HELP! Quick 24 questions at DVinfo.net

Bill Weaver · October 27th, 2006, 11:22 PM

Can somebody give me a fast answer to this?

I've noticed a blurring of video when moving even at slow speeds in 24p. Does using a 48 shutter speed help counteract this movement blur? I will be panning across a lot of detail on paintings, and it needs to be relatively readable.

If it doesn't then I may be faced with switching to 1080i to shoot the bulk of the remainder of a shoot.....

If so, are there effective, non-jerky ways to translate 24p footage back to 1080i?

Thanks
BW

Simon Wyndham · October 28th, 2006, 04:00 AM

You need 1/48th shutter, and then a slower pan. If you pan at medium speed you will get judder.

Nate Weaver · October 28th, 2006, 08:51 AM

24 is 24. You can only do things so fast. If it seems wrong or weird, just remember documentary filmmakers have been working with those limitations for decades...it won't degrade your work.

Alister Chapman · October 28th, 2006, 03:03 PM

24 and 25 P creates some interesting effects. Very slow pans and moves work, medium don't, but then fast moves and pans work again. On a really quick pan or move you don't "see" the judder that really stands out in medium speed moves. 1/48th shutter gives less blur, but depending on the move speed can increase stutter. I have also found that the judder seems to look worse in the viewfinder than on a large monitor, don't know why!

Simon Wyndham · October 28th, 2006, 03:14 PM

If you are shooting with your none viewfinder eye open, with your other eye looking at the viewfinder, then the judder will be more noticeable.

A lot of people I speak to are worried about progressive scan, and seem to look upon it as a dark art that you need to be really careful with.

Fact is, when everything is edited together and you are watching things normally on a TV, you won't notice it anywhere near as much.

For example, when you watch 24 do you notice the judder? Its frantic handheld camerawork should make it stand out like a sore thumb. Yet it doesn't.

My advice to anyone shooting progressive scan is not to worry so much, and don't over analyze the footage.

Nigel Cooper · October 28th, 2006, 05:50 PM

Good points Simon.

I was asking my girlfriend the other day to tell me which footage she preferred the look of between some interlaced and some progressive. She said she preferred the progressive as it looked smoother and more film like. Then I asked here if the judder bothered her. She said she had not noticed it until I pointed it out and she then looked for it.

Thierry Humeau · October 29th, 2006, 01:49 PM

Quote:

Originally Posted by Bill Weaver

Can somebody give me a fast answer to this?

I've noticed a blurring of video when moving even at slow speeds in 24p. Does using a 48 shutter speed help counteract this movement blur? I will be panning across a lot of detail on paintings, and it needs to be relatively readable....BW

Bill,

In my experienced, using a 48th/sec. shutter speed does not help at all. You just have to pan either really slow or at a fairly good speed. For the type of art shots you described, I would strongly advise you to shoot in 30p or even 60i. I recently shot a program on Rembrandt for NHK, doing a lot of camera moves accross painting at different speeds and different angles and I am glad we were working at 60i.

If you have an edit system that can ingest video via HD-SDI, you may want, depending on contents, to consider shooting at different frame rates. I am working on a doc now that involves quite a few table shots of different artifacts (shot at 30p or 60i) mixed with stock footage (SD at 30i) and interviews / GVs (shot at 24p). I am editing in an AVID 1080 60i project and use the XDCAM HD deck built-in frame rate conversion feature to ingest everything as 1080 60i HD video. Works great! Unfortunetly, if you want to edit in FAM mode (MXF file transfer), you do not have this flexibility. As of now, it is not possible to change frame rates or to add pulldown when importing XDCAM clips via FAM.

Thierry.

Simon Wyndham · October 29th, 2006, 02:15 PM

Indeed some projects are better in interlaced. High def for me doesn't have the same cheap video look when interlaced that SD does.

But if the director wants 24p, then that must be worked around.

For example, is it absolutely unnecessary to pan across the paintings, or is there another better creative way to do things?

Bill Weaver · October 29th, 2006, 04:14 PM

Here are my discoveries after my initial shoot yesterday with Canadian painter Robert Batemsn:

I'm glad I'm working in 24p, as it gives the piece a more classic look, which is what I am looking for.

