AVCHD to BluRay loss of quality

[MattV]

I've got a Panasonic HS700 camera capable of 1920x1080p (50p) recording. I used Corel Pro X3 to edit the clips, absolutely brilliant (though a bit slow on projects >1hr). The problem I have is the export/blu ray authoring. I'd like to be able to write the finished product on a BluRay disk without a massive loss in quality as it completely negates the point of the videcamera.

Whether I write the project into a file or directly export to disk (blu ray) I get a choppy video. So something goes wrong with the rendering. What I tried so far:

File type:
- MPEG2, maxed out quality settings - Choppy quality, but no loss in resolution. Sometimes in dark areas I get large pixels showing up.
- H.264, maxed out quality settings- even worse choppiness, but less space taken by the final product.

Options:
- In both cases I have enabled the 'non square pixel' and 'smart rendering'. I tried rendering with them off and there's no change in "chopiness".
- tried exporting the final movie into "BD 1920X1080" standard setting. Result - choppy (almost like an old B&W 1930s movie)
- tried exporting with custom settings (maxed out all settings, bit rate at 20000kbps) - same result
- tried MPEG2 and H.264 - it actually gets worse in the H264 case.

I know that the 50p format is not used in standard BD disks, but even HA footage (25 frames/sec) suffer the same loss in quality after the 'rendering' from Corel ProX3. So obviously I'm doing something wrong. How do I remedy it?

Do I need a new codec and if yes where can I get it from? Isn't it possible to export it natively (without conversion to MPEG2 format - just drop half of the frames to get to the standard 25fps)? .m2ts format is natively supported by BD.

Problem 2.
After I export the movie as a new file, I open DVD factory 2010 to create the disk. I sort the menus, etc, but when I click "Burn" it starts converting the file AGAIN? Something is wrong here, how do I stop that?


I apologise if these problems have been discussed before, but I haven't found an aswer yet, and I've been trawling the forums and help pages since July when I bought the product from Amazon. I have constanlty updated it, and downloaded all the add-on packs, but nothing's changed.

[Ken Berry]

I know that the 50p format is not used in standard BD disks, but even HA footage (25 frames/sec) suffer the same loss in quality after the 'rendering' from Corel ProX3.

The choppiness almost undoubtedly comes because of the 50p original setting in the camera. In effect, if you are converting from 50 fps progressive to 25 fps interleaved using X3, this is done by simply deleting every second frame, giving the final video the appearance of being jerky.

The basic problem is, of course, that X3 is not designed to work with these new 50/60p camcorders -- it was written before they appeared. When a patch or new version which might handle them comes out is anyone's guess. Only Corel knows that...

I think your only option might be to set the camera itself to film in 25 fps interleaved instead of 50p, or find some other software which might be able to convert it smoothly. Does the software supplied by Panasonic do so?

[MattV]

Yes, I have tried to convert the 50fps into 'normal' AVCHD using Panasonic's own HD Writer AE (2.1) supplied with the camera. Unfortunately made the choppiness worse. Suprisingly, the converted clips look very smooth. The choppiness occurs only after they've been re-rendered by X3.

I've even tried Cyberlink's Power director 9 (I think the main competitor of X3) but I still get choppy results (not as bad as in X3 though).

[pyvo]

Have you checked the field order - on both the project and the export parameters ?
From what I remember, HD is Upper-Field First - unlike PAL DVDs and AVI from miniDV.
The default settings don't always take into account your source nor your target formats.