Best practice for slo mo? at DVinfo.net

Darren Ruddock · March 2nd, 2009, 09:54 AM

Hi there,

Until recently I thought that filming slo mo was just a case of overcranking to 60 frames in 720 50p. However I noticed (on another forum!) that it has been suggested shooting in 720 25p and using the S&Q motion at 60 frames produces better results plus gives you the benefit of seeing the results in camera.

I was wondering how you guys (wiser than myself) are doing it? Which method is best with regards to workflow and mixing slo mo in with normal footage.

Many thanks!

Joachim Hoge · March 2nd, 2009, 11:42 AM

I always shoot 60fps in 25P outdoor and 50fps 25P indoor.
The reason is that in Europe the electric frequency is 50hz as opposed to the states that have 60hz.
If I shoot 60fps under artificial lighting the image will pulsate as it´s out of sync with the frequency.

I always presumed that if you shoot 60fps in 50P you only slow down the motion 10% or so?
I mean 50fps in 50P is normal speed right?
You need to shoot 25P to get a proper slo-mo effect.
When we shoot actionsport we normally shoot 720 50P to get as smooth sction as possible and when ever we want slo-mo
we switch the camera to 720 25P and crank it to 60fps.

We drop it all into the same timeline and it inter cuts very well.

Darren Ruddock · March 2nd, 2009, 11:53 AM

Joachim,

Many thanks!

Yeah, it would seem that 10 percent is a good argument! Plus I love seeing the action in cam after.

I use Final Cut Pro and it occurred to me that unless you are dropping your slo mo footage in to a 60fps timeline are you going to get the best from it? If your first clip is shot at 50fps then you drop in a 60fps clip then will the slo mo be affected because it is in the wrong kind of sequence setting?

Interesting stuff!

Matt Davis · March 2nd, 2009, 12:17 PM

On a different tack, you may want to look at Alex Gollner's Compressor tests for making slomo - especially interesting if you're not working with interlaced footage:

Final Cut slow motion at various speeds on Vimeo

BTW, Alex also has some free plugins for FCP that do really useful stuff (I couldn't do without alex4d-vignette) - Free FCP Plug-ins

March 2nd, 2009, 09:54 AM	#1
Darren Ruddock Regular Crew Join Date: Sep 2008 Location: Southend, UK Posts: 165	Best practice for slo mo? Hi there, Until recently I thought that filming slo mo was just a case of overcranking to 60 frames in 720 50p. However I noticed (on another forum!) that it has been suggested shooting in 720 25p and using the S&Q motion at 60 frames produces better results plus gives you the benefit of seeing the results in camera. I was wondering how you guys (wiser than myself) are doing it? Which method is best with regards to workflow and mixing slo mo in with normal footage. Many thanks!

March 2nd, 2009, 12:17 PM	#4
Matt Davis Trustee Join Date: Aug 2005 Location: Berkshire, UK Posts: 1,562	On a different tack, you may want to look at Alex Gollner's Compressor tests for making slomo - especially interesting if you're not working with interlaced footage: Final Cut slow motion at various speeds on Vimeo BTW, Alex also has some free plugins for FCP that do really useful stuff (I couldn't do without alex4d-vignette) - Free FCP Plug-ins __________________ Director/Editor - MDMA Ltd: Write, Shoot, Edit, Publish - mattdavis.pro EX1 x2, C100 --> FCPX & PPro6

March 2nd, 2009, 11:42 AM	#2
Joachim Hoge Major Player Join Date: Apr 2005 Location: Oslo, Norway Posts: 402	I always shoot 60fps in 25P outdoor and 50fps 25P indoor. The reason is that in Europe the electric frequency is 50hz as opposed to the states that have 60hz. If I shoot 60fps under artificial lighting the image will pulsate as it´s out of sync with the frequency. I always presumed that if you shoot 60fps in 50P you only slow down the motion 10% or so? I mean 50fps in 50P is normal speed right? You need to shoot 25P to get a proper slo-mo effect. When we shoot actionsport we normally shoot 720 50P to get as smooth sction as possible and when ever we want slo-mo we switch the camera to 720 25P and crank it to 60fps. We drop it all into the same timeline and it inter cuts very well.

March 2nd, 2009, 11:53 AM	#3
Darren Ruddock Regular Crew Join Date: Sep 2008 Location: Southend, UK Posts: 165	Joachim, Many thanks! Yeah, it would seem that 10 percent is a good argument! Plus I love seeing the action in cam after. I use Final Cut Pro and it occurred to me that unless you are dropping your slo mo footage in to a 60fps timeline are you going to get the best from it? If your first clip is shot at 50fps then you drop in a 60fps clip then will the slo mo be affected because it is in the wrong kind of sequence setting? Interesting stuff!