Phantom 4 Advanced for surveying and mapping

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Good evening all,

Today I used third party software such as pix4d to fly a grid mission with my phantom 4 advanced.
Majority of the images are blurry except the ones at the end of the grid.

in DJI Go4 app, I had set the settings to auto detect the required parameters before the flight.
Within the clear images I am noticing the same shutter speed as the ones in unclear ones.
Within the clear images I am noticing same f-stop setting but ISO settings and different aperture.

What would be the problem here?
Is it that my SD card is not fast enough between successive image acquisition?
Or is it that my P4A is not able to focus fast enough while in flight and it is throwing such blur on my image?

Those with experience, please share your advise. Any comment or suggestion is welcome!

Best,
-Ethan
 

Meta4

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Today I used third party software such as pix4d to fly a grid mission with my phantom 4 advanced.
Majority of the images are blurry except the ones at the end of the grid.

What would be the problem here?
Is it that my SD card is not fast enough between successive image acquisition?
Or is it that my P4A is not able to focus fast enough while in flight and it is throwing such blur on my image?
The SD card cannot cause images to be out of focus.
The same drone/camera has no problem taking a couple of hundred well focused images when flying a Dronedeploy mission.
So the SD card and camera focus speed are not the problem.
in DJI Go4 app, I had set the settings to auto detect the required parameters before the flight.
As long as the lens is not focused at the near end of the focus range, the lens has so much depth of field that focus hardly matters.
If it was focused at 3 ft distant objects would be out of focus.
in DJI Go4 app, I had set the settings to auto detect the required parameters before the flight.
Do settings in DJI Go carry across to Pix4D?
Does Pix4D have focus settings of its own?
Within the clear images I am noticing the same shutter speed as the ones in unclear ones.
Within the clear images I am noticing same f-stop setting but ISO settings and different aperture.
What differences do you observe in ISO and aperture?
It would probably be better to set the camera to shoot in Aperture Priority and a use a fixed ISO value for this sort of mission.
 
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The SD card cannot cause images to be out of focus.
The same drone/camera has no problem taking a couple of hundred well focused images when flying a Dronedeploy mission.
So the SD card and camera focus speed are not the problem.
That does make sense! I have this SD card listed here: http://shop.sandisk.com/store/sdisk...parentCategoryID.11442400/CategoryID.58895400
And it seems to meet the criteria.
As long as the lens is not focused at the near end of the focus range, the lens has so much depth of field that focus hardly matters.
If it was focused at 3 ft distant objects would be out of focus.
In DJI Go app I had set the settings to auto focus, flying at 80m AGL, shouldn't it focus accordingly? One thing I have noticed is that before and after the firmware upgrade, when I am viewing live feed on my iphone, video is much clearer than image. This is noticeable when I switch between the option to take video or capture single image in DJI go app. Why would such happen? If lens was out of focus then it wouldn't take any clear images, but it takes some sharp images and rest are bad.
Do settings in DJI Go carry across to Pix4D?
Yes Pix4D inherits settings from DJI Go app. The only thing Pix4d does is that it ensures that focal length does not change throughout the mission and that at given intervals the pictures are taken.
Does Pix4D have focus settings of its own?
No Pix4d does not have focus settings of its own.
What differences do you observe in ISO and aperture?
Please have a look at sequence of image that I have uploaded from 236 to - 244.
Image 238 and 239 is where the P4A makes two 90 degree turns.
It would probably be better to set the camera to shoot in Aperture Priority and a use a fixed ISO value for this sort of mission.
I will surely give that a shot. I also own Mavic Pro and I have tried the same mission with its auto settings, the same images from both UAVs are very different. Have a look at images 130-133 those are from mavic. I cannot upload on this post so hopefully I can upload in my next reply.
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Here are the images from Mavic Pro, absolutely clear ones at default autofocus settings while using Pix4D app.
When I try the same with P4A, the results are nowhere close.
 

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Meta4

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Within the clear images I am noticing the same shutter speed as the ones in unclear ones.
Within the clear images I am noticing same f-stop setting but ISO settings and different aperture.
What differences do you observe in ISO and aperture?

Looking at the images, I suspect they were taken in dull light as there are no shadows.
Above ISO 400, you tend to get a lot of noise that gives a dull fuzzy/grainy effect
What are the shutter speeds and ISO values for the images you posted?
 
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What differences do you observe in ISO and aperture?

Looking at the images, I suspect they were taken in dull light as there are no shadows.
Above ISO 400, you tend to get a lot of noise that gives a dull fuzzy/grainy effect
What are the shutter speeds and ISO values for the images you posted?

Hi Meta4,

That is correct. It was a cloudy day. And majority of the images including the sharp ones are taken at 230-400 ISO.
Shutter speeds for the images are automatically set by DJI GO4, they all are at 1/30 of a second.
 

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