Slow Motion Video Problem

[Anjin San]

Or…maybe it's an Anjin-San problem and not a video problem

OK…I'm a video novice but in getting ready for my trip to Africa the end of the month I'm making sure I can at least shoot some and take some baby steps into video for the blog. I set up my Z8 for 4K/120 as this allows 4x slow down if needed in post or I can just export at 120 for real time speed use. Output mode is H.265 10 bit MOV and I've got a hot shoe mike to use.

So…recorded a video of my wife practicing her music and then copied it over to my MBP. Playing it in either Quick View or with QuickTime Player…it got normal speed for 10 or 15 seconds than just slows down. Same results if I import it into iMovie which I'll use for now. Recording from my Z7II set up the same way at 4K/30 except that it's just MOV so I think it's only 8 bits plays back just fine.

Any idea why this is going on and how to fix it? I could just shoot 30 and slow down in iMovie…but it looks like that just doubles every frame for 50% and quadruples for 25% and I'm sure that the 120 FPS would give a better overall video…but maybe it doesn't and one of you video experts can 'splain it to me.

Thanks.

 

[ricardo00]

Or…maybe it's an Anjin-San problem and not a video problem

OK…I'm a video novice but in getting ready for my trip to Africa the end of the month I'm making sure I can at least shoot some and take some baby steps into video for the blog. I set up my Z8 for 4K/120 as this allows 4x slow down if needed in post or I can just export at 120 for real time speed use. Output mode is H.265 10 bit MOV and I've got a hot shoe mike to use.

So…recorded a video of my wife practicing her music and then copied it over to my MBP. Playing it in either Quick View or with QuickTime Player…it got normal speed for 10 or 15 seconds than just slows down. Same results if I import it into iMovie which I'll use for now. Recording from my Z7II set up the same way at 4K/30 except that it's just MOV so I think it's only 8 bits plays back just fine.

Any idea why this is going on and how to fix it? I could just shoot 30 and slow down in iMovie…but it looks like that just doubles every frame for 50% and quadruples for 25% and I'm sure that the 120 FPS would give a better overall video…but maybe it doesn't and one of you video experts can 'splain it to me.

Thanks.

I have been waiting for someone else to comment. But it isn't you, my camera does the same. My "solution" is, I turn on the video early. I actually have learned to like the original normal speed and showing the slow down. Have a great time in Africa and look forward to seeing the videos that you get!
For example:

 

[ElenaH]

@Anjin San
I use the same set up as you use. So, I shoot in Africa with 4K/120fps and H.265 10bit. Then I go through my clips using Quick Time Player and have the same appearance (first normal sped , then slower). Quick Time is not a software for processing your footage but only a player so, it plays back as it is recorded. Perhaps, there are some setting where you can definde with fps to use for play back. I just play the clips faster. I use it only to trim and to make a selection.

For processing I am using Final Cut Pro where I define the fps for the end-result and it is used in timeline. I don't know if you can definde fps for timeline in iMovie. Perhaps.
When fps for timeline is set (let's say 30fps) then all clips are shown in this fps and not slowed down. But you can make a slow moting if you have shoot in 60 or 120fps.
If my footage is 120fps than I can slow it down 4x actually. It idefinitely makes sense to take footage in 120fps IMO.
You just need to use a better sodtware for processing. For example, Davinci Resolve. I think it has a free version.

Wish you a nice trip!!

 

[Nimi]

Or…maybe it's an Anjin-San problem and not a video problem

OK…I'm a video novice but in getting ready for my trip to Africa the end of the month I'm making sure I can at least shoot some and take some baby steps into video for the blog. I set up my Z8 for 4K/120 as this allows 4x slow down if needed in post or I can just export at 120 for real time speed use. Output mode is H.265 10 bit MOV and I've got a hot shoe mike to use.

So…recorded a video of my wife practicing her music and then copied it over to my MBP. Playing it in either Quick View or with QuickTime Player…it got normal speed for 10 or 15 seconds than just slows down. Same results if I import it into iMovie which I'll use for now. Recording from my Z7II set up the same way at 4K/30 except that it's just MOV so I think it's only 8 bits plays back just fine.

