Litchi with interval timed photos

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Most missions I fly are used for orthophoto generation. As a result a typical flight will consist of multiple parallel flight lines with equispaced photos along each line (normally 60 or so in all)

I use a VBA application that I wrote to generate the Litchi flight plan as a CSV file which I upload via Mission Planner and this works well - until I decide that my photo spacing needs to be reduced. This means regenerating the whole thing again. Also with Litchi, when you take a photo at a waypoint it pauses a significant period at the waypoint before taking the photo, presumably to avoid ground smear in the resultant image.

In my case, at the altitude I fly (100m) and speed (10km/hour), ground smear is only a problem when shutter speed drops below about 1/200th second.

So I have been experimenting with using interval timed photos along a path which has only the end points of each flight line without intermediate points.

This works well in a semi automatic way - set the camera to interval timer mode (say 3 seconds), wait until the aircraft reaches the start of the first flight line, press the onscreen shutter button, wait until the end of the line, press again to stop the timer, wait until the start of the second line, press the shutter again to restart the timer and so on.

What I haven't been able to figure out is how to start/stop the interval timer automatically. I would have expected that when interval timer mode is set, the Take a photo action in the action list for a waypoint would start the interval time and subsequent Take a photo actions would toggle the timer.

This doesn't appear to be the case - from what I observed, even in Interval Timer mode, Take a Photo still takes a single photo just as it does when the camera is in single shot mode.

Does anyone know of any way to start/stop the interval timer automatically? I suspect this isn't possible but it seems an oversight that it is not.
 
Most missions I fly are used for orthophoto generation. As a result a typical flight will consist of multiple parallel flight lines with equispaced photos along each line (normally 60 or so in all)

I use a VBA application that I wrote to generate the Litchi flight plan as a CSV file which I upload via Mission Planner and this works well - until I decide that my photo spacing needs to be reduced. This means regenerating the whole thing again. Also with Litchi, when you take a photo at a waypoint it pauses a significant period at the waypoint before taking the photo, presumably to avoid ground smear in the resultant image.

In my case, at the altitude I fly (100m) and speed (10km/hour), ground smear is only a problem when shutter speed drops below about 1/200th second.

So I have been experimenting with using interval timed photos along a path which has only the end points of each flight line without intermediate points.

This works well in a semi automatic way - set the camera to interval timer mode (say 3 seconds), wait until the aircraft reaches the start of the first flight line, press the onscreen shutter button, wait until the end of the line, press again to stop the timer, wait until the start of the second line, press the shutter again to restart the timer and so on.

What I haven't been able to figure out is how to start/stop the interval timer automatically. I would have expected that when interval timer mode is set, the Take a photo action in the action list for a waypoint would start the interval time and subsequent Take a photo actions would toggle the timer.

This doesn't appear to be the case - from what I observed, even in Interval Timer mode, Take a Photo still takes a single photo just as it does when the camera is in single shot mode.

Does anyone know of any way to start/stop the interval timer automatically? I suspect this isn't possible but it seems an oversight that it is not.

Wondering if it would be possible to manually start photo interval mode at mission take off, add no command at each waypoint and then manually stop the photo interval mode at mission end? This might add some unwanted--and deletable--photos, but would eliminate the need to stop/start photos at each waypoint...

I'll set up a small (4 waypoint) mission and try with the P4P
 
Thanks dolphindancer. That's what I now do. I put a 2 sec pause at the first waypoint then, having set the timer mode, I manually press the shutter. Once the last waypoint is reached I stop the photos.

I normally set flight speed at 15 m/s and set the timer to 3 or 5 sec depending on altitude and the frequency of photos I need.

There are extra photos as the drone traverses from line to line which are easy to remove.

After the flight, I use a handy little program, BR's EXIF to create a .CSV file of all locations and file names. I then load this file into QGIS to overlay other GIS data. Note, if anyone tries this, BR's EXIF places an exclamation mark (!) as the first character on the first line (field names) of the .CSV file. I haven't the faintest idea why this is done but it screws up QGIS. This character must be removed before loading into QGIS.

Another handing technique is to point Picasa at the folder containing the photos, highlight them with the Locations side panel visible in order to visualise their locations.

As an aside, I routinely compress recorded images using JpegMini. This gives about a 2:1 compression without any discernible difference in quality.

When you load these compressed images into an orthophoto generator like Maps Made Easy it may complain. MME used to refuse to load them but will now, even though it sometimes that they are of poor quality. Why they say that, who knows, but despite the complaint the photos are processed without a problem.
 
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@Ian Gr I find myself planning litchi missions with Excel quite often, care to share your VBA app? Also for QGIS, (i'm sure you've found this by now) there is a plugin called Import Photos, just point it to a directory with your geotagged images and it will map them as a layer, I use this for every mission to ensure coverage.
 
@Ian Gr I find myself planning litchi missions with Excel quite often, care to share your VBA app? Also for QGIS, (i'm sure you've found this by now) there is a plugin called Import Photos, just point it to a directory with your geotagged images and it will map them as a layer, I use this for every mission to ensure coverage.

Happy to share the app with you but it is written for Access not Excel. I could look at converting to Excel but probably not for a few weeks.

And yes I now use Import Photos in QGIS. There was a problem a few weeks ago when after double clicking a few photo locations it stopped displaying the image. The most recent version of the plugin appears to have solved this.
 
Hi ... this is my first time posting .. please .. i need some help with interval shooting using Litchi. essentially I am unable to activate the shooting process. When I run a planned mission, a grid of parallel lines over an agricultural field, 60meters height @ 10kms/sec with interval shooting at 5 secs. here's the problem .. I am unable to activate any shooting .. pressing the right front button (the photo trigger) .. taks a picture .. but does not seem to activate the interval photo recording .. there is no on screen activity to confirm that there are pictures being taken ... looking back at the card, there are no pics ... so .. how do i activate the interval photo comand ? I am using a Mavic pro 2
 

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