Annoying Unsmooth, Judder when panning

BenKhaine

BenKhaine

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Ben Alfa
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Hello Everyone. I recently bought a Panasonic G7. It is amazing..... Well it was. I have recently noticed it judders when panning. I have read all kinds of posts and am aware of the 180 degree rule and 1/50 instead of 1/48 when shooting in 24FPS. I shoot in 25fps and have my shutter at 1/50 but i still get it. Its no use changing to another fps because i am shooting film and must use 24 or 25 fps. I cant remember the camera doing anything like this when i first got it.

I have reset the device and rendered it back to stock but still it persists. I must pan at about half the walking speed of an ant to avoid the judder.
I have tried it on my tripod, handheld (w and w/o stability), and shoulder rig. Its the same.
Tried at 24p and 25p. Its the same.
tried shutter speed at 40,50,60. its the same. a bit less at 40 but too much blur for my needs.

I have seen on facebook some fantastic pans faster than i am attempting on the g7 also but mine will not do it.

Is there some kind of option i have enabled which is taxing the cameras resources and somewhat retarding the data transfere freom the cmos?????

It does it in camera preview and in premier and windows media player. I am using 4k and this is also a must as it downsamples / downscales to 1080p really well and i also reposition shots.

Any ideas guys???
 
Sounds daft, and may have nothing to do with it, but could it be the SD? What is the write speed of the card you are using?
 
hello its a transcend sdxc 10 u3 64gb. r95 w60 MB/S. it does it while recording 1080p too.
 
Do you know what the bit rate of the camera is? 60MB/s write speed should be fine, but I'd want something a little quicker - the reason I say that is I know the GoPro records at 60mbps so imagine that would struggle. I'd imagine the G7 has a higher rate?
 
The Panasonic G7 is relatively rare in being able to shoot not just standard-definition or high-definition movies in-camera, but also ultra-high def movies. Topping out at the consumer 4K video standard of 3,840 x 2,160 pixels, the G7 uses MPEG-4 compression at a bitrate of 100Mbps, and offers frame rates of 24, 25 or 30 frames per second.
Click to expand...

http://www.imaging-resource.com/PRODS/panasonic-g7/panasonic-g7TECH.HTM

I imagine there's your problem.

Try lowering the quality/bit rate settings in camera and see how you get on.
 
Hi guys. The bit rate at 4k is 100mb per sec. I cant record at 50 fps because i am shooting movies and need to shoot at 25 or 24 fps. I did try 50 fps and it seemed much better but not movie like. There is no way of lowering the quality / bitrate in camera and this would only make the resulting video a lesser quality. I read the article you kindly sourced for me but i cant see what the problem may be that is stated in the article?????

The panasonic gh4 can use the same mbps rate and that pans wonderfully eventhough the g7 has a better more modern sensor (hahah yes i know the gh4 has more options, a higher bitrate and cinematic 4k), nevertheless, i have seen g7 pans on youtube that are smooth too. And at much faster pans than mine.
 
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The problem is, your camera is recording data at 100mbps, but your card can only write that data at 60mbps, so it's can't write the data quick enough - therefore losing some data/quality.

You need a faster card.
 
i dont think that there is a fasater card than the one i have. i will ccheck although i did before i bought it but thank you. you have given me a possible fix. I am thinking that my camera is broken somehow. i will check it now and let ya'll know. thank you very much. But my card is 60 MB/S not 60mB/s. this equals 480 mega bits per second. Almost 5 times more than required....................

Just checked it and the card certainly suffices. Also video needs a lot less write time as it has the record time to write data.

http://www.scantips.com/lights/cardspeed.html.

Neverthe less i will look into getting a faster card. But i dont think its the issue as it happens in 25p 1080p also
 
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BenKhaine said:
Hi guys. The bit rate at 4k is 100mb per sec. I cant record at 50 fps because i am shooting movies and need to shoot at 25 or 24 fps. I did try 50 fps and it seemed much better but not movie like.
Click to expand...
Shoot it at 50fps, apply the 180* shutter to get "movie like blur," and output it at 24fps if needed.