Any idea why this is going on and how to fix it? I could just shoot 30 and slow down in iMovie…but it looks like that just doubles every frame for 50% and quadruples for 25% and I'm sure that the 120 FPS would give a better overall video…but maybe it doesn't and one of you video experts can 'splain it to me.

Thanks.

Welcome to the Rabbit-hole...

It's you , not the camera.

You can shoot 4/120 and then edit it in iMovie by selecting the clip in the timeline and pressing the Speed button or selecting Change Speed in the Modify pull-down menu. 120 allows you to slow it down 5x before getting into trouble (to 24fps). The other way is to shoot it slow motion, which is 8-bit vs. 10 so just don't have sky in the scene to avoid banding. It might be good enough especially if you're not planning to mess with it too much (like bringing up the shadows).

As Elena pointed out, QuickTime is just a viewer. It automatically slows the display to 24 or 30 fps after a couple of seconds which is what you're seeing.

Final note: 4k/120, Africa, Z8 - watch out for memory, battery and overheating.

Have a great trip and looking forward to seeing your photos and videos. If you have any questions that go beyond a post, send me a DM or give me a call.

 

[Nimi]

I have been waiting for someone else to comment. But it isn't you, my camera does the same. My "solution" is, I turn on the video early. I actually have learned to like the original normal speed and showing the slow down. Have a great time in Africa and look forward to seeing the videos that you get!
For example:

See my reply to Anjin San. It's not supposed to be displayed like this and can easily be edited in whatever editor you are using. If you like the effect of going from normal to slow-mo, Google "speed ramping" and it will show you how to change it to a smooth transition.

My slow motion workflow is shooting at 4k/120, dropping it into a 24fps timeline (set in Preferences), selecting the clip, changing clip speed to 24fps which makes the clip 5x longer, removing the sound by unlinking and deleting, then set my ins and outs, do the rough cut, then color correct and grade. I never speedramp.

 

[ricardo00]

See my reply to Anjin San. It's not supposed to be displayed like this and can easily be edited in whatever editor you are using. If you like the effect of going from normal to slow-mo, Google "speed ramping" and it will show you how to change it to a smooth transition.

My slow motion workflow is shooting at 4k/120, dropping it into a 24fps timeline (set in Preferences), selecting the clip, changing clip speed to 24fps which makes the clip 5x longer, removing the sound by unlinking and deleting, then set my ins and outs, do the rough cut, then color correct and grade. I never speedramp.

Thanks, I will check it out.

 

[realspeed]

I had the same issue, recording in 4k MOV and trying to watch on an editing suite that does not recognise this format. The answer is to use maybe What I use
that is " wondershare Filamor or Movavi video editor plus 2022" editing suites. Either that or record in MP4 instead. that will get your issue solved

 

[Anjin San]

I'm going to just answer all comments in one reply instead of several. Short answer…I figured out how to solve the problem and it appears to be an obscure Apple bug which I'll report to them for possible fixing.

Thanks for all the good wishes on the trip…and fate willing and with Steve's and the guide's help I'm sure we'll have a fab time.

-Turning on the video early doesn't help to solve my actual desire which is to have a 120 FPS movie that I can use as is or slow down as needed and then output a 30FPS file for the blog or whatever.

-I will probably eventually shift to either Final Cut Pro or DaVinci if I decide I need the more advanced capabilities; but at this point I'm going to stick with iMovie as it does what I want to do. I did download and try DaVinci free version…and the extra unneeded capabilities at this point just make it more cumbersome to use.

