EX1 - Slow Shutter - Motion Blur With No Refresh Stutter? at DVinfo.net

Jonathan Bland · May 25th, 2010, 10:32 AM

Hello Folks,

I'm experimenting with a slow shutter on the EX1.

I would like to know if anyone has been able to achieve a look where, for example, you have crowds of people passing in front of the camera and the people are completely blurred without any delay in movement.

With a slow shutter speed of let's say 8, if I understand correctly, the camera is refreshing once ever 8 frames while 7 frames remain static. This is not creating a smooth flow of movement but rather a jerky flow.

I would like to find a way to 'knock out these 7 frames in camera (but I don't believe this is not possible).... so I've been doing it in post... a hugely tedious process.

Anyone have any ideas on how to maximize the blur movement flow of people without the jerky refreshing rate?

Big thanks :)

Steve Phillipps · May 25th, 2010, 11:52 AM

Remember that your frame rate is dictated by your shutter speed, in that if you have a shutter speed of 1/8 second then obviously the maximum frame rate you can have will be 8 frames per second.
At a shutter speed of 1/8, no there are no "static frames", it's a whole frame at 1/8 second.
Steve

Warren Kawamoto · May 25th, 2010, 01:20 PM

What you're describing is best done in post. With Edius 5.5, add motion blur and you'll get exactly what you want in real time, no rendering necessary.

Omar Idris · May 25th, 2010, 02:09 PM

The trick would be to use interval recording in conjunction with frame accumulation to skip the redundant frames.

Divide your shutter speed by your frame rate and set the interval record to that number or as close as you can get to it. This works best for shutter speeds greater than your frame rate (32 and 64).

For example if your frame rate is 30 and shutter speed is 64, set the interval record to 2 seconds.

I'm assuming you work in progressive. I'm yet to test it with interlaced footage.

Serena Steuart · May 26th, 2010, 05:58 AM

setting EX slow shutter to 16 frames with interval set to 1 sec with 3 frames taken gives a nice effect without excessive time acceleration.

Andy Shipsides · May 26th, 2010, 08:15 AM

I wrote up a blog about time lapse shooting awhile back. I made a video combining slow shutter and time lapse. See my blog here -http://blog.abelcine.com/2009/06/24/time-lapse-recording/

Jonathan Bland · May 26th, 2010, 04:30 PM

Hi Folks,

Big thanks to all of your for the replies.

Again just to touch on the main point....... I'm only interested in achieving a look where all movement is blurred and flows without the intermittent stop/ start of time lapse.

I think it would be something like a 360 degree shutter... or no shutter at all.

Serena.... I'll give your suggestion a shot. Thanks for that.

Sverker Hahn · May 27th, 2010, 07:48 AM

Jonathan, you want the same effect as I thought I could get when I saw "slow shutter" on the cameras specifications. I was a little disappointed when I realised that it was only a longer shutter time told in a different way.

May 25th, 2010, 10:32 AM	#1
Jonathan Bland Major Player Join Date: Apr 2008 Location: Way Far Away Posts: 230	EX1 - Slow Shutter - Motion Blur With No Refresh Stutter? Hello Folks, I'm experimenting with a slow shutter on the EX1. I would like to know if anyone has been able to achieve a look where, for example, you have crowds of people passing in front of the camera and the people are completely blurred without any delay in movement. With a slow shutter speed of let's say 8, if I understand correctly, the camera is refreshing once ever 8 frames while 7 frames remain static. This is not creating a smooth flow of movement but rather a jerky flow. I would like to find a way to 'knock out these 7 frames in camera (but I don't believe this is not possible).... so I've been doing it in post... a hugely tedious process. Anyone have any ideas on how to maximize the blur movement flow of people without the jerky refreshing rate? Big thanks :)

May 26th, 2010, 08:15 AM	#6
Andy Shipsides Sponsor: Abel CineTech Join Date: Feb 2009 Location: New York, NY Posts: 361	I wrote up a blog about time lapse shooting awhile back. I made a video combining slow shutter and time lapse. See my blog here -http://blog.abelcine.com/2009/06/24/time-lapse-recording/ __________________ Andy Shipsides -Camera Technology Specialist AbelCineTech, New York - Visit our Blog - http://blog.abelcine.com

May 25th, 2010, 11:52 AM	#2
Steve Phillipps Inner Circle Join Date: Apr 2006 Location: Wales Posts: 2,130	Remember that your frame rate is dictated by your shutter speed, in that if you have a shutter speed of 1/8 second then obviously the maximum frame rate you can have will be 8 frames per second. At a shutter speed of 1/8, no there are no "static frames", it's a whole frame at 1/8 second. Steve

May 25th, 2010, 01:20 PM	#3
Warren Kawamoto Trustee Join Date: Nov 2006 Location: Honolulu, HI Posts: 1,435	What you're describing is best done in post. With Edius 5.5, add motion blur and you'll get exactly what you want in real time, no rendering necessary.

May 25th, 2010, 02:09 PM	#4
Omar Idris Regular Crew Join Date: Mar 2008 Location: Middlesex, UK Posts: 28	The trick would be to use interval recording in conjunction with frame accumulation to skip the redundant frames. Divide your shutter speed by your frame rate and set the interval record to that number or as close as you can get to it. This works best for shutter speeds greater than your frame rate (32 and 64). For example if your frame rate is 30 and shutter speed is 64, set the interval record to 2 seconds. I'm assuming you work in progressive. I'm yet to test it with interlaced footage.

May 26th, 2010, 05:58 AM	#5
Serena Steuart Major Player Join Date: Jun 2006 Location: Studio Alnitak, Melbourne, Victoria, Australia Posts: 640 Images: 3	setting EX slow shutter to 16 frames with interval set to 1 sec with 3 frames taken gives a nice effect without excessive time acceleration.

May 26th, 2010, 04:30 PM	#7
Jonathan Bland Major Player Join Date: Apr 2008 Location: Way Far Away Posts: 230	Hi Folks, Big thanks to all of your for the replies. Again just to touch on the main point....... I'm only interested in achieving a look where all movement is blurred and flows without the intermittent stop/ start of time lapse. I think it would be something like a 360 degree shutter... or no shutter at all. Serena.... I'll give your suggestion a shot. Thanks for that.

May 27th, 2010, 07:48 AM	#8
Sverker Hahn Regular Crew Join Date: Jun 2008 Location: Stockholm, Sweden Posts: 157	Jonathan, you want the same effect as I thought I could get when I saw "slow shutter" on the cameras specifications. I was a little disappointed when I realised that it was only a longer shutter time told in a different way.