1/48 Shutter Speed at DVinfo.net

Todd Clark · March 12th, 2010, 12:00 PM

Is it true the T2i does NOT offer 1/48 shutter speed? I searched and could not find confirmation. I thought that speed would be optimal for 24p.

Jon Fairhurst · March 12th, 2010, 12:27 PM

1/50 will be close enough.

Ed Kishel · March 12th, 2010, 01:01 PM

yes- I doubt anyone could see the difference between 1/50 and 1/48

Jon Fairhurst · March 12th, 2010, 03:22 PM

Regarding shutter speed, close enough is good enough. The most important thing is that it's consistent from shot to shot, so you don't get exposure changes. In my experience, there's no significant variation at all.

Frankly, the biggest problem that I've seen, as far as the electronic shutter giving a video rather than film look, is that there can be a bit of an edge on motion blur. Ideally, the blur would be uniform within any given frame. As I recall, there is a bit of a hard side and a soft side to motion.

I wouldn't lose sleep over it though. This is getting into really subtle stuff. I recommend setting to 1/50 and forgetting about it. The exceptions are where you would want 1/60 (or 1/30) under fluorescents in the US and other 60 Hz countries. Also, feel free to set a faster speed when you want a stutter look. Why dying for more light, go to a slower speed as a last resort, but try to keep any motion slow and controlled.

Jon Fairhurst · March 12th, 2010, 03:28 PM

Here's a new post that shows why one might want a fast shutter speed: for frame grabs:

http://www.dvinfo.net/forum/eos-5d-m...ml#post1498771

It's too bad he didn't contrast the fast shutter with 1/60, since 1/60 is a 180 degree shutter as used in film. I would never use 1/30 in daylight.

David Mullen · March 21st, 2010, 02:54 PM

1/60th is the shutter speed when shooting at 30 fps with a 180 degree shutter. 1/48th is the shutter speed when shooting at 24 fps with a 180 degree shutter.

The difference between 1/48th and 1/50th is negligible.

Jon Fairhurst · March 21st, 2010, 06:03 PM

Adding to David's post, regardless of shooting 24p or 30p, use 1/50 under fluorescent lights in Europe and 50 Hz regions, and 1/60 or 1/30 under US and 60Hz lights.

It's not exactly 180 degrees (1/50 during 30p or 1/60 during 24p), but it's close enough. The strobing with fluorescent lights is objectionable, while a somewhat imperfect 180 degree shutter is no big deal.

Michiel van Baasbank · March 22nd, 2010, 02:46 PM

But, in PAL-country, 25p and 1/50 would correspond with the 180 degree shutter. I think the difference between 25p and 24p would be negligible as well.

For footage to be used in slow-motion, it's generally better to have a high shutter speed as well, isn't it?

Jon Fairhurst · March 22nd, 2010, 04:49 PM

Yes, high shutter if you plan to create slow motion with tweening software - unless you have fast lights that will strobe at faster shutter speeds.

Stan Chase · March 23rd, 2010, 11:30 AM

Quote:

Originally Posted by Michiel van Baasbank

For footage to be used in slow-motion, it's generally better to have a high shutter speed as well, isn't it?

What's the best shutter speed to use for 720p60 if you want to drop it in a 24p timeline for slo-mo?

Jon Fairhurst · March 23rd, 2010, 03:44 PM

I recommend 1/120. The general idea is to keep everything at 180 degrees, or half of the frame rate no matter what you shoot. When you slow it down to 24p, it will have a consistent look, balancing blur and smooth motion.

Just be careful when shooting under lights. 1/120 might strobe. That could force you to use 1/60.

OTOH, if shooting 1080p24/25/30 with the intent of using Twixtor, I recommend using a faster shutter to avoid motion blur. Motion interpolation does best with crisp edges.

March 12th, 2010, 12:00 PM	#1
Todd Clark Regular Crew Join Date: Feb 2007 Location: Parma, Oh Posts: 172	1/48 Shutter Speed Is it true the T2i does NOT offer 1/48 shutter speed? I searched and could not find confirmation. I thought that speed would be optimal for 24p.

