DV Info Net

DV Info Net (https://www.dvinfo.net/forum/)
-   High Definition Video Editing Solutions (https://www.dvinfo.net/forum/high-definition-video-editing-solutions/)
-   -   PPro Output Quality When Panning Camera (https://www.dvinfo.net/forum/high-definition-video-editing-solutions/249536-ppro-output-quality-when-panning-camera.html)

John Toalson August 7th, 2009 01:49 AM

PPro Output Quality When Panning Camera
 
Hi folks,

I just joined the forum in hopes of getting some assistance. I’m using Premiere Pro CS4 with a Canon HV30. I’ve used Premiere in the past (8-10 years ago) but I’m out of practice and I’m new to HDV. My computer specs are XP Pro, AMD 64 X2 Dual 4800+ @ 2.40GHz, 2 gig ram. I know the PC is behind the curve but it’s stable and speed is not a concern right now.

I just returned from a trip to Tanzania, where I shot over 7 hours of HDV. I intend to edit it down to less than an hour with narration, music, etc. and output to Blu-Ray and DVD (I understand that DVD is not HD).

As I began capturing, I decided to test to be sure I’m not losing quality in the process. I used PPro to capture several minutes of video from the camera via firewire, using the HDV 1080i30(60i) preset (the HV30 was set to HDV, 1080i while shooting). The captured files were recorded as Mpeg. So far so good. Without doing any processing or effects, I exported the timeline back to a blank tape via firewire for comparison. Upon playback of that tape, I was disappointed to see a noticeable decline in quality. It was especially noticeable during pans, and has the appearance of poor re-compression.

Scenes where the camera pans over detailed subjects like building textures and leafy trees show a loss of detail and fine pixilation. Scenes where the subject moves and the camera remains still look fairly good, though not quite the same as the original tape. The original tape looks very pristine, with no hint of these problems.

I captured again using the HDV 1080P30 preset in PPro, exported back to tape, and the results were much better, but still not equal to the original quality of the tape. So that leads me to believe this is a problem with interlacing. I’ve also captured using the trial version of Cineform Neoscene, and while there’s further slight improvement, the same problem still occurs when the camera pans.

As far as I can tell, the captured files on my PC monitor look fine, so I believe the problem occurs when the project is re-compressed when exported.

Years ago I used to capture and edit DV from a Sony TRV900, and I was able to output video that was visually identical to the original tape. So I was expecting the same result with HD. I had hoped to achieve that when outputting to Blu-Ray also. What am I missing? Settings? Or is this an unavoidable by-product of the increased compression of HDV. Anything I can do to eliminate this problem?

I appreciate any help you can offer.

Tripp Woelfel August 7th, 2009 06:55 PM

There are limits to the output quality comparisons you can make between DV & HDV. In spite of the fact that you're dealing with a higher resolution, the interframe compression is the biggest letdown. So pixel for pixel, you're starting with an inferior image quality with HDV. You also have more options for "capturing" your footage with it too. You need to make sure that your settings match what you shot. If you shot 30p and capture 60i, you could have problems. The settings have to match.

It sounds like your field order is messed up. You don't state your output format but if you're staying 1080 interlaced, make sure that it's top field first. Also, if you shot interlaced and capture progressive, the footage still has fields in it but your NLE won't know how to deal with them, so they will be done wrong.

The guideline I use is that I edit in the format I shot in. If I need a different output format, that conversion step comes as close to the end of the workflow as possible.

John Toalson August 8th, 2009 01:26 AM

Thanks Tripp for taking the time to respond. I recorded in 1080i, and used the 1080i30(60i) preset in PPro (upper field first), so editing should match the format of the original tape. When exporting to tape via firewire, there are no options for format, field order or anything else like there are for exporting to media. But that preset gave the worst results. The best result I could achieve was using the 1080p30 preset in PPro, even though that seems contrary to normal practice.

I’m beginning to conclude that there just isn’t anything that can be done; that editing HDV from consumer level cameras always results in quality loss, and your post tends to support that. Though I would think forums would be full of people frustrated just as I am. I’m still hoping I’m missing something.

Just to cover a few of my assumptions – I assume that exporting back to tape will give the best quality, since tape was the original source. Am I wrong?

Or would exporting to Blu-Ray give better quality than exporting to tape? I just purchased a Blu-Ray burner, but haven’t installed it yet. My results with exporting to tape have discouraged me from wasting money experimenting with expensive Blu-Ray disks.

If you or anyone else sees a flaw in my process or logic, please let me know.

Noa Put August 8th, 2009 04:51 PM

Try to export as a mpeg2, 1440x1080 with constant bitrate of 25mbs, interlaced and upper field first.
that resulting file should look visually as good as directly from tape. If it doesn't, try mediainfo: MediaInfo to check the file that came from your camera as that should be interlaced and upper field first and 1440x1080 as well.

John Toalson August 9th, 2009 04:23 AM

Noa,

Thanks for a simple suggestion I hadn’t tried yet. I exported to mpeg2 at the specs you suggested and indeed the video looked fine on my computer monitor. So I installed the new Blu-Ray burner, burned one disk for a 5 minutes scene, and the result was the same or close to the quality of the original tape when played on my LCD TV. Far better quality than before. Success!

So that means there is something about the export to tape process that diminishes the quality of the video in my case. It could be the firewire protocol, or more likely my HV30 camera records via firewire in someway that creates the problem. Since there are no options for export to tape, there’s no way to know what it’s doing to the video. So obviously I won’t be archiving the finished project to tape.

I’m relieved that I’ll be able to maintain my Tanzania trip in HD for others to see.

Big thanks to both Noa and Tripp for your help.

Howard Churgin August 10th, 2009 07:02 AM

Quote:

Originally Posted by John Toalson (Post 1195346)

Just to cover a few of my assumptions – I assume that exporting back to tape will give the best quality, since tape was the original source. Am I wrong?

Or would exporting to Blu-Ray give better quality than exporting to tape? I just purchased a Blu-Ray burner, but haven’t installed it yet. My results with exporting to tape have discouraged me from wasting money experimenting with expensive Blu-Ray disks.

If you or anyone else sees a flaw in my process or logic, please let me know.

Exporting to tape should be the best "uncompressed" quality I belive.

Maybe there is an issue with exporting back to tape right from the timeline. Maybe some computer ram or other issues depending on transitions, effects, color correction etc.

You might want to try to export from PPro a quicktime animation video (lossless) with highest quality settings and keyframes etc. let the pc due all the processing and rendering.

This export will be a huge file in HD 1440x1080. You probably won't be able to play it back on your desktop with QT. I know I cant but I can edit the HD fine.

Then import that to its own sequence in PPro let it render (i know its time consuming) then export to tape and see if there is a difference.


All times are GMT -6. The time now is 10:41 AM.

DV Info Net -- Real Names, Real People, Real Info!
1998-2024 The Digital Video Information Network