Page 1 of 2

Jerky Panning

PostPosted: Sat Mar 16, 2013 12:27 pm
by Yavor Dimitrov
Hi Black Magic!

I just got my shiny new Cinema Camera and have been playing around with it all day. I have stumbled on an odd problem though that I am not sure if it is the camera or the software.

Whenever I pan, the image jutters until the pan is complete. I have tried slow, medium and fast pans and with each, the problem is there. So every time I have a big camera movement, the image jutters.

Is this a known issue? Is there a fix?

The image jutters in both the camera display and the computer after upload. I have tried both ProRes and Raw but I still have the same problem. Any solutions?

Thanks!

Re: Jerky Panning

PostPosted: Sat Mar 16, 2013 12:30 pm
by Tom
Can you post a video showing the problem?

What Tripod are your using?

Are you using a lens with IS, if so, try doing it with IS turned off.

Re: Jerky Panning

PostPosted: Sat Mar 16, 2013 12:36 pm
by Peter Östlund
Yes it is probably due to image stabilizer trying to correct.

Re: Jerky Panning

PostPosted: Sat Mar 16, 2013 12:44 pm
by Yavor Dimitrov
Tom wrote:Can you post a video showing the problem?

What Tripod are your using?

Are you using a lens with IS, if so, try doing it with IS turned off.


Hi Tom. I am using a Miller DS20 Solo Tripod and shooting with a Canon EFS 17-55 USM 2.8.

Thanks for the suggestion. I will try tomorrow (as it is night here) with the IS turned off. Fingers crossed it is a simple as that.

I am uploading a video now to demonstrate. It will take a few hours though.

Re: Jerky Panning

PostPosted: Sat Mar 16, 2013 1:07 pm
by Yavor Dimitrov
Hi all,

Just tried without IS but still have the jutter. It feels like the camera is struggling to process all the info.

Any ideas?

Re: Jerky Panning

PostPosted: Sat Mar 16, 2013 1:17 pm
by Adam Watkins
Are you shooting 24p?

Re: Jerky Panning

PostPosted: Sat Mar 16, 2013 1:18 pm
by Yavor Dimitrov
Adam Watkins wrote:Are you shooting 24p?


No 25f.

Re: Jerky Panning

PostPosted: Sat Mar 16, 2013 1:22 pm
by Adam Watkins
Are you watching on a "PAL" monitor? Or is your monitor set to 60Hz refresh.

Re: Jerky Panning

PostPosted: Sat Mar 16, 2013 1:25 pm
by Yavor Dimitrov
Adam Watkins wrote:Are you watching on a "PAL" monitor? Or is your monitor set to 60Hz refresh.


I am using a standard computer monitor and have tried 50Hz, 60HZ and even 120Hz but no difference. Even on the camera monitor it jutters.

Re: Jerky Panning

PostPosted: Sat Mar 16, 2013 1:33 pm
by Yavor Dimitrov
I have just noticed another person with the same problem:



At 43 seconds. See how the stones jutter until he stops panning? Is this a widespread issue with the camera?

Re: Jerky Panning

PostPosted: Sat Mar 16, 2013 3:20 pm
by Christian Schmeer
I have the same issue. I thought it might be a software issue, but maybe it's not? It's especially visible in highlights (e.g. windows). I will post an example soon.

Re: Jerky Panning

PostPosted: Sat Mar 16, 2013 3:26 pm
by Yavor Dimitrov
The whole image jerks until the pan or tilt has completed. Here is my example. If you wait for the pan and then observe the movement, you can see it jerking:

I have a 5 year old HDV camera that shoots 25p and it is as smooth as ever. This isn't motion blur but something else. Black Magic could you please comment so we know what to do?

There must be a solution to this? I don't believe that so many people own the camera and haven't noticed such a huge problem.

Re: Jerky Panning

PostPosted: Sat Mar 16, 2013 3:35 pm
by Felix Steinhardt
Have you gone through a pan frame by frame? Is there anything odd?
You should take your scene and make a 25p standard Video-DVD and play it back on your PAL TV. If an unregular stutter is visible there, it is a problem, but 24, 25p on a 60 hz screen looks always very weird expecially while panning.

Re: Jerky Panning

PostPosted: Sat Mar 16, 2013 3:55 pm
by Xtreemtec
Typical progressive issue.