-I did more testing today and here's what happens…and it doesn't matter whether the movie format is 8 or 10 bit. Recored at 4K120 and then moved to my MBP running Sonoma…QuickView in Finder displays the video correctly most but not all of the time. Opening in QT Player…which I realize is just a player…always results in 15 or so seconds of normal speed then it slows down to half speed. Pulling the downloaded movie file into iMovie and then dragging to the timeline then clicking on Preview does the same thing within iMovie and exporting results in a file that does the same in QT Player as the original file. Undaunted by this…I installed DaVinci and dragging the movie into it…previewing the file it plays properly and also the exported from there version plays properly. So…knowing I had a solution if I needed it I went back into iMovie and noticed that in the menu where you select slo mo or fast forward there is also a Reset Speed command which was grayed out. So I selected the clip, set it to half speed, then selected the Revert Speed menu item. At that point…the file previews in iMovie just fine and the exported version at 30FPS works just fine as well. More testing revealed that selecting 2X fast forward and then Revert Speed has the same results so the output file plays as expected. So…round about way of solving the problem…but it works.

-I'm not sure why QT slows down playback on its own…seems to me. that if you feed it a file it ought to honor the file contents and play it without changing the speed…but apparently either Apple thinks it should slow down to what Apple decides or it's a bug.

-I'll try recording one in MP4 instead and see what happens…although the default app for those is also QT Player so I would imagine that would slow down just like the MOV does. Converting the MOV into M4V. I'll give Filmora a try if I decide to buy anything more powerful. Converting it to MP4 with VLC Player results in a file that displays the same issues in QT Player but works fine in VLC Player. Pulling that file into iMovie and doing the Revert Speed thing results in video that plays properly but has lost the sound.

So…I've at least got a workaround to do what I wanted to do in the first place…produce slo mo as needed. iMovie has sufficient capabilities to split a long clip that starts at normal speed then shifts to a slowed down portion with a fade from normal to slow then a fade back to normal when desired…although this would then hose the sound so I would have to either have a silent movie or just add a sound track of some sort.

I know there are potential heat and battery life issues with the Z8…but I'm setting it and my Z9 up as identically as possible and don't really envision any long videos anyway… anything more than a couple of minutes is going to be too long for people to watch anyway. I'll try to do most of the recording with my Z9 anyway but it's really going to depend on whether it or the Z8 has the better reach lens for a particular video. I'm taking my 600PF, 100-400, and 24-120…and if my 180-600 arrives before the end of the month it will probably replace the 100-400. My guess is that the 600 will be on the TC most of the time which is perfectly fine and to me the lighter 100-400 seems to make overall balance better on the Z9 as then the body/lens combos are closer to the same weight.

Thanks all for the suggestions.

 

[Nimi]

I'm going to just answer all comments in one reply instead of several. Short answer…I figured out how to solve the problem and it appears to be an obscure Apple bug which I'll report to them for possible fixing.

Thanks for all the good wishes on the trip…and fate willing and with Steve's and the guide's help I'm sure we'll have a fab time.

-Turning on the video early doesn't help to solve my actual desire which is to have a 120 FPS movie that I can use as is or slow down as needed and then output a 30FPS file for the blog or whatever.

-I will probably eventually shift to either Final Cut Pro or DaVinci if I decide I need the more advanced capabilities; but at this point I'm going to stick with iMovie as it does what I want to do. I did download and try DaVinci free version…and the extra unneeded capabilities at this point just make it more cumbersome to use.

-I did more testing today and here's what happens…and it doesn't matter whether the movie format is 8 or 10 bit. Recored at 4K120 and then moved to my MBP running Sonoma…QuickView in Finder displays the video correctly most but not all of the time. Opening in QT Player…which I realize is just a player…always results in 15 or so seconds of normal speed then it slows down to half speed. Pulling the downloaded movie file into iMovie and then dragging to the timeline then clicking on Preview does the same thing within iMovie and exporting results in a file that does the same in QT Player as the original file. Undaunted by this…I installed DaVinci and dragging the movie into it…previewing the file it plays properly and also the exported from there version plays properly. So…knowing I had a solution if I needed it I went back into iMovie and noticed that in the menu where you select slo mo or fast forward there is also a Reset Speed command which was grayed out. So I selected the clip, set it to half speed, then selected the Revert Speed menu item. At that point…the file previews in iMovie just fine and the exported version at 30FPS works just fine as well. More testing revealed that selecting 2X fast forward and then Revert Speed has the same results so the output file plays as expected. So…round about way of solving the problem…but it works.

