Judder vs. Smear at DVinfo.net

Donnie Wagner · August 10th, 2006, 11:13 AM

interesting article, I though it was relevant that 35mm adapters should help reduce HD judder by making background out of focus.

http://hd24.com/dont_shudder_at_the_judder.htm

Justine Haupt · August 11th, 2006, 09:14 PM

Very interesting article... I wasn't even aware that judder's considered an issue with 24p HD (still in SD land). It's funny that, shooting on video, "judder" used to be the last thing anyone was worried about... indeed, getting video to look more filmic (or less video-ish) seems to have been associated with increasing judder, either by deinterlacing or shooting progressive.

Kind of similar to how people used to want shallow DOF at any cost, and now the utmost attention is paid to lightloss, grain... and BOKEH, which I don't think was seen in this forum once just a year ago, but now it's almost an obsession.

Maybe I'm still stuck in 2005, but I'll continue to shoot faster than 1/48th just because I like the judder... say what you will, but I think it decreases the "reality" of the image and increases it's cinematic appeal (to me, at least).

Marvin Emms · August 12th, 2006, 10:00 AM

Interesting article. It would have been nice if it went a little deeper into the subject.

Of course in older video cameras automatic control of the shutter was how exposure was controlled, so dark scenes would smear and bright scenes would judder.

The most noticable judder on TV though is usually during pan and scans from films. Where DOF and exposure compensated original camera movement suddenly gives way to a video pan over to the other side of the 2.35 film, the result is nasty on the eyes, bordering on painful. Happens a lot with the classic 'argument - seen though the car windscreen' shot when converted to 4:3.

I find Justin's reply also very interesting, as the BBC has recently started broadcasting several hours a day of HDTV footage, for example nature documentaries in full sunlight and the footage judders horribly. Rather than blame the camera, I was suspecting that to 'show off' HDTV, they were deliberatly using very fast shutter speeds to get the pixel sharp, photo like frames that make people go 'wow, look at the detail'. Aside from being headache inducing, this sort of judder breaks the illusion of movement for me, and things start to look more like a slideshow.

This reinforces my perhaps otherwise ill informed opinion that where people from film backgrounds may be liable to err on the side of making the exposure too long, people from video backgrounds are more likley to err on the side of far too short an exposure. Speaking as someone formerly obsessed with the quality of every individual frame I can relate to this, but I nolonger believe in it.

Seun Osewa · February 16th, 2007, 12:26 PM

I'm still confused about whether judder is better than smear, but I guess the safe choice for say creating a progressive VCD avoid any camera motion that would result in judder.

If the camera motion is sufficiently slow not to cause judder with 1/48/60/50 shutter speed, will the same camera motion cause smear with the shutter open?

August 10th, 2006, 11:13 AM	#1
Donnie Wagner Regular Crew Join Date: Dec 2004 Location: Pittsburgh, PA Posts: 135	Judder vs. Smear interesting article, I though it was relevant that 35mm adapters should help reduce HD judder by making background out of focus. http://hd24.com/dont_shudder_at_the_judder.htm

August 11th, 2006, 09:14 PM	#2
Justine Haupt Major Player Join Date: Oct 2005 Location: Long Island, NY Posts: 208	Very interesting article... I wasn't even aware that judder's considered an issue with 24p HD (still in SD land). It's funny that, shooting on video, "judder" used to be the last thing anyone was worried about... indeed, getting video to look more filmic (or less video-ish) seems to have been associated with increasing judder, either by deinterlacing or shooting progressive. Kind of similar to how people used to want shallow DOF at any cost, and now the utmost attention is paid to lightloss, grain... and BOKEH, which I don't think was seen in this forum once just a year ago, but now it's almost an obsession. Maybe I'm still stuck in 2005, but I'll continue to shoot faster than 1/48th just because I like the judder... say what you will, but I think it decreases the "reality" of the image and increases it's cinematic appeal (to me, at least). __________________ ~Justine "We are the music makers, and we are the dreamers of dreams" -Arthur O'Shaunessey (as quoted by Willy Wonka)

August 12th, 2006, 10:00 AM	#3
Marvin Emms Major Player Join Date: Apr 2006 Location: UK Posts: 204	Interesting article. It would have been nice if it went a little deeper into the subject. Of course in older video cameras automatic control of the shutter was how exposure was controlled, so dark scenes would smear and bright scenes would judder. The most noticable judder on TV though is usually during pan and scans from films. Where DOF and exposure compensated original camera movement suddenly gives way to a video pan over to the other side of the 2.35 film, the result is nasty on the eyes, bordering on painful. Happens a lot with the classic 'argument - seen though the car windscreen' shot when converted to 4:3. I find Justin's reply also very interesting, as the BBC has recently started broadcasting several hours a day of HDTV footage, for example nature documentaries in full sunlight and the footage judders horribly. Rather than blame the camera, I was suspecting that to 'show off' HDTV, they were deliberatly using very fast shutter speeds to get the pixel sharp, photo like frames that make people go 'wow, look at the detail'. Aside from being headache inducing, this sort of judder breaks the illusion of movement for me, and things start to look more like a slideshow. This reinforces my perhaps otherwise ill informed opinion that where people from film backgrounds may be liable to err on the side of making the exposure too long, people from video backgrounds are more likley to err on the side of far too short an exposure. Speaking as someone formerly obsessed with the quality of every individual frame I can relate to this, but I nolonger believe in it.

February 16th, 2007, 12:26 PM	#4
Seun Osewa Major Player Join Date: Oct 2006 Location: West Africa Posts: 255	I'm still confused about whether judder is better than smear, but I guess the safe choice for say creating a progressive VCD avoid any camera motion that would result in judder. If the camera motion is sufficiently slow not to cause judder with 1/48/60/50 shutter speed, will the same camera motion cause smear with the shutter open?