Interlaced Material encoding bad quality

[rhayman]

I captured one of my holiday videos at 720 x 576 and want to encode to DVD. The video was captured using picvideo mjpeg at quality 17.

Anyway there is quite a lot of video to encode and the average bitrate is calculated at 2500.

I am only planning to watch this on tv so i thought it would be best to keep it interlaced to maintain quality.

I first encoded the video in cce i used a 2 pass vbr of 0 (min), 2500(avg), 9800(max).
i used the following avisynth script:
AVISource("G:\holiday1.avi")
ConvertToYUY2

When i encode most material i use these settings and the quality is fine. i dont have a huge tv so i dont have to over the top in bitrate.

The quality was really bad however so i tried encoding again using the same settings and a 5 pass vbr. i changed the script slightly to:
AVISource("G:\holiday1.avi")
ConvertToYUY2(interlaced=true)

The quality was better but not by much. Can anyone help, I figure an easy way round it would be to use a much higher bitrate or to encode half resolution but i thought i would ask to see if there where any other other options as i would prefer to keep it all on one disc.

Screenshots:
http://img.photobucket.com/albums/v154/rhayman/original.jpg
http://img.photobucket.com/albums/v154/rhayman/encoded.jpg

http://img.photobucket.com/albums/v154/rhayman/original2.jpg
http://img.photobucket.com/albums/v154/rhayman/encoded2.jpg

[hendrix]

well 2500kbits is rather low for interlaced - if it were progressive you may get away with it...since progressive compresses better. if putting it onto two DVDs isn't an option then i would encode it at half-d1

[Boulder]

You should do some denoising and deshaking on the source with Avisynth. Search the Avisynth forums, you should be able to find lots of information regarding the matter. The capture guide will also give lots of useful hints.

In the future you should also raise the Q in the MJPEG settings, 17 might not look that good. I'd go for 18 at least, preferably 19.