Allister, thank you for that footage.

A couple fo things I would like to note.

A. It was in 25 and not 24p (not much difference but 24p is where my gripe is)

B. The pan was pretty slow and the majority of the image was over 100 feet+.

If you pan at that speed or just slightly quicker , you will see an annoying flicker effect if the image is closer.

The only thing that this test proved (and yes it did prove something valuable) is that pretty much all HD video cameras have the flicker effect.

This is why I refused to believe that 35mm film 24p is the same as video.

Dennis,

For reasons I tried to explain above, all 24p 180° shutter footage with reasonably linear light sensitivity (film, video, whatever) will exhibit the same tendencies, if played back using the same methods. If there is an anomaly, it's highly unlikely it's in the acquisition and much more likely to be in the playback.

So if you shoot film and progressive video at 24p 180° and transfer/dub them to the same method of playback, the will be more or less identical in their depiction of motion.

What do you envision that film does that video does not to decrease the stutter?

There is in fact a significant difference in how different recording systems may cause more motion judder than others, even all else being equal. The edge enhancement used in video cameras can make 24fps acquisition look much more juddery than say 35mm at the same everything including projection. The issue seems to be so significant that the EE can cause perceived negative steps in movement. Please don't ask me to explain this but there's an excellent paper from the BBC which explains this in great detail with lots of maths.
The way to minimise if not avoid this is to turn down edge enhancement in the camera.

You can emulate an increased-exposure-time-look with heavy detail-settings? Well, I can't. ;)

I've only just caught up on this thread (and i've had too much coffee so putting my 2c in) but the whole 24p strobing thing is just that HD cameras have more DOF with parts of the frame in focus with high contrast areas and therefore the strobing is more obvious. Adding detail would also serve to create parts of the frame that have high contrast, hence the 750 comment.

As many people have pointed out this is completely normal and will vary depending on what's being shot. Having long shutter speeds will help but as Eric quite rightly points out, the cameras cannot really produce odd stuttering effects, what they're doing is pretty simple. Unless the EX1 internal timebase is not accurate and wavers around (which i don't believe it to be the case, it would be pretty impossible to technically screw that up anyway)

In the past people are just careful of how they shoot.

However there is the chance that playback is introducing stuttering (as opposed to strobing) which is dependant on each pipeline. Without examples of bad motion it's difficult to tell. In the case of comparing cameras you need to make sure it's like for like. Like Alister shows, same settings (shutter speed and motion) and im pretty sure that you'll see the same effect because that's just physics at work. Doing 60i -> 24p will introduce blurring artifacts which will help (resolution would be less, less detail to see the effect).

I've got stuff with strobing using a wildly spinning steadicam (don't ask!) and i can see that it's because there's too much detail visible and not enough blur, i can add motion blur in post (it's part of a heavy comp so i knew that going in).

So either some physical cameras are broken (unlikely i would have thought) or the playback has problems or we're expecting the impossible?

Perhaps it would be worth just doing some comparisons of shutter speeds and focus (or try to compare shallow DOF with wide). Or take the example footage and add motion blur in post (but that's only part of the solution, throwing the background out of focus is better)

cheers
paul

On my HDW750 you get motion blur but not the stroby motion I saw on the EX1. Still a bit baffled by this, and because of the fair volume of people raising the issue I don't think it can just be disregarded. Maybe it is the monitoring though, I don't know. Thing is on Alister's tests above I siad they look identical, but they are identical in that I see horrible juddery motion on both - they are equally bad! Nothing to do with you Alister, I know you stated quite clearly that they were too fast and it was to show the effect. But I would expect the effect to be blurring but I see juddering! Again, maybe it's just 'cos it's compessed for the web or whatever?
I may get hold of an EX1 again and try to do some motion tests and get them into an edit suite, I really think this is the only way to know, and again urge anyone to take internet discussion onboard but in in no way treat it as gospel!
Steve

Don't forget though Paul, that there is a radical difference in the EX1 to say Sony 750, which is that it has a rolling shutter, and it's a reasonable assumption to make that this may have an effect.
Steve

Sure, but im pretty sure the rolling shutter won't affect the strobing if you're panning left to right because the sensor readout will be in the same place for a given vertical position, so the same distance even if the overall position is different at the top of the frame compared to the bottom. If you're panning up and down violently then you'll get the jello effect and jello effect trumps strobing each time as far as being objectional goes!