I see the same issue with my JVC camera. 25 Progressive. you see stutter. 50 interlaced and the problem is almost to gone...

If it would do 50 / 60 progressive you would not see this problem anymore i think.

Re: Jerky Panning

PostPosted: Sat Mar 16, 2013 6:54 pm
by Max Manning
You gonna post a video or just keep telling us theres an issue?

Re: Jerky Panning

PostPosted: Sat Mar 16, 2013 7:05 pm
by Frank Glencairn
Arcane23 wrote:The whole image jerks until the pan or tilt has completed. Here is my example. If you wait for the pan and then observe the movement, you can see it jerking:

I have a 5 year old HDV camera that shoots 25p and it is as smooth as ever. This isn't motion blur but something else. Black Magic could you please comment so we know what to do?

There must be a solution to this? I don't believe that so many people own the camera and haven't noticed such a huge problem.


Your HDV camera does fields, totally different beast.
Watch it on a TV or proper production monitor (running at 50HZ) via SDI out, computer monitors don't count. Most of them run at 60HZ internally, no mater what frequency you set your graphics card to.

The FS100 had a real problem with that, even on TVs, but the BMC? No. The motion is very nice.
Keep in mind that when you pan, an object that travels from one side to the other needs at least 7 seconds, or you are panning too fast.

Re: Jerky Panning

PostPosted: Sat Mar 16, 2013 8:12 pm
by Dillon McEvoy
Sorry for this incredibly simplistic question, but could it be the effect of the rolling shutter we're seeing? Faster telephoto pans always bring it out the most. Just a thought

Re: Jerky Panning

PostPosted: Sat Mar 16, 2013 9:01 pm
by Peter Östlund
I have watched the panning now at the link. It is simply not a good panning. To fast.

Re: Jerky Panning

PostPosted: Sat Mar 16, 2013 10:11 pm
by Dillon McEvoy
pict wrote:I have watched the panning now at the link. It is simply not a good panning. To fast.


Too fast in regards to what? Rolling shutter?

Re: Jerky Panning

PostPosted: Sat Mar 16, 2013 11:29 pm
by Frank Glencairn
Nothing to do with rolling shutter

Re: Jerky Panning

PostPosted: Sat Mar 16, 2013 11:46 pm
by Michael Phillips
Take a look at the pan speed based on frame rate, shutter speed, and other factors. This is covered in the ASC Manual as well as the Samuelson Hands On Guide. Here is the relevant chapter online. replace 24 with 25...

http://tinyurl.com/a7tc3ph

Michael

Re: Jerky Panning

PostPosted: Sat Mar 16, 2013 11:51 pm
by Yavor Dimitrov
Frank Glencairn wrote:
Arcane23 wrote:The whole image jerks until the pan or tilt has completed. Here is my example. If you wait for the pan and then observe the movement, you can see it jerking:

I have a 5 year old HDV camera that shoots 25p and it is as smooth as ever. This isn't motion blur but something else. Black Magic could you please comment so we know what to do?

There must be a solution to this? I don't believe that so many people own the camera and haven't noticed such a huge problem.


Your HDV camera does fields, totally different beast.
Watch it on a TV or proper production monitor (running at 50HZ) via SDI out, computer monitors don't count. Most of them run at 60HZ internally, no mater what frequency you set your graphics card to.

The FS100 had a real problem with that, even on TVs, but the BMC? No. The motion is very nice.
Keep in mind that when you pan, an object that travels from one side to the other needs at least 7 seconds, or you are panning too fast.


Thank you all for your thoughts. I had a question Frank, does this mean that every progressive camera that shoots 25p is not able to do quicker pans? I have used a fair few cameras, most of them Broadcast though which I know are interlaced and sometimes running at a higher frame rate, but none have given me this issue.

When watching all the different short films and motion pictures I have never seen this issue. Does that mean they shoot them in different speeds depending on how quick the camera movement is? Would the Alexa or Scarlett look the same when shooting 25p?

Re: Jerky Panning

PostPosted: Sat Mar 16, 2013 11:54 pm
by Yavor Dimitrov
MichaelP wrote:Take a look at the pan speed based on frame rate, shutter speed, and other factors. This is covered in the ASC Manual as well as the Samuelson Hands On Guide. Here is the relevant chapter online. replace 24 with 25...

http://tinyurl.com/a7tc3ph

Michael


Thanks Michael. The link only takes me to the books details but I don't see any link to read the chapters. Can you paste in the comments the relevant information please?

