4K30 vs 4K60

[AKA_Goodfella]

I have been shooting my main footage at 4K30 with a shutter speed of 1/60.
When I want to do Slow Motion, I shoot at 4K60 with a shutter speed of 1/120 and in post I slow the clip down at 40%.

So in the field I am constantly switching between these settings (if only we had programmable buttons) Now I was wondering about the following.

Is shooting at 4K60 with a shutter speed of 1/120 and slowing down in post to 50% basically the same as 4K30 at 1/60?
If so then I could basically shoot everything at 4K60 and wouldn't have to keep switching anymore.

 

[Kilrah]

and slowing down in post to 50%

No, you'd have video playing at half speed.
But if you do nothing and work on/export a 4K30 timeline your video editor will drop half the frames on its own.

All that's left is a faster shutter speed but unless your subject is very specific such as highly dynamic / fast and close to things or filming something that's spinning you won't see the difference.

 

[jephoto]

No, you'd have video playing at half speed.
But if you do nothing and work on/export a 4K30 timeline your video editor will drop half the frames on its own.

All that's left is a faster shutter speed but unless your subject is very specific such as highly dynamic / fast and close to things or filming something that's spinning you won't see the difference.

So, are you saying you can shoot 4k/60 and incorporate it into a timeline with 30 FPS and visually, we won’t be able to tell the difference in the output because the editor drops out every other frame?
I have a client for school websites that nowadays just wants 1080 P/30 fps but occasionally because it’s so bright out I would like to have a faster shutter speed i.e. 1 /120,
But I know they might be adding my footage to other footage shot at 30 FPS.

 

[Kilrah]

Yep, editors conform everything to what you set as timeline size/framerate.
Nothing prevents you from shooting 1/120 at 30fps either.
Just try and experiment a bit.

 

[BobaFut]

So, are you saying you can shoot 4k/60 and incorporate it into a timeline with 30 FPS and visually, we won’t be able to tell the difference in the output because the editor drops out every other frame?
I have a client for school websites that nowadays just wants 1080 P/30 fps but occasionally because it’s so bright out I would like to have a faster shutter speed i.e. 1 /120,
But I know they might be adding my footage to other footage shot at 30 FPS.

You might consider using an ND rather than upping the shutter speed, particularly if you'll be mixing such footage with other footage, just because it might look kinda funny. The 30fps/125s footage (86.4-degree shutter angle) will look extremely sharp and so might stand out with 30fps/60s (180-degree shutter angle) that will have more natural-looking motion blur. But as others have said that won't affect your editing timeline or anything, it's just the visual characteristics of the footage will be noticeably different.

 

[jephoto]

You might consider using an ND rather than upping the shutter speed, particularly if you'll be mixing such footage with other footage, just because it might look kinda funny. The 30fps/125s footage (86.4-degree shutter angle) will look extremely sharp and so might stand out with 30fps/60s (180-degree shutter angle) that will have more natural-looking motion blur. But as others have said that won't affect your editing timeline or anything, it's just the visual characteristics of the footage will be noticeably different.

Oh I do use ND's. Almost every time- unless its dusk or dawn.
But now that I have the M3Pro, even though the main lens has aputures F2.8 -11, the 3x lens is fixed ƒ2.8. If still were all I shot, no prob. Just up the shutter speed. But for video if I want it to look smooth & natural we have no choice but to use ND's.
Right now my choice for a sunny day is the ND 32 which gives me 1/60sec @ ƒ4 on the 1x and ƒ2.8 @200 iso on the 3x lens - if I want to keep settings and exposure as close as possible. And setting the 3x @ 200 give me some wiggle room to go darker (100iso) if need be.
Worked well for me this last week on 3 different jobs.