-I'm not sure why QT slows down playback on its own…seems to me. that if you feed it a file it ought to honor the file contents and play it without changing the speed…but apparently either Apple thinks it should slow down to what Apple decides or it's a bug.

-I'll try recording one in MP4 instead and see what happens…although the default app for those is also QT Player so I would imagine that would slow down just like the MOV does. Converting the MOV into M4V. I'll give Filmora a try if I decide to buy anything more powerful. Converting it to MP4 with VLC Player results in a file that displays the same issues in QT Player but works fine in VLC Player. Pulling that file into iMovie and doing the Revert Speed thing results in video that plays properly but has lost the sound.

So…I've at least got a workaround to do what I wanted to do in the first place…produce slo mo as needed. iMovie has sufficient capabilities to split a long clip that starts at normal speed then shifts to a slowed down portion with a fade from normal to slow then a fade back to normal when desired…although this would then hose the sound so I would have to either have a silent movie or just add a sound track of some sort.

I know there are potential heat and battery life issues with the Z8…but I'm setting it and my Z9 up as identically as possible and don't really envision any long videos anyway… anything more than a couple of minutes is going to be too long for people to watch anyway. I'll try to do most of the recording with my Z9 anyway but it's really going to depend on whether it or the Z8 has the better reach lens for a particular video. I'm taking my 600PF, 100-400, and 24-120…and if my 180-600 arrives before the end of the month it will probably replace the 100-400. My guess is that the 600 will be on the TC most of the time which is perfectly fine and to me the lighter 100-400 seems to make overall balance better on the Z9 as then the body/lens combos are closer to the same weight.

Thanks all for the suggestions.

There is another "bug" In QT Apple calls a feature and you might run into it or a recipient not using QT might run into. If your exported footage is darker, less contrasty and less vivid than you remembered it to be, you need a plugin called Gamma Correction which Adobe and many others provide.

 

[realspeed]

Personally I would not even consider trying to do videos with a camera , too many problems such as over heating - having to change lenses etc etc. To me a camera is for stills and a camcorder is for videos, each is designed for a specific job. Therefore I only use my Nikon D810 for stills and my Panasonic HC-X1500 for videos. Packing a small camcorder into a camera bag instead of some huge heavy "X"mm lens to me makes more sense. I think there is still some taboo people have about camcorders yet they are nowhere near like the old tape movie era of yester year.
I can think of nothing worst then seeing a chance for a video clip/sill only to find the camera has the wrong lens on it and miss that opportunity.

Example a Nikon AF-S 600mm f4E FL ED VR in the UK costs new just about £11,000 pounds . And what can it do ? only take a photo at a distance, and that is all.

My Panasonic HC-X1500 camcorder can do the same 600mm length for £1400 and also close up video/stills as well . On top of that no overheating worries/ no need for lens change and just grab and get that still/video the camera missed. It will go on until the battery runs out or the 2x SD memory cards fill up. this is not even touching sound quality.

river in Iceland (unedited) steady zoom in focus all the way and back, no need for lens change and actual sound as shot
Handheld

https://flic.kr/p/2pCxpg9

Panasonic HV-X1500 camcorder with an Azden SMX-30v microphone

try doing that with a camera using a video setting!!!!!

 

[Calson]

Why do the pro photographers use special zoom lenses instead of a built-in zoom on a camcorder? Your camcorder has a 1/2.5 inch 8.29MP sensor so that is a limitation that will be with every clip shot.

For zoom lenses on the Z cameras there are many choices including the Sigma 60-600mm using a FTZ adapter, the 70-200mm, 100-400mm, and the 180-600mm, at this point in time.

I bought a Sony FDRAX700 4K 14MP 1" sensor camcorder last year but it was to take advantage of its IR night vision capabilities for photographing bats and owls in the "dark" with an IR LED light source. For daylight shooting the Z9 is my choice even if I need to record to internal media.

 

[realspeed]

Why do the pro photographers use special zoom lenses instead of a built-in zoom on a camcorder? Your camcorder has a 1/2.5 inch 8.29MP sensor so that is a limitation that will be with every clip shot.