Re: Jerky Panning

PostPosted: Sat Mar 16, 2013 11:56 pm
by Yavor Dimitrov
pict wrote:I have watched the panning now at the link. It is simply not a good panning. To fast.


That is an interesting point. The pan looks like a regular speed movement for any film. Does this mean that depending on the speed of a pan, a different frame rate is used?

Re: Jerky Panning

PostPosted: Sat Mar 16, 2013 11:59 pm
by Michael Phillips
Try this link. It's a scan in Google Books, so I can't copy/paste:

http://books.google.com/books?id=YIkEcI ... te&f=false

Michael

Re: Jerky Panning

PostPosted: Sun Mar 17, 2013 12:15 am
by Yavor Dimitrov
MichaelP wrote:Try this link. It's a scan in Google Books, so I can't copy/paste:

http://books.google.com/books?id=YIkEcI ... te&f=false

Michael


Still doesn't work. Just takes me ton the info page about the book and suggests where I can buy it. And it says there's no E-book version of it.

Re: Jerky Panning

PostPosted: Sun Mar 17, 2013 12:44 am
by Michael Phillips
Strange - Attached is a screenshot of the page.

Michael

Re: Jerky Panning

PostPosted: Sun Mar 17, 2013 12:49 am
by Yavor Dimitrov
MichaelP wrote:Strange - Attached is a screenshot of the page.

Michael


You are a legend thank you! I also found these two websites useful:
http://blog.davidesp.com/archives/436
http://www.red.com/tools/panning-speed

First time I have used a non interlaced, progressive camera that doesn't shoot 50fps. Never knew there were rules to panning.

Re: Jerky Panning

PostPosted: Sun Mar 17, 2013 1:29 am
by Antonio Rosiello
Sorry, i speak english but some technical stuffs are too much for me!

to make it simple, you wait 4 to 7 secs to make the move?

Re: Jerky Panning

PostPosted: Sun Mar 17, 2013 1:43 am
by Michael Phillips
It depends on focal length, and if direction of movement in the frame - it is moving with the pan or against, etc. It does take practice to get a feel for it.

Michael

Re: Jerky Panning

PostPosted: Sun Mar 17, 2013 7:27 am
by Yavor Dimitrov
MichaelP wrote:It depends on focal length, and if direction of movement in the frame - it is moving with the pan or against, etc. It does take practice to get a feel for it.

Michael


So does this mean that all film cameras like RED and Alexa (for example) would look identical in regards to judder?

Re: Jerky Panning

PostPosted: Sun Mar 17, 2013 9:29 am
by Peter Östlund
I would say it was the same when we shot on film. The 7 sec rule is good to follow. Sometimes you have to be even slower in order to avoid the jerky effect.

Re: Jerky Panning

PostPosted: Sun Mar 17, 2013 9:47 am
by Yavor Dimitrov
pict wrote:I would say it was the same when we shot on film. The 7 sec rule is good to follow. Sometimes you have to be even slower in order to avoid the jerky effect.


Sorry but I need to reiterate my question as I have a shoot coming up in the next few months and need to figure out if this camera is up for it.

Will the footage look the same on an Alexa or RED Scarlett when shooting 25p?

I have spent a whole day testing the camera today and with any movement I have had there seems to be judder. Even if it is small movements like following a subject as they walk. When following the conventions of different moving film shots, this drastically reduces what I can do with the camera.

Is this normal for 25p cameras like this? Does this mean to get smooth shots I need to be shooting at a higher frame rate like say 48fps?

Re: Jerky Panning

PostPosted: Sun Mar 17, 2013 10:03 am
by Peter Östlund
I would say the Red camera would render the same result. The problem with rolling shutter doesn't come visible with such "slow" movements. If you have set the shutter to narrow a strobing effect can occur. Try open the shutter more. Good luck.

Re: Jerky Panning

PostPosted: Sun Mar 17, 2013 10:05 am
by Peter Östlund
With shutter I mean the sector setting. 180° as default, but you can open it to 360° and get a longer shutter speed.

Re: Jerky Panning

PostPosted: Sun Mar 17, 2013 10:06 am
by Yavor Dimitrov
pict wrote:I would say the Red camera would render the same result. The problem with rolling shutter doesn't come visible with such "slow" movements. If you have set the shutter to narrow a strobing effect can occur. Try open the shutter more. Good luck.


