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Flying altitude and image quality when surveying with DroneDeploy

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Hi everyone!
First of all Happy New Year!!!

I have a question about flying altitud when surveying for maps. The support on DroneDeploy's web explains that in order to have a better quality map you have to fly higher in order to get more area per shot, that will translate in a better stitching process. Now here is the thing, if i fly higher i will also get les pixels per square meter, which translates in lower image quality..

So, for the same aircraft and camera, flying higher gives you more surface per shot with less image quality and flying lower does the oposite, les area per shot with more image quality. I guess the question would be, am i missing something and my thinking it's wrong? is there an altitud where these two parameters get balanced and you get a great quality map without sacrificing image quality??

My objective is to get an orthomosaic of great quality, but without loosing the ability to zoom in and still have a good image!

Of course that there are flight time and battery repercussions as well, but let's asume that's not a counsern for this case, i'm interested only in the quality right now.

In case you're wondering, i'm using an inspire 1 with an X5 camera and DroneDeploy to map.

Thanks for your thoughts!!
 
I found DroneDeploy (and the other online services) to be too restrictive in their ability to allow different GSD values with different lenses, and although ideal for simple style orthos and 3D meshes, where you need to tweak to maybe get a hi-res version, they're not really suited. Whether this is because offering the user too much choice creates a bottleneck on their processing servers or not i dont know.

For me Id always use software the processes in-house - clients much prefer the security of knowing their data isn't on the cloud - it does mean a beefy computer however.
 
I found DroneDeploy (and the other online services) to be too restrictive in their ability to allow different GSD values with different lenses, and although ideal for simple style orthos and 3D meshes, where you need to tweak to maybe get a hi-res version, they're not really suited. Whether this is because offering the user too much choice creates a bottleneck on their processing servers or not i dont know.

For me Id always use software the processes in-house - clients much prefer the security of knowing their data isn't on the cloud - it does mean a beefy computer however.

I was thinking on doing the same. Wich software do you use to process the images?

Donyou prefer to fly for better camera coverage or low for better image quality??


Sent from my iPhone using InspirePilots
 
I was thinking on doing the same. Wich software do you use to process the images?

Donyou prefer to fly for better camera coverage or low for better image quality??


Sent from my iPhone using InspirePilots
Look at Correlator3D UAV and Pix4D. The survey firm we regularly use recommended Correlator3D. We have performed a trial run (30 days free for each) and prefer the additional reporting capabilities of Correlator3D. Both allow much more control in-house over Drone Deploy, although I still use the Drone Deploy app for flight planning.
You will need to contact both companies for pricing and decide which works for you. For a business solution, you can probably count on the bottom end to run around $3500US for a year up, depending on what version you choose.

In closing, set a minimum of five GSPs; the four corners of the site and the center or thereabout. Makes it very easy to rectify your orthomosaic and drop it into an existing rectified image file.
 
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I use DroneDeploy and have had really good results. I have a client that wants high resolution ag maps. I also fly with an Inspire 1 and X5. After a few dozen flights, I have found my best results (stitching & resolution) come from 250ft. And 80% overlap. I've spoken with Mike, the CEO of DroneDeploy and he assured me that new features and capabilities will be offered soon. They recently released the ability to modify flight speed, I haven't had the chance to use it yet though. Feel free to PM if you have questions about the software.


Sent from my iPhone using InspirePilots
 
They recently released the ability to modify flight speed, I haven't had the chance to use it yet though.
ooo, how? I have been wanting that but the only way I can seem to slow it down is to reduce the altitude. Might just be being dumb...
 
06a7e35ba21a5a08657151bd8490ab58.jpg


I just bought new props and it came with a little quick start guide that it says the propellers have a lifespan of about 500 flights. With an average of 15 minutes a flight, that gives you 125 hours.. which sounds like a lot!! What do you think?
 
06a7e35ba21a5a08657151bd8490ab58.jpg


I just bought new props and it came with a little quick start guide that it says the propellers have a lifespan of about 500 flights. With an average of 15 minutes a flight, that gives you 125 hours.. which sounds like a lot!! What do you think?

I think that this doesn't have anything to do with mapping or surveying and does not belong here.
 
I found DroneDeploy (and the other online services) to be too restrictive in their ability to allow different GSD values with different lenses, and although ideal for simple style orthos and 3D meshes, where you need to tweak to maybe get a hi-res version, they're not really suited. Whether this is because offering the user too much choice creates a bottleneck on their processing servers or not i dont know.

