Video very blurry/jittery on pans at DVinfo.net

Kellen Dengler · December 12th, 2007, 11:28 PM

Hi everyone,

I shot some SD 16x9 video this morning as a test to see how the light would be that time of day. I'm just now sitting down to import the footage and take a look at it.

Every time I had panned or moved the camera in the slightest it's as if there was a delay in the video or some sort of jitter or something that was not there when I shot. I used my 501 Manfrotto sticks and made very smooth motions so I don't understand what happened.

Could I have had some sort of setting on or off I didn't know about? I checked the shutter speed it was at 1/24 which i thought would be fine for normal DV...

Austin Dickson · December 12th, 2007, 11:38 PM

Most likely you have Noise Reduction on. Its can be turned off for your preset in the menu, Customize>Custom Preset>Edit>Select CP>NR1>Off

Also try a faster shutter speed (1/48 at least) but that is probably not the problem.

Kellen Dengler · December 12th, 2007, 11:58 PM

Thanks for the quick reply. So I just checked it out and the noise reduction was off, or at least it is now, but I didn't mess with that at all today. I was shooting using the DVX100 Custom Preset. I upped the shutter speed to 1/48 and I'm noticing that it looks better on the viewfinder.

I guess I was confused thinking 1/24 would be 24 fps? Or is that right? If so, How come there is no 1/30 then? I just assumed that for SD video it would either be 24fps or 30fps...

What is the "standard" shutter speed for SD video? For HDV?

Jimmy Moss · December 13th, 2007, 12:45 AM

Generally you want to use at least double what the frame rate is. So 24fps = 1/48 shutter.

I'm not sure about the DV setting, I never use it, but I noticed that when I shoot 24F at 1/48 shutter and then watch it in FCP full screen on one of my 24 inch dell LCD's fast motion is blurred. If I watch it on a TV or watch the video in a smaller window on my screen it is not there. I'm guessing this is becasue the response time on the 24 inch dell monitors is 16ms (I think) so you get blur or ghosting.

Try a different monitor and see what it looks like.

Jimmy

Kellen Dengler · December 13th, 2007, 01:10 AM

Thanks Jimmy I think this was a shutter thing more than a monitor thing, because I tried looking at it on a tiny window, larger on my MacBook, and full on my iMac and it does get blurrier the bigger, but not much.

Is there a way to fix your shutter speed so as to not accidentally change it while filming? It's entirely possible that I did that because the blur changes consistency throughout the video.

I think I just screwed up my settings somehow and didn't notice with the wrong shutter speed. My girlfriend has one of the huge apple monitors that I get to borrow soon so I'm really going to test some things out with the larger monitor perspective.

Petri Kaipiainen · December 13th, 2007, 03:58 AM

Shooting 24p also makes much more jittery image than standard TV 60i. I really do not understand this craze about slow framerate progressive shooting. On TV interlaced 60i looks better.

Do the same tests with 60i and 1/60 shutter...

Don Palomaki · December 13th, 2007, 07:46 AM

The "delay in the video" and "jitter" you speak of sounds like the lag and overshoot artifacts that can be introduced by image stabilization (IS). Normally IS should be turned off when using a good tripod to avoid these artifacts in pans and tilts. That they happen on only in camera moves reinforces the likelihood that it is IS-related.

If IS is not the issue, keep in mind the pan/tilt and fast motion artifacts you see in film (in part due to the slower frame rate). Film shooters avoid the artifacts (when not wanted) it by not using the rapid camera moves and subjects that will cause them. But they usually are not an issue for 60i video.

Kellen Dengler · December 13th, 2007, 10:10 AM

Thanks I didn't even think about messing with the IS. I'm going to experiment with the shutter speeds and IS and watch it all on a larger monitor to kind of get a full scope as to what makes it do what.

Don Palomaki · December 13th, 2007, 12:01 PM

The IS lag happens because it takes a bit of time for the IS system to figure out that the motion it senses is the start/end of a pan/tilt or intended camera move rather than an unintended camera shake. It cancels the start of the move, than has to catch-up, causing the lag and overshoot, and sometimes some judder mid movement.

December 12th, 2007, 11:28 PM	#1
Kellen Dengler Regular Crew Join Date: Nov 2007 Location: New York, NY Posts: 118	Video very blurry/jittery on pans Hi everyone, I shot some SD 16x9 video this morning as a test to see how the light would be that time of day. I'm just now sitting down to import the footage and take a look at it. Every time I had panned or moved the camera in the slightest it's as if there was a delay in the video or some sort of jitter or something that was not there when I shot. I used my 501 Manfrotto sticks and made very smooth motions so I don't understand what happened. Could I have had some sort of setting on or off I didn't know about? I checked the shutter speed it was at 1/24 which i thought would be fine for normal DV...

