Support Website Contact Support Blog

Phantom 4 Pro Rolling shutter effect

Hello!

 

recently I am having problems getting good pictures with my P4Pro using Pix4D Capture. The pictures are blurred/having an rolling shutter effect. The problems could be related to the poor lighting conditions of winter. What can i to mitigate the problem? The P4Pro should have a mechanical shutter so it shouldn’t suffer from the rolling shutter problem?

 

Best regards,

Romel

1 Like

Aloha Romel, 

Try capturing the images in “Safe mode” rather than Fast mode.  Safe Mode will have the drone stop at each photo location which should help improve the image quality.  I believe your images are coming out blurry due to movement of the Drone while taking images.  When you are taking images in poor lighting conditions, the Shutter speed is normally “slowed” which leads to blurring if the drone is in motion during photo capture.

Please let me know if this improves your images.

Hey Aaron,

thanks for the swift answer. I think you are onto something there :slight_smile: How can i activate safe mode? If it matters i’m using an Samsung S2 8" tablet.

Best regards,

Romel

In the Pix4Dcapture App, you can set the Drone Speed to Slow versus fast under the Settings Menu (Gear like Icon in upper Right of window)

Hello again,

i went on friday and tried the slow(est) speed setting, but the results are the same.

The drone did stop for a few fotos, but most pictures where still taken midflight.

I have a few samples:

https://www.upload.ee/image/7732472/DJI_0123.JPG 

https://www.upload.ee/image/7732478/DJI_0147.JPG 

Not all pictures are affected, some are ok, but most are unusable.

Any advice is welcome, I am already behind with my projects and have no solution at the moment.

Edit: Also Pix4d shows the shift, shown here:

https://www.upload.ee/thumb/7732544/Pix4d.jpg 

Best regards,

Romel

Hi Romel,

We notice that the images are blurry and the first step (reducing the speed) needs to be combined with custom camera settings. In this specific dataset, the images have 1/30s exposure which is significantly too long. As a comparison, it is hard to take a sharp image with 1/30s exposure even while handheld shooting that does not have all the influence of drone vibrations. 

At the moment we recommend you to have a look at the following article and adjust the setting (e.g. exposure, ISO) in order to get better images. More here: https://support.pix4d.com/hc/en-us/articles/203204339 

Best,

Hello,
I have the same problems. The Phantom 4 pro is also flying too fast at the speed-setting SLOW: more than 7 m/s.
I’m sorry, but the next text is written in german.

Ich fliege mit der Drohne DJI Phantom 4 pro. Seit kurzem fliegt die Drohne beim Flug eines rechtwinkligen oder polygonalen Rasters viel zu schnell. Bei der Einstellung slow fliegt sie mind. 7 m/s. Fotos sind dadurch unscharf.
Das hat sie vor einigen Wochen/Monaten nicht getan. Da flog sie bei ungefähr mittlerer Einstellung deutlich langsamer.
Ich habe sie mit 2 verschiedenen Samsung smartphones gesteuert.
Software und Hardware sind auf dem aktuellen Stand.

Schön wäre übrigens, wenn die Fluggeschwindigkeit als Zahl eingestellt werden kann. Die Flughöheneinstellung wäre in 5m Schritten besser.
Ferner wäre eine Continuefunktion eines Flugplanes hilfreich. So könnte man ein großes Projekt planen, bei schwacher Akkuleistung den Flug abbrechen und nach dem Akkuwechsel an gleicher Stelle fortführen.

Über eine Rückmeldung würde ich mich freuen.

Mit freundlichen Grüßen
Olaf

This bug will be fixed in the next release; reducing the speed slider should always result in a lower speed except, perhaps, if the drone autopilot is not capable of flying slower.

I have forwarded your request to add a numerical value for the drone speed. As a side note, we encourage users to post the future request here: Product feedback.

The mission resume option is already available on the Android version of the app. More here: Mission resume and multi-battery flights.

Best,

 

The Phantom 4 Pro has a global shutter?  That doesn’t appear to be what their website says.

@Brian, could you send us the link to the website you are mentioning?

