointing, to be honest). Maybe it’s been asked before on the forum in a different manner but I could not find it in a search.

Regarding overlap settings, surely the higher the altitude, the greater the overlap (factoring in camera angle and some basic trigonometry). My thinking is that the higher the altitude, the bigger the piece of land covered by the photo (assuming my gimbal is pointed directly downward). Or is there something I’m not considering?

Anyway, I notice that when setting up, for example, a polygon mission, when I change the altitude, the distance between the opposing legs of the flight does not change in the way I currently think it should.

Ive just started learning to use WebODM and have been getting good results but would like to be able to plan my flights more efficiently by only taking the amount of photos I really need to take.

I’ve made a spreadsheet to assist with calculating the required distance between the opposing legs of my missions to achieve both 65% and 85% overlap, and it seems to be giving me the right values to use, but then I still have to kind of ‘eyeball’ it on google maps (by measuring out the required distance on the map) then adjusting overlap in Autel Explorer until the distance between the opposing legs of the mission looks about the same as the distance I measured on google maps, based on my altitude and the overlap distance I calculated in my spreadsheet.

Anyway, it would really be nice if Autel Explorer Mission Planner could be of more assistance in automating this process. Does anyone know if the overlap setting in Autel Explorer Mission Planner is based on an assumed altitude? And if so, what is that altitude?

Thanks for any feedback.

Bob Coughlan

 

[Ansia]

It is to my understanding they consider a 70% overlap, regarless of height

 

[Bob Coughlan]

It is to my understanding they consider a 70% overlap, regarless of height

I see that it defaults to 70% when first setting up the mission, but if one adjusts the altitude (while the overlap setting remains unchanged), it’s reasonable to conclude that we should expect to see a change in the distance between the opposing legs of the mission path.

My question relates to the fact that currently, the only way to increase or decrease the distance between the opposing legs of the mission is by adjusting the overlap setting.

Both variables (altitude AND overlap) should have an effect upon the distance between the opposing legs of the mission, but they don’t.

Thanks

Bob

 

[Ansia]

Remember to set your photos to 4:3. Using 16:9 will ruing the end results.

 

[Hawaii Drone Imaging]

@Bob Coughlan , true regardless of altitude, you still want 70%. It is more beneficial to capture images at a higher altitude and get full use of your sensor range or field of view. If you're at 50ft, sitll 70% overlap but small area covered. 200ft, still 70%, but you will have more area covered. I used to use Dronedeploy when I had a DJI aircraft. Here's a little info they shared with my 3rd party software I was using. Hope it helps. Speed makes a big difference also.

Making Successful Maps

Know what habits contribute towards becoming a mapping pro!

support.dronedeploy.com

 

[Bob Coughlan]

@Bob Coughlan , true regardless of altitude, you still want 70%. It is more beneficial to capture images at a higher altitude and get full use of your sensor range or field of view. If you're at 50ft, sitll 70% overlap but small area covered. 200ft, still 70%, but you will have more area covered. I used to use Dronedeploy when I had a DJI aircraft. Here's a little info they shared with my 3rd party software I was using. Hope it helps. Speed makes a big difference also.

Making Successful Maps

Know what habits contribute towards becoming a mapping pro!

support.dronedeploy.com

Thanks for the helpful advice, and the link

It appears you’ve confirmed my suspicion that Autel Explorer’s Mission Planner is not working as it should, because if I increase mission altitude, but keep the same overlap setting, I should see an increase in the distance between the opposing legs of the flight, with fewer waypoints and a shorter total flight distance, but the waypoints and total flight distance remain exactly the same.

It’s only when I make changes to overlap that the amount of waypoints and total flight distance changes.

Something is not quite right

Thanks again

 

[Bob Coughlan]

I just realized that the Mission Planner for EVO II does exactly what I’d expect it to do for EVO I, i.e. it spreads out the opposing paths of the mission if the altitude is set higher, but it appears the EVO I Mission Planner has not yet caught up

Maybe some EVO II users have read my post and thought I’m mistaken

I do hope that EVO I’s Mission Planner is updated in the near future

Thanks for all the feedback anyway

 

[Bob Coughlan]

Hi all

New to the forum. I’m an EVO I owner, based in Johannesburg, South Africa.

I’ve asked this question on Autel’s website, and on Autel’s YouTube channel, but received no response (quite disappointing, to be honest). Maybe it’s been asked before on the forum in a different manner but I could not find it in a search.

Regarding overlap settings, surely the higher the altitude, the greater the overlap (factoring in camera angle and some basic trigonometry). My thinking is that the higher the altitude, the bigger the piece of land covered by the photo (assuming my gimbal is pointed directly downward). Or is there something I’m not considering?

Anyway, I notice that when setting up, for example, a polygon mission, when I change the altitude, the distance between the opposing legs of the flight does not change in the way I currently think it should.

Ive just started learning to use WebODM and have been getting good results but would like to be able to plan my flights more efficiently by only taking the amount of photos I really need to take.

I’ve made a spreadsheet to assist with calculating the required distance between the opposing legs of my missions to achieve both 65% and 85% overlap, and it seems to be giving me the right values to use, but then I still have to kind of ‘eyeball’ it on google maps (by measuring out the required distance on the map) then adjusting overlap in Autel Explorer until the distance between the opposing legs of the mission looks about the same as the distance I measured on google maps, based on my altitude and the overlap distance I calculated in my spreadsheet.

Anyway, it would really be nice if Autel Explorer Mission Planner could be of more assistance in automating this process. Does anyone know if the overlap setting in Autel Explorer Mission Planner is based on an assumed altitude? And if so, what is that altitude?

Thanks for any feedback.

Bob Coughlan

Autel just replied to me on one of their latest YouTube videos

I raised the same issue about altitude vs overlap on the EVO 1 and they stated that they’re working on an update for EVO 1.

At least there’s been a response, which I appreciate, and that gives me some hope.