Line Twitter

Paul Kellett · March 6th, 2008, 02:07 PM

Veags ain't much cop at rendering mpeg-2 tho is it.

Bill Ravens · March 6th, 2008, 02:11 PM

I think part of the problem is that the EX1 is so much sharper than prior cameras. While my HD110 is a huge leap over my old XL2, it doesn't display twitter like the EX1 with DETAIL turned on. I know people like the sharp, native look of the EX1 with DETAIL on, but, if you don't like twitter/flicker, leave the DETAIL off.

Piotr Wozniacki · March 6th, 2008, 03:10 PM

Well... yes and no.

As long as your display is not trying to deinterlace, you will not see line twitter from even the highest sharpness. Other artefacts, like edge over-enhancement or noise, yes - but not the typical line twitter.

On the other hand, when you have a twittering display, it will twitter even with sharpness down (perhaps it'll be less visibile, but still there).

When the problem first surfaced with the V1E, Sony adviced to turn down the sharpness in progressive mode from the default 7 (in 0-15 scale) to 3. This of course produced soft image, while the displays that tried to "deinterlace" it still twittered... Therefore, I was using sharpness setting based purely on aesthetic factors, which I also recommend to the EX1 users (for more film-like picture, turning edge sharpening off may be desirable).

Bill Ravens · March 6th, 2008, 03:24 PM

Disagree, not my experience, Piotr.

Craig Seeman · March 6th, 2008, 03:51 PM

I'm getting the line twitter on both my 13" JVC monitor and my 46" 1080p HDTV. Source is 1080p30 downconverted to SD DVD and played from SD DVD S-Video into JVC and Component into HDTV. I maintained source as progressive when downconverting. The SD DVD feeding the HDTV has a "progressive" switch which did not alleviate the problem.

I'm on a Mac. I tried downconverting in Compressor and Episode and another person I know used Bit Vice with basically the same results.

Piotr Wozniacki · March 6th, 2008, 03:55 PM

Line twitter from downconverting to SD is another matter, and involves handling by NLE.

Craig Seeman · March 6th, 2008, 05:46 PM

NLE isn't necessarily being used at all for downconversion.

That might be best handled by professional software designed to do that. Episode Pro is about $900 for example and deals with broadcast formats such as MPEG2 Transport streams etc.

The NLE, in my case Final Cut Pro, is working in the native codec but simply rewrapped with a MOV wrapper.

I assume the Vegas users are also working in the native codec.

My progressive HD video looks find on my HDTV. The twitter is only evident in the downconversion. This happens even if everything is kept progressive.

On the Mac, people are seeing this whether using Compressor, Episode or BitVice so it's not related to software used.

Somewhere, some program or device has some "intelligent" algorithm to handle this or we would be seeing this on movies we rent or buy.

Quote:

Originally Posted by Piotr Wozniacki

Line twitter from downconverting to SD is another matter, and involves handling by NLE.

Greg Hawkes · March 7th, 2008, 04:12 AM

The best result so far for CRT TV.

702/50P vegas using same profile.

Rendered to Pal Widscreen rendered upper field first.
Audio AC3 from Vegas timeline.

The first clip was the problem. Outside shot of theatre, sunny railings 'twittering'
The above almost cured it.
Still not perfect but OK.

Everything else not a problem including strobe spotlights.

Alex Humphrey · March 17th, 2008, 04:50 PM

Quote:

Originally Posted by Craig Seeman

I'm getting the line twitter on both my 13" JVC monitor and my 46" 1080p HDTV. Source is 1080p30 downconverted to SD DVD and played from SD DVD S-Video into JVC and Component into HDTV. I maintained source as progressive when downconverting. The SD DVD feeding the HDTV has a "progressive" switch which did not alleviate the problem.

I'm on a Mac. I tried downconverting in Compressor and Episode and another person I know used Bit Vice with basically the same results.

I had the same issues. I believe it's because DVD's are really only 60i and recognize 24p cadence only in a 60i format. Not 30p. So I was getting weird jitters etc. I changed to 24p, edit, burn to DVD in 24p mode and results? 99% less artifacts and twitters and weirdness. Running Sony DVD progressive scan out the HDMI to 10 different plasmas and LCD's. Same result. Try the 24p at 1/48th to 1/60th of a second. you might like it a lot more.