I think that we, as a group, need to quantify what the objectional strobing looks like then take a vote as to whether it is a problem or normal. Alisters examples are normal as far as im concerned. But we've had discussion about a JVC and EX providing different results and i would like to see that.

cheers
paul

If you're using a loooong exposure-time it gets blurry and if you use a shrt exposure-time it gets stroby. A general rule. But what's the difference between what you've seen from the ex1 and your hdcam-footage concerning that subject? It would be nice, if you would post a sample-clip from your hdcam doing a similar pan like that from the xdcam-hd/ex example.

Dominik, unfortunately I couldn't post EX1 clips as I don't have an edit system so couldn't convert to mpeg or whatever. Can't post 750 clips either, but there are some on my website, also film and Phantom HD on there, and none of them have stuttered motion. I did shots on the EX1 following flying birds, also scenic pans and tilts up vegetation to birds in background, all with jittery motion. This was evident at 60P, 25P, shutter 180 degree.
Steve

But of course there will be a mixture of strobing and blurring in my test clips. I was using a 1/50th second (180 degree) shutter.

During the pan, while the shutter is open the camera moves a short distance so it captures an image that includes a lot of background that is blurred due to the motion while the car which is reasonably static in the frame is less blurred. Then the shutter is closed for the same period, meanwhile the camera is still moving. When the shutter re opens the camera is pointing in a slightly different direction so the background jumps while the car stays still. The effect is that the background appears to jump while the foreground car does not.

This is completely normal and totally expected from any sensor or medium exposed in this manner. If you have ever been to an IMAX show you'll know just how bad this can look if the pan speed is too fast.

There is nothing wrong with the way the EX1 captures motion. There are thousands of EX1's in daily use, yet there are less than a dozen (very vocal) people claiming that there is some kind of fault. There are even fewer examples of this "problem" being posted as clips. I think what we are seeing is people getting a camera that can shoot true progressive with a level of detail and resolution that really shows up the issues you get with shooting progressive at low frame rates. Then in many cases the material is being viewed on computers or monitors that add further issues and inconsistencies. This is then being viewed by people not used to seeing such images that don't understand the very nature of progressive and whole frame capture by video and film cameras.

Rolling shutter won't add strobing, it can add skew but only with very,very fast pans or very fast motion and even then it's only slight. Take a look at the lamp posts in my test clips, they don't suddenly lean as I pan.

My test footage was shot at 25p to ensure that there were no issues with pull up from 24p which is another stumbling block for many users not used to working with progressive. The difference between 24P and 25P is only 4% and just about impossible to see visually.

If you are going to do any tests I urge you to do side by side, like for like tests. I can make the output from my EX1 look ugly, I can also make it look beautiful. The difference between ugly and beautiful may just be a small difference in the speed of a pan or the focal length of the lens. Unless you do a like for like test how can you be sure that what you are seeing is down to the camera and not the user.

Steve,

Must also figure in that your 750 is 2/3rds so unless you match the aperture then you'll have less DOF which is a major way of hiding the effect in backgrounds. (even then DOF is a factor of lots of things not just sensor size).

Shame you don't have any of the offending footage to view, that would help enormously!

cheers
paul

Fair volume? Hmm.. with only a couple (who don't even own the camera) and out of the thousands who do....

It's not magic, it's only frame rate and shutter speed here.

Just incase anyone thinks my settings are wrong, I am shooting 1080 24p Angle 180 , detail OFF and still getting judder. I put on a soft FX 3 filter yesterday to make it even softer and it still had judder which was shocking.

Post the footage...
It's hard to buy something like this. especially when there's no proof. Not to mention the majority of us use this camera (along with other cameras) professionally.

Alister, Not all people who've seen this effect are not used to "a camera that can shoot true progressive with a level of detail and resolution". I've shot most of 'em, extensively, Varicam, Sony 750, Phantom HD etc. So it's not as if I or some of the others have just come up from a VX1000!
And I don't see it as helpful to say "less than a dozen (very vocal) people" either, very few people have an agenda here, we're just making comments and observations. Very often I've seen threads like this degenerate into insults and patronising posts (usually by those defending a piece of kit they own and have paid good money for).

Steve

But it is just a handful of people saying there is a problem out of the thousands of EX1 users and owners and they are being very vocal about it, not just here but in other forums as well, refusing to believe that there is no problem. Not one single person that claims there is an issue has been able to post a clip showing it, yet EX1 material must be some of the simplest material in the world to get off the camera and convert.

