Why deinterlace true interlaced source?

[Vejita-sama]

In the past (not using big3) when I wanted to either backup a true interlaced source, or encode a captured home movie I just had CCE encode an interlaced MPEG2 (MPEG2 supports interlaced source).

I notice that the AVS scripts generated by DoItFast4U deinterlace true interlaced sources? I always thought that it was recommend to leave true interlaced sources alone?

What am I missing (btw that's again for this great forum, learning a lot as I slowly read through most of the post from the past 6mo).

[hendrix]

it's personal preference whether or not to deinterlace or not
eyes just provides a script for those who prefer to deinterlace thats all...just go into DIF4U's avs script editor and leave the deinterlaced script blank. you don't have to use the default scripts.

[Vejita-sama]

Hmm, yeah I was planning to edit the scripts for comparison. It's that over a http://www.dvdrhelp.com pretty much everyone says not to deinterlaced a true interlaced source :) So I was curious if there was a reason other than 'personal perference.'

Based on past results I think I'll choose not to deinterlace.

[hendrix]

the only reason i would think why anyone would deinterlace is viewing material on a computer monitor vice a tv...interlaced material has the annoying combing effect that tv doesn't....i personally won't deinterlace

[Vejita-sama]

True, but if you play your DVD with a software DVD player it de-interlaces on the fly for you. And of course if you play it on a TV it's fine. Now that I think about it I'm not sure what happens when you play a true interlaced source on a progressive tv. But it stands to reason that it de-interlaces on the fly (other wise how could you watch broadcast TV).

[Eyes`Only]

Why would you go into the AVS Editor and change the interlaced script? Just deactivate the Autodetect button.

One of the reasons some prefer to deinterlace is that progressive video takes less bitrate for the same amount of quality vs. interlaced video. Since you're using lower bitrates and some people want all the quality they can, they choose to deinterlace and use less bitrate so that they can have more available for the main movie.

But like hendrix said, it's a preference. I know some PAL users that can't stand the way interlaced extras look compared to deinterlaced, then I know some PAL users that are the exact opposite.