I shot using very little detail (20 out of 150)

I found 48 shutter to be mainly a limitation, as it seemed to cause filckering and stobing with backround vegetation and with blades of grass. Most of these shots are too distracting to be used. I'll try to slightly soften ones that are must-have.

I shot rest of day in 24p, no shutter, and everything worked well. It still feels film-like.

I did some test shots with very slow paning across canvases, and all seemed AOK.

BUT -- here's something I can't figure out. In some cases, bright sky shots and other overexposed spots seem to pulse and/or clamp. Any ideas on what might be causing this?

Thanks

Nate Weaver · October 29th, 2006, 04:45 PM

Quote:

Originally Posted by Bill Weaver

BUT -- here's something I can't figure out. In some cases, bright sky shots and other overexposed spots seem to pulse and/or clamp. Any ideas on what might be causing this?

I've had serious iris hunting for the first time with the new firmware, where I'd never had it before. I believe there's an iris response setting in the maintenance menu, I might have a look at that.

Simon Wyndham · October 29th, 2006, 04:48 PM

Detail is important with filmlook. Turning it down is good. Usually I'd turn it off completely with progressive scan.

Quote:

BUT -- here's something I can't figure out. In some cases, bright sky shots and other overexposed spots seem to pulse and/or clamp. Any ideas on what might be causing this?

Did you have the DCC on? The DCC on the XDCAM HD I have found seems to have some pretty bad 'hunting' issues. I had hoped that it would be fixed in the latest firmware.

Bill Weaver · October 29th, 2006, 05:00 PM

Quote:

Originally Posted by Nate Weaver

I've had serious iris hunting for the first time with the new firmware, where I'd never had it before. I believe there's an iris response setting in the maintenance menu, I might have a look at that.

Wasn't using auto iris. It was like the sky started flashing. Never seen this before. Any other ideas?

Quote:

Originally Posted by Simon Wyndham

Did you have the DCC on? The DCC on the XDCAM HD I have found seems to have some pretty bad 'hunting' issues. I had hoped that it would be fixed in the latest firmware.

I'll check on that. Unfortunately, I do not yet have latest firmware.

Simon Wyndham · October 29th, 2006, 05:17 PM

Definitely sounds like the DCC. Can you check whether it was on?

Alister Chapman · October 30th, 2006, 02:41 PM

Did you have zebra on that was just starting to show?

Greg Boston · October 30th, 2006, 03:28 PM

Quote:

Originally Posted by Bill Weaver

I found 48 shutter to be mainly a limitation, as it seemed to cause filckering and stobing with backround vegetation and with blades of grass. Most of these shots are too distracting to be used. I'll try to slightly soften ones that are must-have.

1/48 shutter equates to the 180 degree shutter angle that is standard on motion film cameras. The flickering and strobing of background vegetation and blades of grass during pans are part of the reason shallow DOF is used because it hides that ugly side-effect as you follow the main subject.

You may see 1/48 as a limitation, but it's been standard practice for many years.

Shooting 24p means you have to adapt your technique to that of the way standard motion pictures have been done for years.

-gb-

October 27th, 2006, 11:22 PM	#1
Bill Weaver Regular Crew Join Date: May 2006 Location: Victoria,BC Posts: 124	HELP! Quick 24 questions Can somebody give me a fast answer to this? I've noticed a blurring of video when moving even at slow speeds in 24p. Does using a 48 shutter speed help counteract this movement blur? I will be panning across a lot of detail on paintings, and it needs to be relatively readable. If it doesn't then I may be faced with switching to 1080i to shoot the bulk of the remainder of a shoot..... If so, are there effective, non-jerky ways to translate 24p footage back to 1080i? Thanks BW __________________ Bill Weaver Across Borders Media / Media that Matters

October 28th, 2006, 08:51 AM	#3
Nate Weaver Wrangler Join Date: Oct 2002 Location: Los Angeles, CA Posts: 2,100	24 is 24. You can only do things so fast. If it seems wrong or weird, just remember documentary filmmakers have been working with those limitations for decades...it won't degrade your work. __________________ My Work: nateweaver.net

