I’m half way through mapping a large area (130 acres) and need to continue the next day. So uploaded all the images captured so far to DD to start processing. Now seem to have lost the function to ‘complete mission’, I can’t see the dotted lines where the drone has captured. How can I carry on where I left off?
Are you using Ground Control Points?
I created the map in the app, not sure if that means I’m using ground control points. I got about 5 flights done (30%) of the map and so started uploading the images. They’re still being processed. Once processed will I be able to continue do you think? Right now under the fly section all I can see is the entire area to be mapped again. Thanks for getting back!
If you are not sure then you are probably not using GCP’s. If you are going to fly this project multiple times you need to use either survey grade points or sub-meter post flight points as described in the thread below. If you have to fly the project in multiple flight then make sure you have GCP’s common between adjacent flights. If you do not do this you will see a shift between flights and the composite maps due to takeoff position changes, atmospheric conditions, lighting and GPS alignments.
Feel free to contact me and we can walk through this. Do you have a fully completed flight processed or is this the first attempt?
Michael, many thanks for your detailed help. Let me absorb this so I can ask as few questions as possible. It would be great to contact you so you can walk me through it. Can I call you over Skype or WhatsApp? (The flight is 30% complete and still processing).
Either of those is fine. I am available until 4:30pm Central US time.
@Rogue1, once you start uploading the pictures, it thinks you’re done with that particular mission and it starts to process. You can’t then add to the partly processed map or continue the half a mission that hasn’t been flown yet. It thinks you’ve flown all you need.
The best you can do in this instance, is to duplicate the map and redefine the extent of the map not yet flown and then add to your other images. The only problem with that, is that unless GCPs are used, you’re relying on the accuracies of the GPS info in the metadata, which is subject to change from day to day, using different satellites etc.
Or if it was me, start again and fly the whole thing from the beginning. It’s not so big it can’t be done.
Good stuff. My thoughts exactly.
Hi James, really appreciate you getting back. I just had a chat with Michael who was super helpful and told me the same thing. As you suggest I’ll put this first attempt down to learning and start a fresh mission tomorrow. I think I was too low also which made the project bigger than necessary. So I should be able to do it all in one go now no problem. Thanks for your input. Alex.
The image finished processing so thought I try downloading that one to see how it came out. It seems to limit the size of the download so with this one I’m not able to get the maximum available size. Is it possible to retrieve the full size image another way?
Unfortunately that may be a restriction of the trial account. This shouldn’t be a problem though being just 1/4 of the 56ha. We fly 200ac maps all day long. @Andrew_Fraser, what do you think?
Happy to upgrade to the Pro account if that solves it. Just wanted to show the client an example before going ahead with the account. Once again, thanks Michael.
Unfortunately, I don’t think this is limited to a Trial account. I suffer from this now. A couple of years ago, I had a long exchange of emails with Support regarding it.
The size of the file you can download is governed by two things. How many, or rather the combined size of the uploaded images are included in the processed map and secondly, wrongly in my mind, the shape of the processed map.
I’ll need to dig out the emails, but unless things have changed, the max downloadable file at native resolution couldn’t be based on an upload of more than 7gb. Something like that. I’ll need to check.
The other thing, and the thing that winds me up, is that the diagonal shape of your map after you’ve exported, is text book why you can’t download native. The white blank area either side of it counts as processed map also and adds to its size. Even though there’s nothing there. It’s annoying that the processed export can’t be an image with the same dimensions and shape as the processed image, ignoring in the blank spots.
The only way I can think of to enable you to download that at native resolution, is to crop the file under ‘Map details’ under the Explore tab, export it as a smaller section, then move the crop to another section, export again and then stick back together in Photoshop or something. That’s how I’ve done it in the past.
One of my maps yesterday because of its size (70Ha), it wouldn’t allow me to export at anything less than 5cm/pix in one go. Drives me mad. Support acknowledged that it was a limitation of their system and that there was nothing they could do about it. That was a couple of years ago, but since I still suffer now, I guess the limitation is still there.
In my opinion the is very little reason why anyone would need to download anything better than a 2in/px unless you are working on really small project and just can. Most of our projects are 50ac and up and 2in/px is what we have found to be good enough for very accurate Bluebeam overlays while keeping the file still manageable by a normal computer. Most of the maps we fly are at 0.6in/px and occasionally I will download the 0.8in/px, but I feel like you hit a wall of diminishing returns and the overhead isn’t worth the very small gain. Just for clarification for those who don’t do metric a1.05cm/px is approximately 0.4in/px which is ridiculous unless you have a gaming computer once you pass that 50ac threshold and unless you are putting it into professional GIS or photo editing software on a 4K screen you’re probably not going to be able to see that resolution difference on the screen. I just exported 90ac at 0.8in/px, no problem.
Yup. Trying processing 10 miles of winding roadway that spanned about 10,000ac with the envelope processing. Needless to say nothing would export no matter what setting it was on so I ended up breaking it into 1-mile phases.
James, that’s answered everything perfectly - thank you. I suspected the blank area was contributing to the size.
As Michael suggests though, and I’m starting to realise (I’m new at this) the key is finding the ‘sweet spot’, by not trying to capture too many images in the first place for a project even if’s a large area (fly higher etc).
You’re workaround however if I do end up feeling like a could do with it slightly bigger is great. I’m happy to drag a few sections in Photoshop and join them that way.
Thanks James, much appreciated.
Yes agreed, thanks Michael. I’m going to capture the entire project again today at 65m rather than 45m. That should solve a few things at once: I’ll be able to complete all today (fingers crossed). It’ll process quicker. And I can download in one go. So I think the key here is work within the limits of DD until such time processes and outputs etc speed up. But as you say, does the client really need it? In my case the client wants to fill the wall with the image which is why I started ‘going big’. I’ll let you know how I get on. Feeling more confident today now!
Just keep in mind that you can use QGIS to stitch together orthos. They are georeferenced (which is the point of all this) and will drop right in on each other. Later on down the road if they want to see contour overlays and maybe some CAD linework we can walk through doing it there as well. You can even generate linework for someone to put back in CAD for planimetrics.
Just a report that I just exported 80ac at .65in/px, but it is barely usable in QGIS until I create pyramids. Exporting the tiles is another method that sometimes fixes large export problems and they naturally load into QGIS much better.
Here’s 255ac that I had to fly high to match how many batteries I had so it exports at 0.95in/px flown with the Yuneec H520. I still haven’t gotten use to the fact that they underestimate the batteries similar to DroneDeploy so they reported 3.5 batteries at 1 hour and it did it with two in 40 minutes with almost 5 minutes left so I could have brought it down another 25ft or so. Then it dawned on me that it’s because I am running the GiFi 7900mah batteries instead of the stock 5750’s. Anyways, check it out.
For some reason the model is not resolving fully…
Here’s the native image.