EX1 and flying birds

[Steven Thomas]

Steve, with all due respect, you need to look up the meaning of CMOS rolling shutter issues such as skew, wobble, and partial exposures. You can not rope them all together as whatever "you want to call it."

Each artifact is VISUALLY different and seen under different conditions.

Save your money and buy a CCD camera such as the HVX200. The HVX200 is a decent camera for the money.

[Steve Phillipps]

I think my description has been understood now, and I think the correct term is skew. HVX200 no good to me, I need interchangeable lenses on any cam I use, hence why I was looking towards an EX3. Also HVX not accepted as full HD by BBC (my main client), EX3 with Flash XDR would have just crept in.
HD cams are still evolving so still not the time to spend £50k, so at the moment I'm hiring/using kit owned by productions, but it is nice to have a personal camera (still have a Digibeta and film camera but neither are really that much in demand these days), just nothing sub £10k or so that really ticks all my boxes at present.
Steve

[James Carl]

It was not skew, it was as if there was a cadence issue perhaps. I have been searching high and low for an answer and I was very hopeful finding this thread.
Other pros who saw the footage on a broadcast monitor thought it was a codec limitation issue, at first I thought it was the image stabilizer grabbing hold of the moving parts of the horizon. Whatever it is, it's uneven and it's very annoying during a pan that was suppose to be smooth.

[QUOTE=Steve Phillipps;879485]I think my description has been understood now, and I think the correct term is skew.

Are you sure what you saw was skew? Commonly, skew is the vertical axis of the image slanting during a fast pan due to it being captured milliseconds apart in blocks of rows from the sensor, top to bottom. However any way you move an EX1 too fast, there could be distortion and this is very bad if you are later trying to stabilize your footage as you will get a made out of jello look.

[Steve Phillipps]

No idea if it was "skew", that was just what other folks seemed to be suggesting. I then started thinking it might be the 35 mb/sec codec struggling too.
Whatever it was, it wasn't very nice - totally unuseable for my needs for sure. But after lots of folks suggesting that there wasn't a problem (along with many others saying there was), I got another EX1 to look at again thinking maybe I was mistaken. All I had to do was a couple of slow pans along my mantlepiece with some birthday cards on it and the effect was the same, a real jerkiness, both in progressive and interlaced. This was on TV screen and on Macbook Pro.
Still can't figure it out, and still can't imagine how anyone else could not see it. Or maybe I'm just mad!
Steve

[Patrick Williams]

I think that a lot of what people are seeing as a jerkiness is playback without the proper 3:2 pulldown. With 60i, that shouldn't be a problem at all, and I have no problem with pans recorded at 60i or 60p. However, 24p recorded in HQ mode is only 24 frames per second(23.98 actually), and the only way I've found to get a smooth playback for it is to burn it to a DVD or HD DVD at 24p and let the DVD player or HD DVD player add the pulldown. I can't seem to get Final Cut to add proper 3:2 on output no matter what settings I use. I get better smoother results recording 24p in SP mode where it's converted to 60i in the camera with the proper pulldown--it still has the 24 look, but since it's actually 60i it can cut into a 60i timeline with no problems. If you try to put 24p HQ into a 60i timeline, good luck on trying to get anything close to the proper cadence. even though you would think Final Cut would automatically do the proper pulldown. For my highest quality results now I am using 24p HQ and burning it to HD DVD as 24p. The playback looks as smooth as any movie I have on HD DVD. I'm hoping for the same results with Blu-ray later.

[Steve Phillipps]

I shot stuff at 50i, 25P and 50P and it all looked crappy. Maybe I had 2 dud cameras!
Steve

[Alister Chapman]

Don't know why this thread keeps going round and round.

Skew will NOT cause judder.

The EX3's imagers are exposed for the same duration as any other progressive or interlace video camera working at the same shutter speed. It has a true progressive imager so it will give the same motion as any other similar progressive camera at the same shutter speed. I have yet to see one single example anywhere of a SIDE BY SIDE test that shows this not to be true. All I have seen is people saying, oh I saw one shot I did one day that looked different to a different shot I did with a different camera on a different day. Of course they will look different.

There are many many other factors that will affect the apparent motion or judder of an image. In particular resolution, depth of field, contrast, focal length, focal plane etc, as well how it is played back, the monitors refresh rate, monitor size and monitor type.

