Thinking of switching to 30/60fps for some projects

[Nigel Davey]

I'm based in the UK where obviously PAL/25 fps has been the video default for decades. But these days pretty much all of my projects are Net delivered/viewed rather than broadcast. Also quite a lot of them involve a degree of activity and movement where the option of slomo in Post is very useful. Which is why most of my projects are now shot in 50fps but exported in 25fps.

But I've been thinking of shooting in 30/60fps (exporting in 30fps) to give me that extra 16% of slomo.

As a UK shooter am I missing any downsides or potential issues in doing this? I realise Premiere won't be 100% happy to mix 30fps and 25fps (archive) clips on the same timeline, but it would be rare and Optical Flow may help me out here.

[Gary Huff]

Originally Posted by Nigel Davey

I realise Premiere won't be 100% happy to mix 30fps and 25fps (archive) clips on the same timeline, but it would be rare and Optical Flow may help me out here.

That's why you should test beforehand. Optical Flow may make it look even wonkier, and could add a significant amount of time to your render if you have to do it for a ton of clips.

[Nigel Davey]

True Gary. But I've already had to do it with drone footage delivered to me in 30fps and stock clips from the likes of Pond 5 & Videoblocks and thus far you wouldn't spot the difference with Optical flow applied on a 25fps sequence.

[Gary Huff]

No testing needed for clips that you shoot then I guess.

[Nigel Davey]

No need for the sarcasm Gary. Yes of course I would test both FS5 25 and 30fps clips on the same timeline before attempting it in a paid project. But the likelihood of mixing both will be rare since I'm contemplating shooting new projects entirely in 30fps with very occasional use of archive footage.

The reason I originally mentioned mixed frames was to highlight I'm aware of the drawbacks and it's the other unforeseen stuff I'm trying to draw out.

Living in a mostly 25fps world, it feels like a brave step that could easily backfire if I don't think it through.

[Jack Zhang]

The only concern you might run into is a mismatch with some mains driven lighting due to the different mains frequencies. If you shoot mostly outdoors content, the problem is technically non-existent. (except at night, cause the mains frequencies come into play again with city lights)

30fps has in a way become the most common framerate seen in internet video delivery, mostly cause iPhones shoot at 30fps Non drop-frame and only dip down to 24fps when the light is low, and that's a NIGHTMARE for QC of iPhone footage. iPhone video has variable frame rate, so the framerate changes on the fly in the file. Android video capture calculates framerate in fractions! The files they produce never amount to a proper decimal value!

But everything is what it is, 30fps has become common place in terms of web video.

[Gary Huff]

The only way it could potentially bite you is if you ever need to deliver a project in the DVD or
Blu-ray format. Less so for USB delivery. I think any Smart TV or Blu-ray player/console that could play an MP4 off of a USB stick should be able to deal with a 30p stream on a PAL digital display. But there could be issues even still, you just never know what kind of b.s. is still going on with hardware in a mixed format world.

For online streaming delivery, I don't think you'll experience any issues.

[Dave Sperling]

Originally Posted by Nigel Davey

I'm based in the UK where obviously PAL/25 fps has been the video default for decades. But these days pretty much all of my projects are Net delivered/viewed rather than broadcast. Also quite a lot of them involve a degree of activity and movement where the option of slomo in Post is very useful. Which is why most of my projects are now shot in 50fps but exported in 25fps.

But I've been thinking of shooting in 30/60fps (exporting in 30fps) to give me that extra 16% of slomo.

As a UK shooter am I missing any downsides or potential issues in doing this? I realise Premiere won't be 100% happy to mix 30fps and 25fps (archive) clips on the same timeline, but it would be rare and Optical Flow may help me out here.

If I understand you correctly you'd like to get a higher slow motion ratio? But shooting at 60 and outputting at 30 is a 2:1 slow motion, which is the same 2:1 ratio as shooting at 50 and outputting at 25. To gain a higher slow motion ratio you would need to shoot at 60 and output at a lower frame rate - such as 25 or 24... (60/24 = a 2.5 speed ratio)

But of course the best is for you to do some testing and see what works best for your needs...

[Nigel Davey]

Dave you're right and I've been a complete numpty. Somehow I've avoided realising they were proportionate with my head locked in to 25fps rather than the increase to 30.

Thanks also to Gary and Jack, I hadn't considered either of those issues.

I guess there are only two minor gains for me to switch to 30fps, but neither valuable enough to actually do it. Firstly 30p looks smoother than 25, ie less staccato effect. Secondly the proper FS5 slow motion rates will give me that 16% extra slomo if my timeline is set at 25fps. Tell me I got that bit right Dave:-)

[Gary Huff]

Originally Posted by Nigel Davey

Firstly 30p looks smoother than 25, ie less staccato effect.

First, you should be using a 180 degree shutter to alleviate that. If you're shooting over 1/50 (especially significantly over) you'll get that effect. Past that, you can only move the camera so fast at 25 fps. So if you're whipping it around, you'll get that famous judder. It should take you 7 seconds to pan completely through a scene to avoid it.

[Donald McPherson]

I once tried mixing with 25fps from my DSLR and my phone 30fps I couln't get the audio to match. Have not tried again. But if I did it would be both 30fps. even in PAL land most if not all DVD players will accept 30fps NTFS.

[Nigel Davey]

I usually shoot at 1/50 shutter, even if I'm shooting 50fps. I've always understood your shutter speed should be at least double your frame rate. So in theory I should shoot at 1/100 for 50fps. But I normally drop my 50fps clips onto a 25fps sequence in Premiere, whereby Premiere throws away every other frame and you are back to 25p at 1/50 shutter speed.

In all honesty I hate the way 25p looks on the FS5, at least on the default camera monitor. For some reason it looks worse than 25p on my DSLR's. But interestingly by the time it's been through Premiere and exported to Vimetube it looks ok, ie not badly staccato'ed, on a PC screen.

But nonetheless I prefer not to have to look at 25p on the FS5 monitor, which I avoid anyway by shooting 50fps.

It has crossed my mind that it probably doesn't look as staccato'ed on FS5 monitors shooting at 30fps, with those extra 5 frames smoothing things out a bit. Maybe when I get my FS5 back from Sony I'll take a look.

[Jack Zhang]

Originally Posted by Gary Huff

The only way it could potentially bite you is if you ever need to deliver a project in the DVD or Blu-ray format.

You have to worry about DVD more cause region and frequencies matter more.

You'll actually be of advantage for Blu-ray cause there's no support for PAL frame rates for the format entirely. All BBC 1080i50 content has to be converted to 1080i60 to be printed to Blu-ray.

[Gary Huff]

Originally Posted by Jack Zhang

You'll actually be of advantage for Blu-ray cause there's no support for PAL frame rates for the format entirely. All BBC 1080i50 content has to be converted to 1080i60 to be printed to Blu-ray.

Jack, please don't spread misinformation like this. It is not true at all. Blu-ray fully supports 1080i50. It would be ridiculous for it not to. 25p can be embedded in 50i with 2:2 pulldown.