Motion Blur on HD100U
 

Hey,

I seem to be getting some motion blur when I pan with the HD100U. I.e. When I pan to an object the picture seems to get motion blury until I stop panning. Anything I can do to keep the image I am panning on crips and clear?

Thanks

Hi Brain
I get the same with the FX1 on some of my underwater clips when Im zoomed in very tight an have the whole picture lit up with my HID lights and move with the object.

I will load up a very good example of motion blur soon. Interesting that you have it on your camera though.

Paul

Opps sorry about that

Brain, mistyped...Brian...

Are you on 1/24th shutter? You should be on 1/48th for normal shooting. 1/100 if you want the "Saving Private Ryan" look.

Are you shooting with the Motion Filter on or off?

That's low temporal rate shooting. You should know better than to pan -- except at exactly the correct speed. :)

With 720p I very much doubt it is MPEG-2 artifacts while with 1080i I very much suspect it is MPEG-2.

I'm finding most video shot 1080i is unwatchable as soon as there is any fast or complex motion. It gets killed in the HDCAM camcorder. It gets killed in broadcast -- especially if your local station is stealing 4Mbps for a second channel. We know PBS does this -- in fact in NYC PBS fits two sub channels and the HD is horrible.

In LV stations are selling their "unused" bits to a over-the-air cable service. With 1080i there are no unused bits!

720p60, however, can exist fine on about 16Mbps so it is acceptable -- but morally wrong -- to use these extra bits. :) Use them all -- I say!

Tim, here in Canada I use 1/30 shutter, because I find it nicer, smoother then 1/60. I'm right, or this is just to me?
Also, the "Saving Private Ryan" look is 1/100 in NTSC land too?

Please let me know
Laszlo

Well, film running at 24fps typically has a normal 180 degree shutter and will expose 1/48th of a second per frame. Variable shutters can be closed down to decrease exposure and motion blur (90degrees in the case of "Saving Private Ryan" = 1/96th second exposure per frame.) The same math applies when you overcrank, so shooting at 48fps, would yield 1/96th of a second exposure per frame.
Normal NTSC interlaced video exposes 1/60th per full frame.
Normal PAL interlaced video exposes 1/50th per full frame.

Anything below 1/48th will give unnaturally long motion blur not possible in the film world. This is a tell-tale sign something was shot on video, even if it is 24P (that's why the taxi scenes in Collateral look so "video-like.") The silly thing is the default shutter speed in DV mode on the HD100 is 1/24th (same on the XL2.) I don't understand that logic.

Anything above 1/60th (film or video) will be in the creative zone. For example, sports are often shot at very high shutter speeds to capture details for slo-mo replay.

I don't know what motion filter is, but I do have the motion smooth turned ON. Hope that isn't the problem, as my understanding all it does it to make smoother transitions from Ext to Int and vice versa.

Turn the motion smooth function off. It's an added "feature" meant to smooth out the judder that you sometimes see when doing pans. Keep your shutter at 1/48/sec. as has been recommended in the other posts and you should be fine. (But keep your pans slow or you'll start seeing the judder.)

When I click status it says Shutter off [1/48]. Is that correct? How do i change it? I tried to go into LCD/VF to change it, but I couldn't find it.

Pardon my ignorance, but I am new =). If the motion function is supposed to smooth out the judder, why would I turn it OFF? Wouldn't it make sense to keep it ON?

Also, can't find where the shutter control is. Thanks

The camera "smooths out" the judder by giving you the blur you noted in your original post.

The judder effect is a result of the lower motion sampling of shooting at 24fps. Motion picture camera operators deal with this problem all the time (mostly by slowing down their camera moves.)

I don't remember how to adjust the shutter (I've only operated it for a day or so.) But I'll bet the default shutter speed at 24P is 1/48. I'm sure your operating manual will tell you how to access the shutter controls.

Just push the shutter button in and then rotate it to adjust. However, normally it should be "off" which defaults to 1/48th.

I have tested motion smoothing and think I know how it works.
When in 24P mode, the CCDs actually sample at 48Hz. Only half of those frame captures are actually written to tape, but with motion smooth on, it appears that each of the 24 frames written to tape has a "mixed" image with the another frame before (or maybe after) it. IMHO, this isn't a feature that has much use for any filmmaker. I'm sure it was intended as a way to simulate the smoothness of "interlaced" video, but it doesn't really work.

Here's my test:
Right-click and download these m2t files to your computer.
Motion smoothing off (9.7Mb):
http://homepage.mac.com/timdashwood/...smooth_off.m2t

Motion smoothing on (11.4Mb):
http://homepage.mac.com/timdashwood/..._smooth_on.m2t


Keep in mind that "judder" as you call it has been around for over 100 years in film and filmmakers have learned how to work within the limits of it. If you have an American Cinematographer's Manual you can look up the chart on recommended pan speeds. For a taste, they recommend that if are going to pan 90 degrees on your widest focal length (the book has 35mm focal lengths) then it should take 9 seconds.