24fps is known for causing judder unless the pan is VERY smooth or slow. Try this link.
 
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thats very helpful thankyou, but in i need to shoot in 4k. the max output in 4k is 25. The judder is happening at 25p also. surely this can not be as out of the factory intended to be???
 
BenKhaine said:
thats very helpful thankyou, but in i need to shoot in 4k. the max output in 4k is 25. The judder is happening at 25p also. surely this can not be as out of the factory intended to be???
Click to expand...
It's just "physics"... when the fps matches the speed of motion it "stops," and then it starts again when they un-sync causing "judder." It happens to all cameras and it can happen at all fps. It's just that relatively slow fps will do it with relatively slow motions which is much more apparent to the viewer.
 
Im sorry to be a pain. But i think i need to state the problem again. I need to shoot in 4k. I shoot at 25p because of the inherent problems with 24p. The max output for 4k is 25p@100mbps. If i shoot at 50p it will be @1080p. This wont do. I use 1/50 shutter with 25p. I pan real slow. this is a link to a quick demo

View: https://youtu.be/p7G2JvpVljI


I never knew that this was an issue but doesnt seem to be with movies shown on youtube with my camera. I must say it again. This cant be normal. My camera is back to factory and is fine. My sd card is 60megabyte read andd 90 write. I tried other card but recording stopped as it wasnt fast enough. I can record 29:59 secs so my card is fine?

Detail goes away when moving but comes back when camera is still also.

Funny enough, my camera can handle slides perfectly but not pans????

Help!!!!!
 
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I'll be honest, I think you may have misread the SD Card. Surely it doesn't record at 60 magabytes per second. It must be 60 megabits per second
 
Looking on Amazon, and how the card you have is labelled, I'd say they've made a mistake in printing MB rather than Mb on the label of the card. Looking at the cards I own (SanDisk Extreme), the title says mbps, but the description says MB/s. Of course, there's a difference if it's written as Mb or MB (Megabit/MegaByte)

Speed issues aside, have you tried using other cards in case the one you have is a little duff?
 
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Just thinking outside the box a bit.

Are you using any form of image stabilisation?

I had the some concern when I first tried the video of my Nikon 1 series camera. Naively I just switched from still to video mode with VR still active.... panning just left the camera guessing what was going on then 'jumping' the image to the next 'stable' cycle. All in all it results in a jerky/jumpy video stream.
 
The point about IS that Barry makes is a good one. Another thing to note is that the pan in the posted example is still faster than the "7second rule" for 24p. 25p isn't much different, but it's better. And are you using a high quality fluid head for panning? I.e. are you certain that some of the jerkiness isn't actually in the panning motion?

And why do you insist that you need to shoot in 4k? There are very few systems that can actually play/display 4k well, 1080 is the max "HD" right now (anything on youtube will be 1080 max). And maybe that is your problem... try outputting your 4k video at 1080p. If the judder goes away then it's something in the playback chain that's not 100% compatible. In that case you could try a different player to see if it renders the 4k better (VLC and GoPro Studio are supposed to be better than some others).
 
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Thank you all very much for your Replies.

RandomlySet said:
Looking on Amazon, and how the card you have is labelled, I'd say they've made a mistake in printing MB rather than Mb on the label of the card. Looking at the cards I own (SanDisk Extreme), the title says mbps, but the description says MB/s. Of course, there's a difference if it's written as Mb or MB (Megabit/MegaByte)

Speed issues aside, have you tried using other cards in case the one you have is a little duff?
Click to expand...

Okay. I am willing to accept that this could be a mislabelling. If so, thats great. Is an SD Card not capable of recording at 60 megabytes per second??? I will purchase another even faster one and try again. Thank you so much.

chuckles said:
Just thinking outside the box a bit.

Are you using any form of image stabilisation?

I had the some concern when I first tried the video of my Nikon 1 series camera. Naively I just switched from still to video mode with VR still active.... panning just left the camera guessing what was going on then 'jumping' the image to the next 'stable' cycle. All in all it results in a jerky/jumpy video stream.
Click to expand...