Now to figure out what detail I need to get rid of edge enhancements... Off, Min, -8? Have to go out and tape some chain link fences and zoom in and out this week.

March 6th, 2008, 02:07 PM	#16
Paul Kellett Trustee Join Date: Nov 2007 Location: Bristol UK Posts: 1,273	Veags ain't much cop at rendering mpeg-2 tho is it. __________________ Round 2 GH5,FZ2000 Last edited by Paul Kellett; March 6th, 2008 at 02:07 PM. Reason: forgot info

March 6th, 2008, 03:10 PM	#18
Piotr Wozniacki Inner Circle Join Date: Aug 2006 Location: Poland Posts: 4,086	Well... yes and no. As long as your display is not trying to deinterlace, you will not see line twitter from even the highest sharpness. Other artefacts, like edge over-enhancement or noise, yes - but not the typical line twitter. On the other hand, when you have a twittering display, it will twitter even with sharpness down (perhaps it'll be less visibile, but still there). When the problem first surfaced with the V1E, Sony adviced to turn down the sharpness in progressive mode from the default 7 (in 0-15 scale) to 3. This of course produced soft image, while the displays that tried to "deinterlace" it still twittered... Therefore, I was using sharpness setting based purely on aesthetic factors, which I also recommend to the EX1 users (for more film-like picture, turning edge sharpening off may be desirable). __________________ Sony PXW-FS7 \| DaVinci Resolve Studio; Magix Vegas Pro; i7-5960X CPU; 64 GB RAM; 2x GTX 1080 8GB GPU; Decklink 4K Extreme 12G; 4x 3TB WD Black in RAID 0; 1TB M.2 NVMe cache drive

March 6th, 2008, 03:55 PM	#21
Piotr Wozniacki Inner Circle Join Date: Aug 2006 Location: Poland Posts: 4,086	Line twitter from downconverting to SD is another matter, and involves handling by NLE. __________________ Sony PXW-FS7 \| DaVinci Resolve Studio; Magix Vegas Pro; i7-5960X CPU; 64 GB RAM; 2x GTX 1080 8GB GPU; Decklink 4K Extreme 12G; 4x 3TB WD Black in RAID 0; 1TB M.2 NVMe cache drive

March 6th, 2008, 02:11 PM	#17
Bill Ravens Join Date: Nov 2001 Location: santa fe, nm Posts: 3,264 Images: 10	I think part of the problem is that the EX1 is so much sharper than prior cameras. While my HD110 is a huge leap over my old XL2, it doesn't display twitter like the EX1 with DETAIL turned on. I know people like the sharp, native look of the EX1 with DETAIL on, but, if you don't like twitter/flicker, leave the DETAIL off.

March 6th, 2008, 03:24 PM	#19
Bill Ravens Join Date: Nov 2001 Location: santa fe, nm Posts: 3,264 Images: 10	Disagree, not my experience, Piotr.

March 6th, 2008, 03:51 PM	#20
Craig Seeman Inner Circle Join Date: Feb 2004 Location: Brooklyn, NY, USA Posts: 3,841	I'm getting the line twitter on both my 13" JVC monitor and my 46" 1080p HDTV. Source is 1080p30 downconverted to SD DVD and played from SD DVD S-Video into JVC and Component into HDTV. I maintained source as progressive when downconverting. The SD DVD feeding the HDTV has a "progressive" switch which did not alleviate the problem. I'm on a Mac. I tried downconverting in Compressor and Episode and another person I know used Bit Vice with basically the same results.

March 7th, 2008, 04:12 AM	#23
Greg Hawkes Regular Crew Join Date: Oct 2007 Location: Basingstoke Posts: 83	The best result so far for CRT TV. 702/50P vegas using same profile. Rendered to Pal Widscreen rendered upper field first. Audio AC3 from Vegas timeline. The first clip was the problem. Outside shot of theatre, sunny railings 'twittering' The above almost cured it. Still not perfect but OK. Everything else not a problem including strobe spotlights.