Phantom 4 Pro has Global shutter, but you can also use electronical shutter. Check the settings you are using in DJI Go app

Blaz

The website is just the specs page for the Phantom 4 Pro.  https://www.dji.com/phantom-4-pro/info#specs

It does say that the P4P has a mechanical shutter.  It does not say it has a global shutter.  From everything I’ve read nearly all inexpensive CMOS sensors capture images line by line whereas CCD’s will have global shutters.  I expect that if they did have a global shutter in the P4P they would be advertising the heck out of that fact as Canon, Sony and Panasonic have.  

In contacting DJI support to try to get some clarity on this issue they eventually responded that the P4P CMOS captures images line by line as you would expect from an inexpensive CMOS sensor.  

So I’m left to think that the P4P has a mechanical shutter over the top of a CMOS sensor that captures images line by line (rolling) which should take some period of time between 30 - 74 milliseconds to record an image. (See Pix 4d Rolling Shutter correction page)

I expect there is something I don’t understand here that causes the mechanical shutter of the P4P to be superior for mapping.  Maybe DJI has in fact created a global shutter CMOS but if they have I don’t understand why they bother with the mechanical shutter at all.

I’ll go right out and buy a P4P or Inspire 2 with X4S if I can convince myself they are better for mapping but so far I’m confused.

Brian

PS:  A discussion of mechanical vs electronic vs global shutters:  http://www.red.com/learn/red-101/global-rolling-shutter

 

1 Like

Phantom 4 pro uses Mechanical shutter when taking stills if you enable it in Go app. Electronic shutter is used for video. P4P uses mechanical leaf shutter

Here you can read more about the differences  https://www.juzaphoto.com/article.php?l=en&t=mechanical_and_electronic_shutter

 

Here’s a thread about it: https://phantompilots.com/threads/mechanical-rolling-shutter-tests.97502/

 

1 Like

I believe that the confusion stems from the fact that the presence of a mechanical shutter does not always guarantee that linear rolling shutter distortion is not present in an image. In fact, the sensor in the DJI Phantom 4 Professional camera is a CMOS sensor that records each image line-by-line, as Brian mentioned, which is typical for a rolling shutter , and not “all at once” which is characteristic of a global shutter.

For additional information about the camera sensor and the shutter itself, we recommend contacting your camera’s manufacturer directly.

We have reason to believe that whatever rolling shutter distortion that may be present in images captured by DJI’s Phantom 4 Professional is, generally speaking, marginal and should have little to no effect on your project results.

However, if you see any symptoms in your project that are commonly due to excessive amounts of linear rolling shutter distortion in your images, e.g. your results bending or an extreme difference between your camera’s initial and computed internal camera model parameters, etc., we recommend the following:

  • Enable the linear shutter optimization in the Image Properties Editor and then process step 1. Initial Processing again.
  • Capture the project area again while flying slower and/or higher above the ground to reduce the amount of linear rolling shutter distortion that is present in your images. You can see how your camera and flight parameters influence the amount of linear rolling shutter distortion that is present in your images with Pix4D’s Vertical Pixel Displacement Calculator.
  • Ensure that the Mechanical Shutter option in DJI GO 4 is enabled for all future flights. Please note that enabling this option does not guarantee that all images will be captured using the mechanical shutter due to limitations of the mechanical shutter’s exposure time and other factors.

Please do not forget that it is not possible to identify the presence, absence, or amount of linear rolling shutter distortion that is present in an image simply by looking at it. A common misconception is that a blurry image is caused by rolling shutter distortion. The geometric distortions that are introduced into an image by a linear rolling shutter cannot be identified accurately by the human eye so if you have a camera with a linear rolling shutter and do not have a general idea of how much distortion is present in your images, we recommend that you at least estimate how much distortion is present with Pix4D’s Vertical Displacement Calculator.

To be clear, the factors that influence the amount of linear rolling shutter distortion in an image are not the same factors that influence whether an image is blurry.

Blaz

So it appears we the position of Pix 4d is that the mechanical shutter in the Phantom 4 Pro and Phantom 4 RTK is actually not beneficial for mapping in any way?  This makes intuitive sense to me but it’d be nice to hear from the experts.