For me Id always use software the processes in-house - clients much prefer the security of knowing their data isn't on the cloud - it does mean a beefy computer however.
Yt
Look at Correlator3D UAV and Pix4D. The survey firm we regularly use recommended Correlator3D. We have performed a trial run (30 days free for each) and prefer the additional reporting capabilities of Correlator3D. Both allow much more control in-house over Drone Deploy, although I still use the Drone Deploy app for flight planning.
You will need to contact both companies for pricing and decide which works for you. For a business solution, you can probably count on the bottom end to run around $3500US for a year up, depending on what version you choose.

In closing, set a minimum of five GSPs; the four corners of the site and the center or thereabout. Makes it very easy to rectify your orthomosaic and drop it into an existing rectified image file.

Hi RMartin
I have used Correlator and Pix4D along with GCPs 80% overlap at 200 to250 feet and I get inaccuracies when rechecking the distance and location of the GCPs on the finished map of up to 5 inches horizontally and 12 inches virtically. Not as good as I was expecting. Any tips tricks to share on how to improve on the overall accuracy?? We got better results when shipping data off to Bentley or Propellar but these guys start at 8500 a year. We are a 35 man engineering firm with one registered surveyor.
Thank you in advance
 
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Yt


Hi RMartin
I have used Correlator and Pix4D along with GCPs 80% overlap at 200 to250 feet and I get inaccuracies when rechecking the distance and location of the GCPs on the finished map of up to 5 inches horizontally and 12 inches virtically. Not as good as I was expecting. Any tips tricks to share on how to improve on the overall accuracy?? We got better results when shipping data off to Bentley or Propellar but these guys start at 8500 a year. We are a 35 man engineering firm with one registered surveyor.
Thank you in advance
What is the accuracy of the GPS you used to set the GCPs? What area volume are you trying to survey and what number of GCPs are you using?
 
What is the accuracy of the GPS you used to set the GCPs? What area volume are you trying to survey and what number of GCPs are you using?

10 to 80 acre undeveloped land w some buildings on them. Mostly unwooded. GCPs check out within an inch horiz. And 3 inches vert. In cad but on the created ortho. From the flight Not so good. We do at least 5 GCPs per 10 acres or so depending on the shape of the land. I overfly the sites a tad to be sure the GCP are usable on the perimeter. The accuracy is ok for planning municipal parks and playgrounds, sewer and water designs, but not for land developments and subdivisions.
I locate every painted GCP on as many photos as I can see. Usually on at least 5 photos and as many as 10 or so. I know Pix 4D is good. Just a little disappointed.
 
Would you like me to try the dataset with 3d Survey and Photoscan Pro for you ?

I would like that. Aren't these two different photogrammetry softwares?
I can easily send the GCPs. The photos will need Dropbox or something else.
While I'm here.........is there an easy way to produce a good DTM without buildings and trees?
I find the default DTMs to be way too smooth and not very useful. I usually remove buildings and trees in the point cloud editor on the DSM. Very tedious. But it gives us the file format that is usable in Autocadd.
 
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10 to 80 acre undeveloped land w some buildings on them. Mostly unwooded. GCPs check out within an inch horiz. And 3 inches vert. In cad but on the created ortho. From the flight Not so good. We do at least 5 GCPs per 10 acres or so depending on the shape of the land. I overfly the sites a tad to be sure the GCP are usable on the perimeter. The accuracy is ok for planning municipal parks and playgrounds, sewer and water designs, but not for land developments and subdivisions.
I locate every painted GCP on as many photos as I can see. Usually on at least 5 photos and as many as 10 or so. I know Pix 4D is good. Just a little disappointed.

The example below shows a few overlapping jobs that I recently did. 5 GCPs are the minimum for approximately 4-7 acres that we use. That is for a rectangular box; if the flight area is oddly shaped I tend to nail each corner and a few i the middle to firm up everything else. I use a Trimble Geo 7x with mapping grade software installed for centimeter accuracy to set my GCPs. Most of the results I get very from 1/2" to 1" depending upon how accurate I am at identifying the GCPs in Pix4D.
I make sure to have at least one pass of overlap between jobs for larger tracts.

Vertical accuracy is going to be the weak point unless you are using a total station to set control. GPS is not well-known for vertical accuracy. You can always add more control to help firm the numbers up. An EXIF editor is also an option from what I have read but vertical accuracy is not overly important to me; we map, not survey.
 

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