I have tried all settings but keep getting the same jerky shots. This basically means that this camera can only really be used for stationary shots with minor tilt or pan.

Re: Jerky Panning

PostPosted: Sun Mar 17, 2013 10:23 am
by Klaus Erharter
Arcane23 wrote:So does this mean that all film cameras like RED and Alexa (for example) would look identical in regards to judder?


Simple answer: Yes.

Last time I saw it in cinema was in a movie shot with either Red or Alexa.
It wasn´t a pan, it was a train leaving a station. Same problem though.
As it was speeding up, there was a point when the strobe effect started. And it was at a pretty slow speed.

Re: Jerky Panning

PostPosted: Sun Mar 17, 2013 10:29 am
by Peter Östlund
I am sorry you have this experience. I have shot quite a lot with the camera and cannot say at all that I have the same problem. Maybe the problem is somewhere else. Do you have the same jerkyness looking at the footage in the camera? Maybe the disc reader connected to your system is to slow.

Re: Jerky Panning

PostPosted: Sun Mar 17, 2013 11:00 am
by Yavor Dimitrov
pict wrote:I am sorry you have this experience. I have shot quite a lot with the camera and cannot say at all that I have the same problem. Maybe the problem is somewhere else. Do you have the same jerkyness looking at the footage in the camera? Maybe the disc reader connected to your system is to slow.


The judder is indeed visible in the monitor. It cant be the disk read though as I export the H264 files onto my computers SSD and the 70mb file still judders. I have tried it on multiple monitors and same thing albeit slight differences.

The only time it is smooth is when my Samsung TV does its 100hz thing and adds intermediary frames.

Re: Jerky Panning

PostPosted: Sun Mar 17, 2013 11:47 am
by AndreasK
I watched it frame by frame. Everything is fine, it's just way too fast and imho this is not a 180° shutter, what shutter settings did you use?

Re: Jerky Panning

PostPosted: Sun Mar 17, 2013 12:28 pm
by Soeren Mueller
Arcane23 wrote:The only time it is smooth is when my Samsung TV does its 100hz thing and adds intermediary frames.


Yuck! I'm sorry but than any sort of "cinema" camera (also RED and Alexa) isn't really suited for your needs - or at least you'd have to use RED/Alexa for higher framerates.

Just google for high frame rate / 48fps discussion especially recarding "The Hobbit"...

Personally I can't stand it at all as high framerate/interlaced always reminds me of "reality" TV and has absolutely no cinematic quality for me. But I get that there are a bunch of people really sensitive to this "judder" issue...

You will always have this problem with any 24/25p footage! Unless you set your shutter to 1/24th or 1/25th depending on your fps (or I think 360° would be the equivalent degree) - this will give you much more motion blur, perhaps it helps. (but this again will introduce what some people myself included call the "soap opera"/video look)

Re: Jerky Panning

PostPosted: Sun Mar 17, 2013 1:26 pm
by Michael Phillips
This issue has been around since film days and has to do with a combination of frame rate and shutter speed that equates to overall motion resolution. Cinematographers have used tricks over the years to distract the eye from such pan judders by following a moving object at the rate of a pan - the old waiter with a tray walking across the room trick, etc. The higher the shutter speed, the more "truncated" the look such as the war scenes on Saving Private Ryan or the fight scenes in Gladiator. These were used for creative choices. Motion resolution versus image resolution has been a trade-off for years between 1080i or 720p/59.94 (or 50). Interlace offering more slices of time but half the vertical resolution, etc.

HFR (high frame rate) is certainly something that is being explored by filmmakers as mentioned with The Hobbit. I was helping with a Doug Trumbull project where the goal is an aggregated 120fps with 60 in each eye for stereo 3D. Frame rate is a creative choice much like shutter speed and such. Experience will dictate how well a cinematographer can make each one look and is another tool in the palette.

Projection and displays also play their part - a three bladed projector will appear smoother than a two bladed one which is the more common. CRTs with 48 field display will have a strobe like effect in the highlights that is noticeable. So knowing your subject matter, story style, and supporting it accordingly has been the role of the cinematographer.

Michael

Re: Jerky Panning

PostPosted: Sun Mar 17, 2013 2:12 pm
by Yavor Dimitrov
AndreasK wrote:I watched it frame by frame. Everything is fine, it's just way too fast and imho this is not a 180° shutter, what shutter settings did you use?