For zoom lenses on the Z cameras there are many choices including the Sigma 60-600mm using a FTZ adapter, the 70-200mm, 100-400mm, and the 180-600mm, at this point in time.

I bought a Sony FDRAX700 4K 14MP 1" sensor camcorder last year but it was to take advantage of its IR night vision capabilities for photographing bats and owls in the "dark" with an IR LED light source. For daylight shooting the Z9 is my choice even if I need to record to internal media.

One thing you overlooked is cost and also being on an old age pension. you also say "PRO PHOTOGRAPHERS", well many of us are just hobby photographers and not earning from photography.
On this basis one could say why not own a Rolls Royce or Bentley instead of an everyday Ford? the answer is cost.
Quoting what is available out there and what one can afford is a completely stupid arguement

 

[Calson]

Pro photographers I have known if not on a National Geographic crew, need to be very frugal and spend as little as possible on their equipment. I have known many more doctors who bought the latest and greatest camera with no expense spared. Think of the many photographers that go to Africa each year and are spending more than $10,000 for their short trip and double that for a couple and that does not include the cost of their photo gear. Same applies to those on cruise ships.

The biggest difference with the pro wildlife shooter is having a great deal more time to be on site and become comfortable with the wildlife and vice versa. Most hobbyists have less time with travel trips to come back with the images they covet. If the non-pro fails completely for any reason they will still have income and can pay the rent or the mortgage with no worries.

If someone has a tight budget they will buy a used DSLR and not invest in a camcorder that may be OK for videos but not for more than wallet size prints.

 

[PhilcTx]

There is another "bug" In QT Apple calls a feature and you might run into it or a recipient not using QT might run into. If your exported footage is darker, less contrasty and less vivid than you remembered it to be, you need a plugin called Gamma Correction which Adobe and many others provide.

Not sure if this is same thing - but exporting with Rec-709-A instead of Rec-709 could help.:

Davinci Resolve Export Color Different Or Gamma Shift- 3 Fixes

Hey, what’s up guys, welcome back to FilmmakingElements.com. Now, this article is gonna be a lifesaver for so many of you. We cover why there is a color difference or gamma shift or export looks washed out in Davinci Resolve after exporting the video and how it can be fixed. After doing some...

filmmakingelements.com

"Now, what does the Rec.709-A setting doing? Rec.709-A is actually compensating for the gamma difference in the apple devices to that of the standard 2.4 gamma.

Using Apple-based programs and devices such as MacBooks, iPhones, and QuickTime players, then you’ll be pleased to know that there’s a method to ensure perfect color accuracy. By using this method, you can ensure that your colors match perfectly across different Apple devices and programs."

 

[Nimi]

Not sure if this is same thing - but exporting with Rec-709-A instead of Rec-709 could help.:

Davinci Resolve Export Color Different Or Gamma Shift- 3 Fixes

Hey, what’s up guys, welcome back to FilmmakingElements.com. Now, this article is gonna be a lifesaver for so many of you. We cover why there is a color difference or gamma shift or export looks washed out in Davinci Resolve after exporting the video and how it can be fixed. After doing some...

filmmakingelements.com

"Now, what does the Rec.709-A setting doing? Rec.709-A is actually compensating for the gamma difference in the apple devices to that of the standard 2.4 gamma.

Using Apple-based programs and devices such as MacBooks, iPhones, and QuickTime players, then you’ll be pleased to know that there’s a method to ensure perfect color accuracy. By using this method, you can ensure that your colors match perfectly across different Apple devices and programs."

Yes, it's the same as the gamma correction curve Adobe provides. This is the DVR version.

 

[abc123brian]

If using QuickTime to play back and wanting to see it all in slow motion, you will notice a little line on the playback progress bar a few seconds in where the slow motion begins and another towards the end where it returns back to regular speed. You can drag those bars to the beginning, end, or wherever you want to go from regular speed to slow motion. when you close it, it will ask you to save or delete, you can select delete to not save. It just deletes the changes you just made and not the clip itself. As far as I know preview only plays regular speed but I’m probably wrong and there is likely a hidden trick to slow it down.