March 12th, 2010, 12:27 PM	#2
Jon Fairhurst Inner Circle Join Date: May 2006 Location: Camas, WA, USA Posts: 5,513	1/50 will be close enough. __________________ Jon Fairhurst

March 12th, 2010, 03:22 PM	#4
Jon Fairhurst Inner Circle Join Date: May 2006 Location: Camas, WA, USA Posts: 5,513	Regarding shutter speed, close enough is good enough. The most important thing is that it's consistent from shot to shot, so you don't get exposure changes. In my experience, there's no significant variation at all. Frankly, the biggest problem that I've seen, as far as the electronic shutter giving a video rather than film look, is that there can be a bit of an edge on motion blur. Ideally, the blur would be uniform within any given frame. As I recall, there is a bit of a hard side and a soft side to motion. I wouldn't lose sleep over it though. This is getting into really subtle stuff. I recommend setting to 1/50 and forgetting about it. The exceptions are where you would want 1/60 (or 1/30) under fluorescents in the US and other 60 Hz countries. Also, feel free to set a faster speed when you want a stutter look. Why dying for more light, go to a slower speed as a last resort, but try to keep any motion slow and controlled. __________________ Jon Fairhurst

March 12th, 2010, 03:28 PM	#5
Jon Fairhurst Inner Circle Join Date: May 2006 Location: Camas, WA, USA Posts: 5,513	Here's a new post that shows why one might want a fast shutter speed: for frame grabs: http://www.dvinfo.net/forum/eos-5d-m...ml#post1498771 It's too bad he didn't contrast the fast shutter with 1/60, since 1/60 is a 180 degree shutter as used in film. I would never use 1/30 in daylight. __________________ Jon Fairhurst

March 21st, 2010, 02:54 PM	#6
David Mullen American Society of Cinematographers Join Date: Jan 2003 Location: Los Angeles, CA Posts: 123	1/60th is the shutter speed when shooting at 30 fps with a 180 degree shutter. 1/48th is the shutter speed when shooting at 24 fps with a 180 degree shutter. The difference between 1/48th and 1/50th is negligible. __________________ David Mullen, ASC Los Angeles

March 12th, 2010, 01:01 PM	#3
Ed Kishel Regular Crew Join Date: Apr 2008 Location: Phoenix, AZ Posts: 80	yes- I doubt anyone could see the difference between 1/50 and 1/48

March 21st, 2010, 06:03 PM	#7
Jon Fairhurst Inner Circle Join Date: May 2006 Location: Camas, WA, USA Posts: 5,513	Adding to David's post, regardless of shooting 24p or 30p, use 1/50 under fluorescent lights in Europe and 50 Hz regions, and 1/60 or 1/30 under US and 60Hz lights. It's not exactly 180 degrees (1/50 during 30p or 1/60 during 24p), but it's close enough. The strobing with fluorescent lights is objectionable, while a somewhat imperfect 180 degree shutter is no big deal. __________________ Jon Fairhurst

March 22nd, 2010, 02:46 PM	#8
Michiel van Baasbank Regular Crew Join Date: Jan 2010 Location: the Netherlands Posts: 63	But, in PAL-country, 25p and 1/50 would correspond with the 180 degree shutter. I think the difference between 25p and 24p would be negligible as well. For footage to be used in slow-motion, it's generally better to have a high shutter speed as well, isn't it?

March 22nd, 2010, 04:49 PM	#9
Jon Fairhurst Inner Circle Join Date: May 2006 Location: Camas, WA, USA Posts: 5,513	Yes, high shutter if you plan to create slow motion with tweening software - unless you have fast lights that will strobe at faster shutter speeds. __________________ Jon Fairhurst

March 23rd, 2010, 03:44 PM	#11
Jon Fairhurst Inner Circle Join Date: May 2006 Location: Camas, WA, USA Posts: 5,513	I recommend 1/120. The general idea is to keep everything at 180 degrees, or half of the frame rate no matter what you shoot. When you slow it down to 24p, it will have a consistent look, balancing blur and smooth motion. Just be careful when shooting under lights. 1/120 might strobe. That could force you to use 1/60. OTOH, if shooting 1080p24/25/30 with the intent of using Twixtor, I recommend using a faster shutter to avoid motion blur. Motion interpolation does best with crisp edges. __________________ Jon Fairhurst