This example is actually 180. I made sure of it as I noted it down with every shot I took.

Re: Jerky Panning

PostPosted: Sun Mar 17, 2013 2:24 pm
by Yavor Dimitrov
Soeren Mueller wrote:
Arcane23 wrote:The only time it is smooth is when my Samsung TV does its 100hz thing and adds intermediary frames.


Yuck! I'm sorry but than any sort of "cinema" camera (also RED and Alexa) isn't really suited for your needs - or at least you'd have to use RED/Alexa for higher framerates.

Just google for high frame rate / 48fps discussion especially recarding "The Hobbit"...

Personally I can't stand it at all as high framerate/interlaced always reminds me of "reality" TV and has absolutely no cinematic quality for me. But I get that there are a bunch of people really sensitive to this "judder" issue...

You will always have this problem with any 24/25p footage! Unless you set your shutter to 1/24th or 1/25th depending on your fps (or I think 360° would be the equivalent degree) - this will give you much more motion blur, perhaps it helps. (but this again will introduce what some people myself included call the "soap opera"/video look)


Thank you for that information. I am completely aware of the difference between the qualities of a film look and the HFR TV look, though I don't remember seeing such juddering issues in any of the latest short films at the big festivals or film at the cinema, as I am seeing using the BMCC. On my monitor, it judders so much that it distorts a large amount of the image so that it becomes hard to see the characters actions in the frame. I am no big fan of the TV look as well but there must be some compromise between the two.

Re: Jerky Panning

PostPosted: Sun Mar 17, 2013 9:09 pm
by Frank Glencairn
Arcane23 wrote:I have tried all settings but keep getting the same jerky shots. This basically means that this camera can only really be used for stationary shots with minor tilt or pan.


LOL, yeah - that's why every single film in the last 100 years only features stationary shots and minor tilt and pan.

Re: Jerky Panning

PostPosted: Sun Mar 17, 2013 9:55 pm
by AppleseedTV
Is there any answers from Blackmagic professionals? I have the same problem and ready to give up.

Re: Jerky Panning

PostPosted: Sun Mar 17, 2013 11:16 pm
by Yavor Dimitrov
AppleseedTV wrote:Is there any answers from Blackmagic professionals? I have the same problem and ready to give up.


I just want to be clear, I understand that with 25p there will always be a bit of jerkiness, but I have used other 25p cameras and never had SO much jerkiness in the panning movement.

Also, is there a way of getting a quicker shutter without having to switch to 45 degrees? In my tests 45 degrees introduced way to much rolling shutter.

Re: Jerky Panning

PostPosted: Mon Mar 18, 2013 12:48 am
by Michael Phillips
How does it look on objects passing by like cars and such? Try it at different angles to the passing cars and cards of different speeds. Try shots without the camera moving, and then some following the cares and see if there is something going on or not.

Michael

Re: Jerky Panning

PostPosted: Mon Mar 18, 2013 12:51 am
by Yavor Dimitrov
MichaelP wrote:How does it look on objects passing by like cars and such? Try it at different angles to the passing cars and cards of different speeds. Try shots without the camera moving, and then some following the cares and see if there is something going on or not.

Michael


Thanks Michael. I shall try it as soon as I have resolved the jerkiness. So far it makes anything, even things moving with it, jerky or blurred.

Re: Jerky Panning

PostPosted: Mon Mar 18, 2013 1:11 am
by Frank Glencairn
AppleseedTV wrote:Is there any answers from Blackmagic professionals? I have the same problem and ready to give up.


No offense, but the answer is:

The problem is not in the camera, the problem is behind the camera.

In fact, compared to - let's say a Sony FS100/FS700 or even F3/F5 the BMC has a fantastic smooth motion rendering.

A lot of folks come from shooting 30 frames interlaced, which is much more forgiving. A lot of them also shot 60p. 30 and 60 look nice on computer monitors worldwide, since they run mostly on 60HZ internally. TV sets apply some funky smoothing algorithms and insert frames via Voodoo.

Now you left the world of Television and bought a cinema camera.
It's pretty wired to assume, the cinema camera must adjust to your TV shooting habits.
Like it or not, YOU have to learn to adjust to cinema rules. There is no way to cut corners. Learn how to shoot for cinema, like hundreds of DPs have done before.

Frank