I have been using EX1's since early pre-production units were around over a year ago. I have shot air shows, racing cars, extreme weather, traffic and many other high motion objects and have yet to see anything that suggests there is something wrong with the way the EX camera's capture motion.

Skew caused by the rolling shutter is a separate issue. It does not cause judder, why should it? Very fast pans can cause verticals to lean, but at the kind of speeds where it becomes obvious the object is normally so blurred or moving so fast that it's only when you step through the shot frame by frame that you can really see it. Yes if I wave my camera around like a lunatic I can make the image bend like crazy, but that's not how I and most people shoot so it's not really a problem.

Until someone shows me a side by side shot with an EX and another camera, both at the same frame rate, focal length, pan speed etc that shows different motion handling it is my opinion that the claims the the EX doesn't do motion correctly is nothing but unsubstantiated Hearsay.

[Piotr Wozniacki]

I second Alister. People tend to pass judgements based on the preview they're getting off the EX stuff - sometimes using inadequate equipment (like too slow CPU, poor graphics, etc.) - please remember we're talking full 1920x1080 raster here, and the compression of 35Mbps. Some computers may not be up to this task, while being just enough to smoothly display DV, or even HDV. Image tearing is most often the display equipment fault, not the EX issue.

Once you render your EX properly (e.g. for Blu Ray), and play it back from a right equipment - it can be as smooth as silk... Believe me on that!

[Seun Osewa]

Background judder isnt supposd to matter, but to avoid judder at 60p, use a 360 degree shutter. I.e. 1/60.

[Piotr Wozniacki]

Originally Posted by Seun Osewa

Background judder isnt supposd to matter, but to avoid judder at 60p, use a 360 degree shutter. I.e. 1/60.

Yes, I guess there is something to it... Too many people that are after the "film look" think that this can only be achieved by mimicking the film exposure parameters (like 24 fps with 1/48th shutter speed, or 25 fps with 1/50th; generally, a low fps accompanied by the 180 deg shutter - academically correct). They seem to forget about the deeper DOF, inherent in video; my experience tells me that to achieve the filmic cadence and bokeh, I need to either:

- use naked EX1 with shutter off (360 deg) to blur the background thanks to long exposure, or
- use it with the Letus 35mm adaptor, to blur the background thanks to the shallow DOF.

Sticking to fast shutter speeds while maintaining sharp background will inevitably result in very jerky pans!

[Buck Forester]

When I first got my EX1 I was shooting it straight out of the box in 1080/60i. It looked like every other video camera I shot with in regards to motion (much sharper though!). I had never shot progressive before. When I switched to 1080/24p just fiddling around, I noticed the judder effect and thought something was wrong. Even 1080/30p had a little judder compared to what I thought "video" should look like. Then I learned more about it and that's just the nature of progressive. And now at 1080/30p it doesn't look juddery to me anymore. It still does somewhat at 24p but now I understand it's a certain 'look' and it has to be shot accordingly, such as no quick pans without following a subject. But I'm still not a fan (at least at this point) of 24p, for what I'm shooting... I understand if you're going to film-out it's a better format. I just want good, sharp, smooth high-def video. 30p and/or 60i do it for me. I haven't edited my shoots yet and I'm still learning all this video stuff, so I haven't decided what my final shooting preference will be, 60i or 30p. Once I start editing, one will probably be easier than the other I'm guessing.

[James Carl]

Originally Posted by Patrick Williams

I think that a lot of what people are seeing as a jerkiness is playback without the proper 3:2 pulldown.
... the only way I've found to get a smooth playback for it is to burn it to a DVD or HD DVD at 24p and let the DVD player or HD DVD player add the pulldown. I can't seem to get Final Cut to add proper 3:2 on output no matter what settings I use.

Thanks Patrick. The video I saw was edited in Final Cut Pro so I am wondering if the people who are saying they are getting smooth results were using something else or a different setting?
I do recall that Final Cut lets you pick between a 3:2:2:3 and a 3:2:3:2 pull down. Have you experimented with these settings?
If this isn't the culprit what else could it possibly be? Don't the DVD players simply add the 3:2:3:2 pulldown to a 24P DVD?