EX1 and flying birds
 

Been shooting a few tests with a loaner EX1, on panning shots of flying birds against hills/woodland backdrop the background does seem to show quite a lot of jerkiness, presumably the "skew" from the rolling shutter, does this sound the likely cause? Sorry I can't post clips, not geared up for it here. The bird stays sharp, but background is very distractingly jerky.
Steve

Frame rate.

What frame rate are you shooting?

720 25/60 mostly. But on scenic pans at 1080 30P or 25P it also jerks, but less so as the pan's slower of course. You can see the jerkiness on the LCD as you do the shot.
Steve

Try shooting the pan at 1080i and see if the jerkiness disappears.
To me, it always looks a bit "jerky" when I pan in 24p particularly, and less so @ 30p.

Yes, I would think the framerate is the most important aspect here.

Anything under 60i or 60p would have a tough time keeping up with a flying bird against a non-moving background.

To my understanding, the rolling shutter would show signs of bending of straight lines rather than jutter.

But I don't own the camera, so please correct me if I am wrong.

Think about how sports are typically shot and televised. It's either 1080i60 or 720p60 (NTSC lands).

30p and even more so 24p call for SLOW panning. This is not specific to the EX1. It's the nature of temporal motion. Increase shutter speed and you further exaggerate the effect too due to less motion blur.

Yes, a rule of thumb for panning a static scene at 24 fps 180 deg shutter is 7 seconds for an object to traverse the screen. Faster and it will be jerky. Three seconds for 60 fps. But if you are tracking a moving object, generally the audience isn't conscious of the background because it is blurred. However using a fast shutter that freezes the background will cause problems.

I'm used to seeing blurring on Siny 750 and Varicam types, but not judderring which is what this is, seems like it's having a job keeping up with refreshing the complex image.
As for frame rate, it really shouldn't matter - when you follow a moving bird in flight the bird can be sharp at 25P, it's just that its wings will be whizzing up and down so fast it's horrible to watch, and the background again should be blurred by the motion but steady.
Steve

This depends upon the speed the bird is flying.

Try to shoot the same sort of scene with 60p and report back to the forum.

I would like to hear the results.

What was shutter speed/angle?

I was shooting tennis players running up and down court (hence fast panning to follow the players) and had no judder problem at all. This was at 180°. Go to a faster shutter speed/smaller angle you'd certainly get the "Private Ryan" look but you'd know that.

Would it be helpful to anybody else (including ME!) if some of you folks could post some good examples of "judder"....maybe make it a Stickie so we have it always available. Actually, it would be great to have a permanent collection of ANY of the common image problems associated with the EX1 so we are "on the same page". I remember one posting from a few weeks ago showing some "bad" pans but it would be great to have some really solid examples of these anomalies. If this has been done already, I'll shut up. ;)

I was shooting at 60, with 180 degree shutter as normal. As I said, it's not the bird that's juddery, it's the background, the bird is not changing its position in the frame as I'm keeping it central so it's sharp and stable, but of course the background is whizzing along.
Steve

That's why I made note of my tennis shoot. Same thing. Tracking the player but the background did not judder for me. I did see the rolling shutter skew on the background but no judder at all.

Maybe you can post a hi rez example on Vimeo.

If you saw skew, then I guess that's what I'm seeing too, whatever it is it's not pleasant, makes your eyes go funny after a short time!
Steve

Although the skew is very different than judder. Skew is smooth as silk. Background begins to bend as one starts fast pan and straightens out at end of pan. It's currently the nature of CMOS. Red camera has this too.

Given the shots I see it on I think it adds dynamism. The background bends but the subject is fine. Gives a sense of motion and speed to the shot. If you really find it objectionable than CMOS just isn't a good solution for you. Again none of this looks like what I'd call judder (which to me is uneven or "stepped" motion).

I am starting to think that it might not be for me. I certainly don't think it adds "dynanism", just screws up an otherwise nice shot! When the pan stops everything settles down and looks great again - on a still image the EX1 does make very impressive images I must say. Put Flash XDR on it and it'll be even better I'm sure - just struggling with the movement issue.
Steve

Open door maybe, but Steady Shot: On or Off ?

George/

Steady shot Off George, good thought though.
Steve

Sorry Steve, I misread your initial post. You said 25 & 60p.

I would still like to see examples because this is a make or break issue for this camera.

It is not a still camera, motion is quite important.

I would also like to know if this is from the bitrate or the CMOS chips.

if bitrate, then the aformentioned Flash XDR will take care of any weirdness.

Steve, why not post the clip on Vimeo so we can actually have a look.

CMOS, at its current state of design in video cameras, has things inherent to it. As I mentioned, it's even there in Red and that kit is MUCH MORE expensive than the EX1.

Probably, the reason why a manufacturer chooses CMOS has to do with efficiency vs chip size. In the EX1's case it's the only 1/2" chip in a small camera. With Red it's a big chip relative to the size of the camera too. CMOS does do some nice things with light (it doesn't "band") that CCD doesn't too.

Every camera, every technology has a "characteristics" relative to price point or state of tech advancement.

Quite happy to post a clip, but all I can send is the mp4 clip direct from the SxS card as I don't have any way to transcode it to a QT or whatever. Any one got any thoughts?
Steve

I know it's there with the RED, I think that's the reason why just like the EX1 it's actually ludcirously cheap for its spec (much more so than the EX1 even).
Steve

What are you monitoring with? I find the cameras LCD appears to accentuate any stutter or judder. When I play back on a proper monitor it dosn't looks so bad.

LCD, plus TV screen (SD but should only affect resolution I assume not motion), and Macbook Pro.
Steve

Interlace SD TV screen to monitor progressive motion?
I think you'd be better off with an HDTV (1080p).