I have tried with image stability on and off and with Vintage Legact Lens with no IS and the results are still the same.

sk66 said:
The point about IS that Barry makes is a good one. Another thing to note is that the pan in the posted example is still faster than the "7second rule" for 24p. 25p isn't much different, but it's better. And are you using a high quality fluid head for panning? I.e. are you certain that some of the jerkiness isn't actually in the panning motion?

And why do you insist that you need to shoot in 4k? There are very few systems that can actually play/display 4k well, 1080 is the max "HD" right now (anything on youtube will be 1080 max). And maybe that is your problem... try outputting your 4k video at 1080p. If the judder goes away then it's something in the playback chain that's not 100% compatible. In that case you could try a different player to see if it renders the 4k better (VLC and GoPro Studio are supposed to be better than some others).
Click to expand...

Yes I read of the 7 second rule in the article you sourced for me. I have tried much slower pan and the result is the same. The tripod i have is a photo one not filming one. But i have loosened it to the extent that the pans are smooth.
I insist on filming in 4k because when i downsample the 4k video. The resulting 1080p footage is so much better, clearer, smoother, the colour grading process takes and holds a lot better than if i grade a 1080p vid straihgt from camera. Also, i use 4k so i can simulate dolly shotts, re-postion footage and zoom without loosing quality. Rest assured that before i do anythink with the footage it is positioned and downsampled to 1080p before processing. So the PC is processing a 1080p file rather than a 4k one.

My workflow is:-

cameras 4k ----- Import footage into Premiere cc 2017 ------ Sequence settings to 1080p ----- Manually scale footage from 100% to 50% to fit in 1080p timeline ----- Reposition ----- Render ----- Snip and Size ----- Colour grade ----- Render.

This way i am not even playing back the 4k file really.
 
It doesn't help if you need 4K, but one of the 'features' of 4K is that it's best not to pan about so try to keep camera more or less still on an expansive or detailed scene.
Panning is not a good idea in any video unless unavoidable like following vehicles. If you watch TV with a technical eye it is rarely used except perhaps as an establishing shot.

I'n struggling to see how a barely coping card will cause this effect.
What does make a big difference is what you view results on.
My 4K TV plays video much more smoothly than Laptop or PC and you especially notice lack of jerkiness in any panning.
 
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Okay. I think i concede. It must be a combo of my low quality stills tripod head, my speed of panning and the fact that i should not pan in my mivies. But i still cant understand why youtube vids of g7 and g7 with zhion crane M are so smooth??????

But i will have to come up with another way of establishing my location in my films. Thank you all for your great advice and im glad to be part of the clique.
 
Firstly, the pan is not smooth.

Secondly, the perceived judder is proportional to the spatial frequency of the display - this is directly related to the pixel count. So if you move from HD to UHD but keep the frame rate constant, the motion artefacts increase.
 
gees thanks guys. i got a whole lot of reading and research to do over the weekend. I love theory and anything to improve my filming. Again thank you aal.
 
Some Panasonic lenses have issues operating with the image stabilisation, particularly when panning, this results in a phenominum called "micro jitter" If possible try a lens of a different focal length to see if the problem persists.
Panasonic have also issued firmware updates for certain cameras, so it might be worth checking that your up to date.
And finally, I personally would never, ever, ever even touch a transcend memory card, I strongly recommend you pay a little extra and get a sandisk extreme pro sdxc card, they are well worth the investment.
 
RandomlySet said:
Looking on Amazon, and how the card you have is labelled, I'd say they've made a mistake in printing MB rather than Mb on the label of the card. Looking at the cards I own (SanDisk Extreme), the title says mbps, but the description says MB/s. Of course, there's a difference if it's written as Mb or MB (Megabit/MegaByte)

Speed issues aside, have you tried using other cards in case the one you have is a little duff?
Click to expand...

SD card read/write speeds are measured in megabytes per second.
https://www.sandisk.co.uk/home/memory-cards
 
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