when I look at the filmed material the image is choppy in 4K with 25 frames. I have no idea what it is I added a video to show what I mean I have an EVO II 8K
Choppy image
Choppy image
image is choppy when flying
- Thread starter Nlco574
- Start date
Most likely it's the low frame rate coupled with a high shutter speed. The 8K Evo II camera doesn't have an adjustable aperture, so to correct for this in strongly lit situations, you need to mount a neutral density filter on the lens. This effectively lowers the light transmitted to the sensor, which alllows for a longer shutter speed duration. A slower shutter speed causes a little motion blur to each frame whenever there's motion, thus tricking the brain into believing sequential stop motion images represent continuous analog reality. Ideally, you'll want to have a set of different strength ND filters on hand so that you can adjust the shutter speed to one-half the frame rate (e.g, 25 fps would be 1/50s shutter speed) no matter what the level of ambient light is.
What video editor did you use and what were your export settings? Looking at the YouTube stats for your video its dropping some serious frames which will cause choppiness. More than likely your bitrate was too high when you uploaded it to YT or your video editor caused the problems during export due to a mismatch in timeline frame rates, bitrates, or something else. Was the video choppy when playing back on your computer or was it fine until it was uploaded to YT? If it was choppy locally as well then you have something wrong in your editor's settings.
Within your video editor your timeline framerate must match your video framerate or be an exact mathematical multiple of your video framerate to prevent problems. When exporting you must use a YT compatible codec, a proper bitrate, and your export framerate must also match your timeline and framerate or be a mathematical multiple of your timelime framerate. If all of this does not line up, you will have the problems that you see in your video.
Google has posted a guide on the exact video settings, CODEC, container, bitrate, resolutions, etc. that work best for YT: YouTube recommended upload encoding settings - YouTube Help
I have proven countless times that the shutter speed cannot possibly cause choppiness. All the shutter speed does is affects motion blur...nothing more. I go into much more detail on this topic in this thread.
I also shot an entire example video with the shutter speed at 1/1000s or higher just to further prove that the shutter speed has nothing to do with stutter or choppiness in a video:
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I feel some contradiction in the answers. uploading didn't change the result. when I play the original material it gives the same problem. that's the reason I asked this question. I've always flown DJI and I've never seen the problem there. I used to film with ND filters and a shutter speed of 1/60 and an iso of 100. I will do some testing today to see if I can get a better result
If the source video footage is choppy then it could be your video card, or your video editor. Also, are you using the MOV container or the MP4 container? With DJI you were probably using H.264 for the compression codec and possibly 8bit as well. With Autel depending on your video container you could be shooting with H.265 for your compression codec and 10bit footage; much more difficult to play and edit. If you upload the raw clip to a file sharing site such as Google Drive and provide the download link I can download it and test it on my video editing PC. The clip would need to be straight out of the drone, not after you edit it in your editor.
I have many different video cameras and each one has different codecs, settings, and resolutions, so simply comparing DJI to Autel and saying it worked with DJI drones doesn't really tell me anything. To me it sounds like the footage out of your Autel is too high of a quality for your PC to properly playback or edit.
Also, answers to the following questions could help figure out the problem:
- Do you have a Windows PC or a Mac?
- Does the footage stutter even before you put it in your editor?
- What is your video editing software?
- If you have a Windows PC have you tried playing the raw clip in the Windows Video app? I have found raw Autel footage plays smoother in that app vs VLC
- What graphics card do you have in your editing computer?
For me the answer to the problem was very easy. I changed the frame rate from 25 to 30 and it is unbelievable but the problem is solved everything smooth. No ND filters used everything on automatic. Great drone the result with 4K is already fantastic. not yet tried 6K and even 8K.
Felix the Cat
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I was going to say pretty much the same. A microSD card with a write rate of V30 will not be able to handle the sheer amount of data that the drone is trying to force into it - result: choppy footage because the slow card has to dump data. For 4K: a card with a V90 rating should be the minimum if the drone transfers at approx 100mbps. 8K and I'd seriously look for a V120 write rating... Both V90 and V120 microSD cards are a lot more expensive: but if you want quality footage that reflects the quality of the drone camera: a cheap microSD card will shoot you in the foot every time. Look for Lexar or Prograde cards.
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MicroSD cards with a v30 rating are fine as long as they are high quality. I would never use a Lexar microSD card since they are very inconsistent quality. I have used Sandisk Extreme Pro v30 cards in every drone I've owned since 2014 and never had a problem. The drone only has a data rate of 100 Mb/s, the Sandisk Extreme Pro v30 cards support a data rate up to 130 MB/s which translates into 1,040 Mb/s so plenty of room for overhead.
People tend to get confused over Mb/s (Megabits per second) vs MB/s (MegaBytes per second). A MegaByte is 8 Megabits so to translate from MB to Mb you have to multiply Mb x 8. As you can see in this online calculator, 100Mb/s is only 11.9MB/s which is well below the v30 rating for Sandisk Extreme Pro v30 cards which is 130MB/s. Camera makers tend to use Mb/s because that's how the data rate is measured in the metadata of the video. Storage makers on the other hand tend to use MB/s because that's how storage throughput IOPs are typically measured; the consumer gets stuck in the middle with all of these confusing idiosyncrasies where it is easy to reach the wrong conclusions; don't even get me started on the complete mess that is USB standards.
MicroSD v90 cards tend to be very expensive and have less capacity than v30 cards; since the additional speed is not necessary I just stick to v30 cards. One of my cinema cameras has massive data rates when shooting raw and it does need v90 SD cards but no drone I've ever flown has needed that. The one nice thing about using v90 cards though is the much faster transfer times to your PC; assuming of course that you are using a fast enough card reader and USB SS port, otherwise those will be the bottlenecks. A nice feature of the Sandisk cards is they have a patented feature which lets you offload from the cards at close to v90 read speeds. So you have all of the benefits of v30 (lower cost, higher capacity), with some of the benefits of v60/v90 (faster offload speeds).
As far as stuttering goes, I highly doubt it is the card, typically when the data rate exceeds the card it just buffer overflows and the recording stops, or the metadata of the video gets corrupt and it is unplayable when you try to play it back later. Another symptom of a slow card is taking images and the buffer takes forever to clear (little spinning dial around the shutter button). Lexar media is the worst for this, which is why I would never buy Lexar cards.
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You don't know wtf you're talking about. A V30 write speed is 30 MB/s (Megabytes) and which is 8X that value, expressed in bits (Mbps). A V30 card has a minimum write speed more than twice the maximum bus/write speed of the Evo 2 series
Short of going the ND route, try setting the frame rate to 60fps for a diagnostic or even dropping into 1080p 120 fps. Or try shooting the last light of the day. If either appears to smooth things out, it's the shutter speed v. frame rate issue that's causing apparent clippiness.
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