I have posted a clip that as far as I can tell clearly demonstrates that the EX1 handles motion no differently than any other progressive camera. Now it is being suggested that my test is flawed as both cameras exhibit stutter.
The F350 and EX1 are very different cameras and generate progressive images in very different ways yet they both look the same. What does that tell you? It tells me that the images are as they should be. I could repeat the test with my HD100 but why bother when there are some that clearly don't want to believe that the EX1 works as it should.

I don't understand why anyone expects there not to be judder or stutter when you are doing pans while shooting at 24 or 25P with a 1/50th shutter. That judder is why we have been using 50i or 60i for TV broadcasts for the past 40 years.

Yes I like my EX1 and as a user of one since January I am pretty sure I know what it can and can't do. I've shot almost exclusively using 25P and I've sold footage to Discovery HD, Nat Geo, NHK and others and no one has complained about judder or stutter.

I give up on this thread. No point in saying any more.

Nobody of those claiming that there's a judder-problem were able so far to express that in objective measurable technical terms.
The simple question is:
What exactly does the ex1 wrong? How can I measure it?

I think we just need to await some example footage and then start the discussion again. The ideal would be a comparison of a camera that is said to perform correctly and the EX1 in the same situation.

You see i don't really understand what those that have problems are expecting to see. You open the shutter for X amount of time X times a second and the image is according to that.

The only thing i can think of is that stuttering sounds like a playback issue whereas strobing sounds like a recording one.

cheers
paul

I will post something soon. In the mean time, what benefit does it do that I post a clip of what I am seeing if you guys can't see it from your own monitor. If you don't see it on your monitor with your clips, what makes you think that mines will be any different, unless mine is defective.

Long story short, it does not have the same motion blur when panning as a film camera. The judder looks nasty and I have several people that I showed my footage to that pointed it out. People who have never touched a camera with comments like "is that normal"?

I love the image quality of this camera, workflow, the feel, but the rolling shuuter and the flicker effect has to go.

Well Dennis, that pretty much sums up what I think too.
Thing is Alister, when you say "I don't understand why anyone expects there not to be judder or stutter when you are doing pans while shooting at 24 or 25P with a 1/50th shutter", the answer is because you don't see it with other cameras. You see blurring yes (kinda gives you a nostalgic feeling for interlaced really!), but not stuttering. That's the difference that I was pointing out.
Also I think it's a bit odd to say that "EX1 material must be some of the simplest material in the world to get off the camera and convert", after all the reason I can't post it is that I can't get the bloody shots into mpeg or some form that I can post! Unlike many here I don't do my own editing, call me old fashioned but that's not my job, I just shoot the pictures.
I can put images onto my Macbook and convert them to mpeg4 from Panasonic HPX2100, HPX500, Canon XL, even Phantom HD, but couldn't do it from EX1!
Steve

Steve, I can at least make a suggestion to give you the ability to make your files generally viewable.

http://ffmpegX.com/download.html

The above shareware utility can take the EX1 MP4 and encode them to a variety of formats (H264 for example) that you can upload or otherwise view and share.

Thanks Craig, unfortunately I've deleted my test files, didn't think I had any further use for them.
Steve

This I will agree with, IMHO ANY video 24 or 25P is not the same as film - it's a close approximation but the motion still looks different but that's true of all video cameras.

However compared other video cameras I see no difference in the EX1 progressive footage.

Hi All,

Not wishing to add more noise to this already weighty thread, I simply want to suggest the following 'acid' test...

Dominik Seibold posted a few grabs and merged frames a few days ago which were taken from his EX1 on a spinning chair.

My idea is for a similar repeateable test, but instead place a mirror on the chair (or even better a turntable) with a distant point source light - now you can point two or more different cameras at the mirror and hit record to see how motion is rendered by the different hardware as the reflected light source passes across the frame.

I was a little confused why Dominik chose a shutter angle of 11.25° in his test (=1/768 shutter speed !?) but accept that that was his choice for whatever reason.
I have faked a 'normal' 180° motion blur (added crudely in photoshop) on his merged frames and would expect a very similar result to this from any progressive camera...

Anyone have the inclination (and access to a variety of cameras) to do this would help to settle this issue/thread pretty quickly IMO.

Just my 2p ;)

Cheers,
Dave.