If you have QuicktimePro you can compress to H264 and post on Vimeo.
Various NLEs have the ability to compress on export to something high quality.

It's just the same on the LCD though. I tried to open files in Quicktime Pro but it wouldn't let me, any idea why?
Steve

Quicktime won't open the EX MP4. You'd need FCP 6.0.2 or higher for the EX codec and use the free Sony XDCAM Transfer tool to re-wrap as mov.

I don't think any Compression app on the Mac handles EX MP4 source yet.

With FCP 6.0.2 and the XFER tool they'll handle the resultant mov file.

Yeah that's what I thought, and why I didn't think I could post clips. I can view on VCL application and also on the Clip Browser software, but you can't do any transcoding etc.
You'll just have to take my word for it!
Steve

The clip browser will export the clips as XDCAM, which Vegas Pro 8 will turn into anything you like. Have I understood correctly that you don't have an NLE able to process your EX files?

Some time back, because this was raised as a most serious problem, I spent time assessing the appearance of fast tracking pans with the CMOS shutter and could find nothing objectionable (and I'm fussy). Perhaps your bird was small in the frame, so the background overwhelmed the image? I agree with Craig on both the points he made; you'll be familiar with interlace artifacts of showing interlaced material on a progressive monitor, and I would expect (but haven't checked) problems for progressive on interlaced displays.

However your Mac should be showing progressive. Certainly no good keeping a camera that doesn't give the results you want.

I've just put a short on vimeo with several bird shots and some very fast pans.
These were shot at 30p, shutter off. They look as I'd expect them to.
Link: http://www.vimeo.com/1016518/l:transcoded_email

Looks good to me. Pretty place, Seattle.

Thanks Serena, Mark. First thing I notice in your clip Mark is just how bloody sharp this camera is, it really does produce tremendous pictures with amazing clarity and nice colours. But look at the shot of the cormorant for instance and I see the background very juddery and blurred, not nice at all, just what I'm getting on my tests. Serena, to me it shouldn't matter if the bird is small in the frame or not, I'm not after something I can put up with, or that's OK if the subject's big enough in the frame that the background won't be too distracting - either it's working or it's not. The camera's not mine, it's on loan, I just got it to evaluate thinkingabout maybe getting an EX3. I'd mostly use this for personal work, as most of my broadcast work is still with 2/3" cams (notably Varicam and Sony 750, but also some Digibeta still).
Thanks as always for the replies.
Steve

There does seem to be what looks like unsteady panning during the cormorant, but the bird is followed well. Couldn't detect that in any other shot. Interesting.

Yeah that's the thing, the bird is followed OK and stays sharp, it's just the background that's juddery, same as my tests. Very noticeable on a diagonal pan from 1 object to another too.
Just extracted some stills to do a pseudo grade in Photoshop and they come out great, in fact they look pretty much like a reasonble quality DSLR (as you'd probably expect froma CMOS chip I suppose). I shot it flat with Cine gamma, and extended knee etc. so looks washed out in camera just like BBC set-ups for Varicam / 750 etc. then alter levels in PS and it looks great with detail and blacks and whites. Just wish I could get around this movement issue.
Hmmm.
Steve

What am I missing here?
Fast pans = judder on any video camera. As Serena mentioned, this is simple math.
The only solution is to slow your pan down.

The video on Vimeo looks pretty good. I do see jumps. My opinion is that its not the camera.

To judge the motion quality of the camera you need a real video monitor and not rely on a computer monitor.

I have noticed on my computers that the motion of the image looks more harsh than it does once I've set up to preview it on my HDTV.

I've not experienced any jumpiness with the EX1 as described here. I have had some issues with pans on the V1U but only when the codec runs out of bandwidth. You don't get jumps but you do get macroblocking.

I do not see macroblocking on the posted footage from the park. I do not think its an issue with the camera but one in the computer if you are seeing jumpiness. Computers do not match the refresh rate of video and you will have judder any time you have a frame rate mismatch between the source footage and the display.

Chris

It's all about temporal motion. That's why sports is often shot at 720p60 or 1080i60.

The rules of panning have little to do with the camera and everything to do with frame rate (and shutter speed).

With CMOS it's possible to see rolling shutter on fast pans but that has nothing to do with judder.

Thing is I'm used to shooting 720/60P on Varicam & HPX2100 and don't see this sort of effect. Nothing has changed in my working or viewing practice. I'm used to seeing blur on these cams and on Sony 750 at 25P, but it's smooth blur not jumpy. I know viewing footage over the net is prone to slow/interrupted downloading, but I'm seeing the same effect on the LCD and TV screen. I just keep coming back to the thought that I'm looking at the reason why this camera that's specced up better than a Varicam (virtually twice the res) costs a fraction of its price.
Steve

I don't think the cormorant is a shot to use as an example because the pan is too inconsistent. I get behind and then rush to catch up. The oddness in the motion there is due to the shooter (hey, it was cold that day!) and maybe the head on the tripod, not the greatest.

I don't agree Mark, I think you've done an OK job keeping up there! And even if you were trying to catch up it shouldn't be juddery like that, it should still be smooth by blurry.
Struggling to get to the bottom of this, it's not something I've seen before in 15 years as a wildlife cameraman, it just doesn't look smooth to me at all - and yet the camera otherwise is close to stellar (clumsy, fiddly buttons an plasticky feel notwithstanding)!
I've looked through clips of mine that I've shot of similar stuff on Super 16, Digibeta, HDCam, Varicam and even Phantom HD and don't see anything similar.
Again, Hmmm.
If anyone wants me to email them a clip to look at just let me know, just it'll be a big file as there is no way for me to downsize it not having FCP.
Steve