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Don't trust the M3E speed on Pilot2 for mapping missions!

mikegrad

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So I ran some tests today because my last mapping mission photo quality was not up to par. I created the mission, from 125ft, 80/80, for the m3E, and the default speed was like 18mph. Which sounds great, and I'm thinking with the mechanical shutter this will be fine.. WRONG.

photos were quite blurry. You dont notice it at regular viewing, but when you zoom in its apparent. My client definitely noticed it. So i thought maybe something was wrong with the drone, so i want a test mission at 18mph (Test1), 12 mph (test2), and 4 mph (test3). results attached. I think 12 mph is a safe speed, but will probably drop it down to 8 just to be safe. Just thought i would share my findings with the group. If you have any other comments on the photos themselves, or suggestions, i would be happy to hear them!

EDIT - test2 and test3 are too big for this forum, and i dont want to change them, so google drive link to see all 3. I added an original photo from the actual client work as well.
To really see it at max zoom you need to download the photos locally, not just zoom in from google drive.

 

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Are the images looking like this without doing a mission?
 
good point. as I look further at these, the original ones taken are far worse. i added a Wide1 and Zoom1 photo to the drive - those were stills with the drone hovering at 125ft
I don't think the zoom and the wide look as bad but still not sharp. I don't think camera settings have anything to do with it. So, if it were me, I would contact DJI and see what they say. You have a lot of money invested in that and should be getting better images.

However, there may be others here that can shed light on it as well.
 
So I ran some tests today because my last mapping mission photo quality was not up to par. I created the mission, from 125ft, 80/80, for the m3E, and the default speed was like 18mph. Which sounds great, and I'm thinking with the mechanical shutter this will be fine.. WRONG.
Having a mechanical shutter doesn't make your images any sharper when you are flying a mapping mission.
Having a good fast shutter speed makes your images sharper.

photos were quite blurry. You dont notice it at regular viewing, but when you zoom in its apparent. My client definitely noticed it. So i thought maybe something was wrong with the drone, so i want a test mission at 18mph (Test1), 12 mph (test2), and 4 mph (test3). results attached. I think 12 mph is a safe speed, but will probably drop it down to 8 just to be safe. Just thought i would share my findings with the group. If you have any other comments on the photos themselves, or suggestions, i would be happy to hear them!

EDIT - test2 and test3 are too big for this forum, and i dont want to change them, so google drive link to see all 3. I added an original photo from the actual client work as well.
To really see it at max zoom you need to download the photos locally, not just zoom in from google drive.
There's nothing wrong with the speed of the drone, I've done many mapping missions at much higher flight speed.

The reason your original image is softer is because it was shot at 1/100th f8 and the others were shot at 1/500th or 1/350th at f2.8.
1/100th is not fast and shooting from a moving camera at a slow shutter speed has caused some motion blur.
Your height is also quite low for mapping, which makes the movement of the scene across the frame faster than if you flew higher.

If you want sharp images, don't shoot at an aperture that requires a 1/100th shutter speed.

And I have to ask, just in case .... Was the light fairly dull?
Or did you have an ND filter fitted to the lens?
 
I think Meta4 hit it on the nose. In fairly bright sunlight (as these appear to be) you should be able to shoot f4 1/500 sec 200-250 ft (usually recommended by Drone Deploy etc.). ND filters are NOT to be used for photos (if that was the case), but rather for video to slow down the shutter speed to have some motion blur instead of sharp images.
I do disagree, however, in that the mechanical shutter generally does help cut down on motion blur (IMHO).
 
I do disagree, however, in that the mechanical shutter generally does help cut down on motion blur (IMHO).
A mechanical shutter is better but the OP's issue is not caused by using an electronic shutter.
An electronic shutter can result in motion distortion with very fast movement, but it normally doesn't cause a significant problem in mapping as all the people who have used the Mavic 2 pro for mapping know.
 
ive done a few more experiments, and a reshoot. The original shoot was in auto mode. i don't have any idea why it would choose 1/100 shutter. On my re-shoot, i lowered the speed to 8mph, and a second run at 5 mph. similar lighting conditions. all using DJI's Pilot2. I haven't had the chance to install dronedeploy yet for the m3E.

these second runs are much better, but DJI doesn't maintain a constant shutter speed in auto. its ranging from 1/350 to 1/1000. i think the next run will have to be manual settings to maintain a constant set of parameters. i was also able to bring the altitude down to 95ft. this is because the client wants the clearest zoom in possible.

I added the latest photos to the drive for review. the shutter speed is all over the place

 
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ive done a few more experiments, and a reshoot. The original shoot was in auto mode. i don't have any idea why it would choose 1/100 shutter.
It sounds like you don't have a great photographic understanding.


On my re-shoot, i lowered the speed to 8mph, and a second run at 5 mph. similar lighting conditions.
There is no need to fly at a snail's pace for mapping.
8 mph is much too slow and would limit you to mapping very small areas.
I usually run mapping flights at 20 mph or faster.

What were the lighting conditions?
You need good light to be able to use faster shutter speeds.
Your exposure settings are suggesting quite low light levels.
Was the light quite low or did you have an ND filter on the lens?