I can't remember exactly why I choose that narrow angle. Perhaps I wanted sharper spots, but of course the result with 180° is more important.
For blending pictures together I wrote a little java-app:
http://www.dominik.ws/PictureAverager.jar (just double-click for launching)
and the source-code:
http://www.dominik.ws/PictureAverager.java
It makes an average-picture out of all pictures in a given folder.
It works like this:
1. Choose the folder with the pictures (all java supported formats like png, jpeg, gif,...). Of course they all must have the same dimensions.
2. Choose the output-filename. The output will be saved as 32bit-png.
3. choose whether to normalize the result or to get the true average.
4. press start
It solely uses integer-arithmetic. First it sums all the channelPixels. Then the per channelPixel result is calculated with the formula sum/pictureCount or with normalization turned on 255*sum/maxSum where maxSum is max(max(red pixels), max(green pixels), max(blue pixels)).

Sony EX1 and JVC HD 101 side by side comparison. Slow and fast pan 25p 1/50th second.

http://www.ingenioustv.com/clips/ex1...otion-test.mov

Thank you Alister, they look pretty damn identical to me, even single stepping through it (aside from the rolling shutter obviously)

I don't want to be seen laboring the point but i wouldn't want others reading this thread to assume it was a problem (or at least a general problem with the EX)

cheers
paul

Thanks once again Alister for taking the time to do this. Yet again, they look the same to me (ie both jerky!) certainly neither camera has an obvious "problem" compared to the other.
Out of interest, I'd say "D" was the EX1, just has that less video look to it (a plus point!). Am I right?
Agree with you Paul, I've said the same above more than once, that people should not "assume" there is a problem here, just be aware that some folks have flagged it and bear it in mind when doing your own tests.
Steve

Yes D is the EX1.

I have not used my HD101 for some time and it was certainly interesting to see the two side by side on a big HD monitor.

I will stick my neck out and say that I do think that the picture quality from the EX1 is quite possibly the nicest I've seen from any video camera. Ever!
It's so much more similar to what you get from a DSLR, very smooth and slightly muted, not "electronic-looking" at all. When I had the camera I put in BBC-like flat settings to get the best DR, exported a still into Photoshop and did some basic manipulation to simulate a grade, and the pic looked gorgeous.
Steve

The clipped areas of the jvc are looking very ugly. Is that normal? Also it has less detail, but a lot of that video-style-sharpening at lower frequencies, a narrow dynamic range and a lot of ca.
The ex1 looks like I love it: wide dynamic range, sharp, clear and natural.

Just a warning here from a housekeeping perspective: I have removed some posts from public view that are pretty much just borderline flaming -- pretty soon now I'm going to start locking accounts. Some of you guys really need to knock it off. You know who you are. It's only a matter of time until I kill this thread...

Also worth mentioning that the other problem reported on DVX User mentioned earlier in this thread looks to be confirmed that the operator was shooting with no shutter on!

Can we just conclude that the EX1 performs in progressive mode like any other video camera and that progressive video doesn't quite have the nice motion that film has - then we can move on :)

To be fair on the HD101 it was probably bordering on being over exposed. Lots more quite harsh enhancement from the JVC but then it was running the stock factory setup while the Ex1 was running my preferred profile which has much reduced detail enhancement.

Just an update, I was one of them thinking the EX1 had more judders but I must admit after doing a quick side by side comparison off a Panasonic HVX2000 (not the 200) and the EX1 at 24p that both showed equal amounts of judders. I was shooting cars driving by at about 50 kms and was very happy to see that a much more expensive camera with ccd's as opposed to cmos and rolling shutter showed the same effect.
So yes, you must adapt your shooting techniques to 24p recording. I noticed that if you are to get a static shot of a car going by, it's doesn't look great, but if you precisely pan as the car goes by, what a difference, it felt very cinematic!

After having read these posts and posts and posts about 24p juddery, and how the EX-1 has more judders etc... I just kept saying in my head, don't these people know that you can't shoot 24p the same as 60i or 60p??? When it's all said and done, it would appear that this is the case. I've long known that there are restrictions with the way one shoots 24p vs. the standard 60i (starting out on DVX's you learn this to be the case early on). I have to say too, I know it's maybe a little lame, but there's just something pleasing to me, when I see 24p over 60i. I shoot most everything I can in 24p, and I'm pleased to know that my next camera will be able to perform it so aptly.

Dave

"There is nothing wrong with the way the EX1 captures motion."

I can't think of a better way to conclude this thread.

Thanks Alister,