October 28th, 2006, 03:03 PM	#4
Alister Chapman Inner Circle Join Date: Dec 2005 Location: Bracknell, Berkshire, UK Posts: 4,957	24 and 25 P creates some interesting effects. Very slow pans and moves work, medium don't, but then fast moves and pans work again. On a really quick pan or move you don't "see" the judder that really stands out in medium speed moves. 1/48th shutter gives less blur, but depending on the move speed can increase stutter. I have also found that the judder seems to look worse in the viewfinder than on a large monitor, don't know why! __________________ Alister Chapman, Film-Maker/Stormchaser http://www.xdcam-user.com/alisters-blog/ My XDCAM site and blog. http://www.hurricane-rig.com

October 29th, 2006, 04:14 PM	#9
Bill Weaver Regular Crew Join Date: May 2006 Location: Victoria,BC Posts: 124	Here are my discoveries after my initial shoot yesterday with Canadian painter Robert Batemsn: I'm glad I'm working in 24p, as it gives the piece a more classic look, which is what I am looking for. I shot using very little detail (20 out of 150) I found 48 shutter to be mainly a limitation, as it seemed to cause filckering and stobing with backround vegetation and with blades of grass. Most of these shots are too distracting to be used. I'll try to slightly soften ones that are must-have. I shot rest of day in 24p, no shutter, and everything worked well. It still feels film-like. I did some test shots with very slow paning across canvases, and all seemed AOK. BUT -- here's something I can't figure out. In some cases, bright sky shots and other overexposed spots seem to pulse and/or clamp. Any ideas on what might be causing this? Thanks __________________ Bill Weaver Across Borders Media / Media that Matters

October 30th, 2006, 02:41 PM	#14
Alister Chapman Inner Circle Join Date: Dec 2005 Location: Bracknell, Berkshire, UK Posts: 4,957	Did you have zebra on that was just starting to show? __________________ Alister Chapman, Film-Maker/Stormchaser http://www.xdcam-user.com/alisters-blog/ My XDCAM site and blog. http://www.hurricane-rig.com

October 28th, 2006, 04:00 AM	#2
Simon Wyndham Trustee Join Date: Dec 2003 Location: Malvern UK Posts: 1,931	You need 1/48th shutter, and then a slower pan. If you pan at medium speed you will get judder.

October 28th, 2006, 03:14 PM	#5
Simon Wyndham Trustee Join Date: Dec 2003 Location: Malvern UK Posts: 1,931	If you are shooting with your none viewfinder eye open, with your other eye looking at the viewfinder, then the judder will be more noticeable. A lot of people I speak to are worried about progressive scan, and seem to look upon it as a dark art that you need to be really careful with. Fact is, when everything is edited together and you are watching things normally on a TV, you won't notice it anywhere near as much. For example, when you watch 24 do you notice the judder? Its frantic handheld camerawork should make it stand out like a sore thumb. Yet it doesn't. My advice to anyone shooting progressive scan is not to worry so much, and don't over analyze the footage.

October 28th, 2006, 05:50 PM	#6
Nigel Cooper Major Player Join Date: Feb 2005 Location: Cambridgeshire, UK Posts: 112	Good points Simon. I was asking my girlfriend the other day to tell me which footage she preferred the look of between some interlaced and some progressive. She said she preferred the progressive as it looked smoother and more film like. Then I asked here if the judder bothered her. She said she had not noticed it until I pointed it out and she then looked for it.

October 29th, 2006, 02:15 PM	#8
Simon Wyndham Trustee Join Date: Dec 2003 Location: Malvern UK Posts: 1,931	Indeed some projects are better in interlaced. High def for me doesn't have the same cheap video look when interlaced that SD does. But if the director wants 24p, then that must be worked around. For example, is it absolutely unnecessary to pan across the paintings, or is there another better creative way to do things?

October 29th, 2006, 05:17 PM	#13
Simon Wyndham Trustee Join Date: Dec 2003 Location: Malvern UK Posts: 1,931	Definitely sounds like the DCC. Can you check whether it was on?