December 13th, 2007, 07:46 AM	#7
Don Palomaki Wrangler Join Date: Sep 2001 Location: Northern VA Posts: 4,488	The "delay in the video" and "jitter" you speak of sounds like the lag and overshoot artifacts that can be introduced by image stabilization (IS). Normally IS should be turned off when using a good tripod to avoid these artifacts in pans and tilts. That they happen on only in camera moves reinforces the likelihood that it is IS-related. If IS is not the issue, keep in mind the pan/tilt and fast motion artifacts you see in film (in part due to the slower frame rate). Film shooters avoid the artifacts (when not wanted) it by not using the rapid camera moves and subjects that will cause them. But they usually are not an issue for 60i video. __________________ dpalomaki@dspalomaki.com

December 13th, 2007, 12:01 PM	#9
Don Palomaki Wrangler Join Date: Sep 2001 Location: Northern VA Posts: 4,488	The IS lag happens because it takes a bit of time for the IS system to figure out that the motion it senses is the start/end of a pan/tilt or intended camera move rather than an unintended camera shake. It cancels the start of the move, than has to catch-up, causing the lag and overshoot, and sometimes some judder mid movement. __________________ dpalomaki@dspalomaki.com

December 12th, 2007, 11:38 PM	#2
Austin Dickson New Boot Join Date: Sep 2007 Location: Seattle WA Posts: 19	Most likely you have Noise Reduction on. Its can be turned off for your preset in the menu, Customize>Custom Preset>Edit>Select CP>NR1>Off Also try a faster shutter speed (1/48 at least) but that is probably not the problem.

December 12th, 2007, 11:58 PM	#3
Kellen Dengler Regular Crew Join Date: Nov 2007 Location: New York, NY Posts: 118	Thanks for the quick reply. So I just checked it out and the noise reduction was off, or at least it is now, but I didn't mess with that at all today. I was shooting using the DVX100 Custom Preset. I upped the shutter speed to 1/48 and I'm noticing that it looks better on the viewfinder. I guess I was confused thinking 1/24 would be 24 fps? Or is that right? If so, How come there is no 1/30 then? I just assumed that for SD video it would either be 24fps or 30fps... What is the "standard" shutter speed for SD video? For HDV?

December 13th, 2007, 12:45 AM	#4
Jimmy Moss Regular Crew Join Date: Nov 2007 Location: Nashville TN Posts: 48	Generally you want to use at least double what the frame rate is. So 24fps = 1/48 shutter. I'm not sure about the DV setting, I never use it, but I noticed that when I shoot 24F at 1/48 shutter and then watch it in FCP full screen on one of my 24 inch dell LCD's fast motion is blurred. If I watch it on a TV or watch the video in a smaller window on my screen it is not there. I'm guessing this is becasue the response time on the 24 inch dell monitors is 16ms (I think) so you get blur or ghosting. Try a different monitor and see what it looks like. Jimmy

December 13th, 2007, 01:10 AM	#5
Kellen Dengler Regular Crew Join Date: Nov 2007 Location: New York, NY Posts: 118	Thanks Jimmy I think this was a shutter thing more than a monitor thing, because I tried looking at it on a tiny window, larger on my MacBook, and full on my iMac and it does get blurrier the bigger, but not much. Is there a way to fix your shutter speed so as to not accidentally change it while filming? It's entirely possible that I did that because the blur changes consistency throughout the video. I think I just screwed up my settings somehow and didn't notice with the wrong shutter speed. My girlfriend has one of the huge apple monitors that I get to borrow soon so I'm really going to test some things out with the larger monitor perspective.

December 13th, 2007, 03:58 AM	#6
Petri Kaipiainen Major Player Join Date: Apr 2007 Location: Espoo Finland Posts: 380	Shooting 24p also makes much more jittery image than standard TV 60i. I really do not understand this craze about slow framerate progressive shooting. On TV interlaced 60i looks better. Do the same tests with 60i and 1/60 shutter...

December 13th, 2007, 10:10 AM	#8
Kellen Dengler Regular Crew Join Date: Nov 2007 Location: New York, NY Posts: 118	Thanks I didn't even think about messing with the IS. I'm going to experiment with the shutter speeds and IS and watch it all on a larger monitor to kind of get a full scope as to what makes it do what.