DJI doesn't maintain a constant shutter speed in auto. its ranging from 1/350 to 1/1000.
That's not necessarily a problem (as long as they are fast enough).
Your shutter speed is all over the place because the amount of light and dark in the frames is all over the place.
Your camera was varying the shutter speed to give correct exposure.

i think the next run will have to be manual settings to maintain a constant set of parameters. i was also able to bring the altitude down to 95ft. this is because the client wants the clearest zoom in possible.
Unless you know what you are doing with the camera settings, you are likely to have problems when you start changing settings.

It's clear that your photographic understanding isn't great and you've not done mapping before.
Drone mapping can be complicated.
To achieve good mapping results, you really need to understand photographic exposure and not just guess and make random setting changes.
You also need to have done some practise mapping so you know what works and what doesn't and how to get the results your clients want.

I don't think it's a good idea to accept a commission for something you've never done and hope you get acceptable results.
Perhaps you needed to turn down this job and get some experience first?






 
You are going to have to experiment with your camera settings and like Meta said learn a little on your exposure triangle.
A decent video explaining mapping settings.


I use Shutter Priority, Shutter 1000 to 1600 and let the aperture change for the different lighting of each image. I also use White Balance Grasslands.



My Phantom 4 RTK cannot fly as fast as your M3E while mapping due to it not being able to write the images fast enough, but I always use the max speed and my images are never blurry unless there was a focus issue.
 
So I ran some tests today because my last mapping mission photo quality was not up to par. I created the mission, from 125ft, 80/80, for the m3E, and the default speed was like 18mph. Which sounds great, and I'm thinking with the mechanical shutter this will be fine.. WRONG.

photos were quite blurry. You dont notice it at regular viewing, but when you zoom in its apparent. My client definitely noticed it. So i thought maybe something was wrong with the drone, so i want a test mission at 18mph (Test1), 12 mph (test2), and 4 mph (test3). results attached. I think 12 mph is a safe speed, but will probably drop it down to 8 just to be safe. Just thought i would share my findings with the group. If you have any other comments on the photos themselves, or suggestions, i would be happy to hear them!

EDIT - test2 and test3 are too big for this forum, and i dont want to change them, so google drive link to see all 3. I added an original photo from the actual client work as well.
To really see it at max zoom you need to download the photos locally, not just zoom in from google drive.

I had this problem once, but corrected it immediately. It's all about how bright the day is and the shutter speed. You must always lock your shutter speed to 1/500 to 1/2000 if you want to fly at high speed. The brighter the day, the better. Low ISO and high shutter speed.

My problem arose when my shutter speed was on auto. The day was dim and the shutter speed dropped, causing lots of motion blur.
 
My problem arose when my shutter speed was on auto. The day was dim and the shutter speed dropped, causing lots of motion blur.
There's nothing wrong with allowing auto-exposure to judge the correct shutter speed, as long as there is reasonably good lighting and the drone isn't too low.
The OP had some poor exposure settings (aperture at f8 causing a slow shutter speed) was flying at 125 ft which would cause more movement of the subject within the frame.
 
It sounds like you don't have a great photographic understanding.



There is no need to fly at a snail's pace for mapping.
8 mph is much too slow and would limit you to mapping very small areas.
I usually run mapping flights at 20 mph or faster.

What were the lighting conditions?
You need good light to be able to use faster shutter speeds.
Your exposure settings are suggesting quite low light levels.
Was the light quite low or did you have an ND filter on the lens?


That's not necessarily a problem (as long as they are fast enough).
Your shutter speed is all over the place because the amount of light and dark in the frames is all over the place.
Your camera was varying the shutter speed to give correct exposure.


Unless you know what you are doing with the camera settings, you are likely to have problems when you start changing settings.

It's clear that your photographic understanding isn't great and you've not done mapping before.
Drone mapping can be complicated.
To achieve good mapping results, you really need to understand photographic exposure and not just guess and make random setting changes.
You also need to have done some practise mapping so you know what works and what doesn't and how to get the results your clients want.

I don't think it's a good idea to accept a commission for something you've never done and hope you get acceptable results.
Perhaps you needed to turn down this job and get some experience first?
What a pep talk! 👏 glad we have community members like you to ALWAYS make sure to tell others of their failures. We all started somewhere. This forum is for asking for help to learn....if you have no helpful input in the matter why the **** do you have input? You get experience by DOING. Thats what he's trying to do. Be helpful. Or be gone. Thats what this is for.

You map @ 20mph?
Post a pic of one of those 20mph 115ft orthos then. Im here asking the same question,8-9 mph is safe- blurryness at higher speeds- can I cut this mission time down if it has the mechanical shutter and no way to lock down the shutter speed since it changes based on the lighting etc.?
 
This forum is for asking for help to learn....if you have no helpful input in the matter why the **** do you have input?
You get experience by DOING. Thats what he's trying to do. Be helpful. Or be gone. Thats what this is for.
You might not agree but I did give a lot of help to the OP.
You map @ 20mph?
Yes ... and faster too.
Post a pic of one of those 20mph 115ft orthos then.
I can't because I'd never fly at 115 ft for a mapping project.
It's much too low.

Im here asking the same question,8-9 mph is safe- blurryness at higher speeds- can I cut this mission time down if it has the mechanical shutter and no way to lock down the shutter speed since it changes based on the lighting etc.?
It's not important to "lock down the shutter speed".
If you can explain what question you want answered, I'll try to help you with it.
 
I routinely map at 20. Also, 150-170 is the sweet spot for the GSD most projects need, 115 would make even the simplest project take 2x to 3x the time which is not sustainable.
 

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