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-   -   The Stutteriness, the motion trail, the ghosting, oh the humanity! (https://www.dvinfo.net/forum/jvc-gy-hd-series-camera-systems/74041-stutteriness-motion-trail-ghosting-oh-humanity.html)

Jaadgy Akanni August 21st, 2006 11:47 PM

The Stutteriness, the motion trail, the ghosting, oh the humanity!
 
My biggest problem with the HD100U(a) has been the exaggerated stutter and motion trail/ghosting that happens in 24p. I've tried what Paolo advised me by turning off the MOtion Smoothing, and lot's of other recipes, but I still get the damned stuttery images. In fact, I get that both at 24p and 30p. I just saw a movie teaser shot with an HD100u and again I saw stutter/motion trailing/ghosting. I swear to god, if I find no solution to this I'm gonna go crazy and throw this thing out the window. Somebody help me please. Thank you.

Brett Sherman August 21st, 2006 11:54 PM

Shooting 24P or 30P is not the same as shooting 60i. You have to adapt your shooting methods. Always follow the action. Pans and zooms have to be either really fast or really slow. That's just the way it is on any camera when shooting 24P or 30P.

Stephan Ahonen August 22nd, 2006 12:00 AM

What shutter speed are you using? 1/48 should pretty much give you the same motion look as film. If you're unhappy with the look of 1/48, I would suggest watching a movie some time and seeing how it compares.

It also depends on where you're watching to footage too... Computers, especially PCs, can sometimes drop frames especially from high bitrate and/or processor intensive material. Such as, say, HD-resolution video at 25 Mbits/sec. That's a whole lotta pixels to draw every 24th of a second.

Like Brett said as well, 24p isn't like regular video. You can get away with motion at 60Hz that will completely fall apart at 24Hz.

Jaadgy Akanni August 22nd, 2006 12:05 AM

Quote:

Originally Posted by Brett Sherman
Shooting 24P or 30P is not the same as shooting 60i. You have to adapt your shooting methods. Always follow the action. Pans and zooms have to be either really fast or really slow. That's just the way it is on any camera when shooting 24P or 30P.

Thank you for your response Brett. Can you please elaborate a little. I mean, I haven't been able to get rid of this problem 'cause even when I'm just shooting in a steady position, with now pannning or any movement of the camera, I still get motion trailing on hand or head movements of the subject...I mean, what gives?

Jaadgy Akanni August 22nd, 2006 12:11 AM

Quote:

Originally Posted by Stephan Ahonen
What shutter speed are you using? 1/48 should pretty much give you the same motion look as film. If you're unhappy with the look of 1/48, I would suggest watching a movie some time and seeing how it compares.

It also depends on where you're watching to footage too... Computers, especially PCs, can sometimes drop frames especially from high bitrate and/or processor intensive material. Such as, say, HD-resolution video at 25 Mbits/sec. That's a whole lotta pixels to draw every 24th of a second.

Like Brett said as well, 24p isn't like regular video. You can get away with motion at 60Hz that will completely fall apart at 24Hz.

Thank you Stephan. Please explain 60HZ-24HZ comment and how do I manage those things? And with respect to 60Hz and 24HZ, What should I take care to avoid or maker sure about?

Barry Green August 22nd, 2006 02:13 AM

Quote:

Originally Posted by Jaadgy Akanni
My biggest problem with the HD100U(a) has been the exaggerated stutter and motion trail/ghosting that happens in 24p.

Does this thread reference the issue you're talking about?
http://www.dvinfo.net/conf/showthread.php?t=68745

Scott Jaco August 22nd, 2006 04:39 AM

Quote:

Originally Posted by Jaadgy Akanni
Thank you Stephan. Please explain 60HZ-24HZ comment and how do I manage those things? And with respect to 60Hz and 24HZ, What should I take care to avoid or maker sure about?

You can change the shooting mode in the menus.

HDV24/30p or DV60i will appear in the top left hand corner on your viewfinder.
Also, the camera has a blue/orange LED on the side of the camera that lets you know if you are shooting HDV or SD.

Blue=HDV
Orange=Standard Def.

Greg Corke August 22nd, 2006 01:51 PM

Not wishing to make excuses for the camera but there is a degree of perception in all of this. You have picked up on something that you are now tuning into everytime you watch footage. However, it would probably be fairly true to say an objective viewer may be far less sensitive to this. I know this does not solve the problem but be sure that your viewer will be far more miffed if your content is duff even if you shoot 35mm. Try and de-tune a bit if you catch my drift.


Regards Greg

Tim Dashwood August 22nd, 2006 03:29 PM

Jaadgy,

I'd like to know what kind of display device you are viewing on. Plasma, LCD or CRT HDTV?

Daniel Patton August 22nd, 2006 03:39 PM

Also, would you consider uploading a short example clip if I set you up with space? It might speed things up a bit with another pair (or twenty) of eyes. ;)

Stephan Ahonen August 22nd, 2006 06:48 PM

Quote:

Originally Posted by Jaadgy Akanni
Thank you Stephan. Please explain 60HZ-24HZ comment and how do I manage those things? And with respect to 60Hz and 24HZ, What should I take care to avoid or maker sure about?

Hz refers to the scanning rate of the video. It's superficially similar to saying frames per second, but can also mean the interlaced fields of standard definition video.

As for what to avoid, just try to avoid a great deal of motion unless you're trying to achieve that look. There are guidelines available for maximum panning speeds and so forth at certain telephoto lengths.

Joel Aaron August 23rd, 2006 01:17 AM

Quote:

Originally Posted by Jaadgy Akanni
I'm just shooting in a steady position, with now pannning or any movement of the camera, I still get motion trailing on hand or head movements of the subject...I mean, what gives?

If you wave your hand in front of a stationary camera at close proximity that's a HUGE amount of movement and will strobe.

Usually a film camera is panning or tilting slowly while tracking an object - like your actor. The background is off in the distance, so it's moving a small amount relatively. The actor isn't actually moving much at all because he's being tracked by the pan or tilt.

The more zoomed in you are the worse the effect will be.

Find a shot from a movie and duplicate it with your camera. You should get similar results. You'll probably notice that panning and tilt speeds are generally pretty slow.

Cole McDonald August 23rd, 2006 07:29 AM

http://www.gecko-cam.com/html/Deutsc...ng-Speed-D.htm

John Vincent August 24th, 2006 11:45 AM

Clearly, the camera produces stobbing in a similar fashion as a film camera. But does the compression of the camera (6 frame GOP) increase this effect, or merely add the potentiality of digital artifacts?

Are they seperate phemnomia, or interelated? From my use, I tend to think they are seperate 'problems' and that the stobbing of the JVC is more or less the same as a film camera...
john
evilgeniusentertainment.com

Joel Aaron August 24th, 2006 01:03 PM

Quote:

Originally Posted by John Vincent
But does the compression of the camera (6 frame GOP) increase this effect, or merely add the potentiality of digital artifacts?

Are they seperate phemnomia, or interelated?

Compression artifacts are different - usually they appear as blockiness in parts of the picture. At 24fps it's pretty tough to see. I think the strobing people are seeing is simply 24fps... but it would be easy to test. Grab an HVX200 and do the same test side by side at the same focal length.


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