Thanks Tim. When I try to move the shutter the screen simply says Shutter off [1/48] and won't allow me to adjust it. I think you adjust it in your frame settings from reading the manual. Or maybe mine has a defect.

Will check out your tests and do some of my own to see if my judder improves. =)

You push it in first to "Turn on the shutter", and THEN rotate to change the value.

I'm sorry for reply to my own message, but you guys just talk about 24p recording. I don't thing I can use that for wedding (I do 95% weddings) Recording 720p30 is a big jump for me anyway from 60i
I love it and I'm ready to learn much more about 30p. I did a few wedding already and turned out fantastic.
I just need to know for 30p recording the 30 shutter is better than 60, or just I see it that way.

Please let me know

Laszlo

I suppose "better" is a subjective term. You may think it looks better, so therefore for you and your clients it is better. Nate and I would disagree (being the film purists that we are!)

Sorry Tim I meant "smoother"
I and my camera man see the movement is smoother with 30 shutter speed
That what I meant. Anyway, if I want to record smoother moving-paning the 30 shutter is smoother than 60?

Laszlo

I personally think it is better 720p30 at 30 shutter, particularly in a dark scenario. I think it blends the frames better and let's more light at the CCD's. Play around with it and I'll bet you find what your limits are with shutter set to 30.

Undoubtedly.

The proper shutter-speed for 720p30 is 1/60th. You can choose 1/30th to increase motion blur but I think this results in mud. Image resolution drops dramatically so what looks smooth on a small screen may look like s**t on a large screen.

I think you are missing a key point -- if you choose the right pan SPEED you will get a good looking pan.

You should also engage the Motion Filter which smooths things out. Are you using it?

Lastly, a pan without following a moving object is not a wise camera move. It's almost as bad as an zoom. IMHO every shot should be composed and static with action within the frame (remember you are working in widescreen) -- or the camera should be moving. Pans and zooms are for birthday party videos.

Laszlo,

I've never shot a wedding but I'm sure it's exceedingly difficult to frame every shot without some panning motion (particularly in close quarters). Have you tried the smooth motion function?

Thanks for all of you.

Yes, actually I never used the camera without smooth motion yet. When I bought the camera I start shoot with it just like with any other video cameras (60i) and I was scared by the results. (Don't forget I came from 15 years experience of 60i) I almost sent back the camera.
But later I start search on the net, I find you guys, and I learn some shooting technics. Two weeks later I shoot my first wedding, and actually I very enjoyed, and the result was FANTASTIC. But we shot 720/30 with 30 shutter speed. The 60 shutter speed was a little bit (I mean just a little more) jittery. Now I'm ready to learn this fomat of video (or film?)
I showed to my new costumers (brides) the already made wedding and since that, I have six new booking and all of them want 720/30 HD. Nobody even realized any jitters. All of them told me: This is look like a movie.. So different... I love it... The picture have a depth.. Look like 3D... etc.
And yes with wedding I think is absolultely unpossible to just frame a shoot with a little, or nothing paning-zooming. But I try to follow this new rules for this beautyfull camera.
Again, I love it and actually right now I searching for the book: American Cinematographer Manual 9th Edition

Any additional help, shooting technics are more then welcome.

PS: If you guys do not mined download my two two mins. basically edited footage from my first ever 720p/30 wedding is here:

http://www.megaupload.com/?d=7D4VC6EV (church)

http://www.megaupload.com/?d=2F2ZFXKG (reception) Here you an see lot's of panning, I following dancers. Don't forget, this was my first try.

I use some free site to upload my footages, so have some advertise, but otherwise it's OK

Laszlo

What would be the proper shutter for 720p24?

I think Tim Dashwood already gave an answer for this a few thread above:

"Are you on 1/24th shutter? You should be on 1/48th for normal shooting. 1/100 if you want the "Saving Private Ryan" look."

Thanks guys. Just wanted to make sure =)

I downloaded Laszlos wedding footage and everyone is telling me of the horrible low light performence of high definition video but Laszlos video looks just fine to me. Either the reception hall had plenty of light or the low light performence of high definition video is adequate for most weddings. Also I didn't see any split screens. But maybe I am hallucinating because everyone is telling me it is impossible to watch high definition video without a 2000 dollar Blu-Ray DVD player and a 4000 dollar Plasma Television.

I didn't remember you were shooting weddings. You've got a lot more freedom.

But remember:

1) You have a much wider screen so you can move back and frame to capture a wider area.

2) You've got more detail so you can shoot wider. However, once you bring it down to SD you might lose the detail so this might not work for you.

Most folks will NOT see jitter when the Motion Filter is used. But, you are right that panning is the one time when the Motion Filter can be fooled.

Try very slow or very fast pans.