When to de-interlace?

[Eoin Ryan]

I don’t send mine to compressor. The fcpro QuickTime file is dropped directly onto my iDVD menu. PAL professional quality two pass selected.

[Sean Oneil]

[Peter Berthet] ”
Playing de-interlaced footage on a normal CRT monitor will not yield overly positive results.”

That not an accurate way of describing it. It depends on how you deinterlace it. Done properly, it will look exactly the same on a CRT as it will on anything else.

Sean

[Sean Oneil]

[Eoin Ryan] “Also can someone explain why people shoot interlaced anyway?”

Because that’s all there was for 50 years.

[Eoin Ryan] “Should we not all be shooting progressive, including myself, if this is the case?”

Depends on what you want. With 50i/60i, you get a higher frame rate (it deinterlaced to 50p/60p). With 25p/30p, you get double the vertical resolution, but half the frame rate.

Sean

[Sean Oneil]

[Chris Babbitt] “It is my understanding that the DVD spec for SD is interlaced, so, there is no such thing as a progressive Standard Definition DVD”

Rafael is correct. There are progressive-scan DVDs. In fact the vast majority of them nowadays are 24p progressive.

DVDs can be authored at either 60i/50i, 30p/25p, or 24p.

Sean

[Chris Babbitt]

Really!
I wish I could remember who posted that about there being no such thing as an SD Progressive DVD.
I also read here that HDMI will not transmit 24p signals. If that’s true, why would they make 24p DVDs?
So, should I be making all my DVDs progressive, if I’m shooting progressive?

[Andrew Commiskey]

I understand, My curiosity is focused on the effect of the properties window and how compressor reacts to it. Because of the way iDVD works, I could understand how these settings could possibly effect the outcome on MPEG2 compression because it is automatic. In the past I have “assumed” (the start of many mistakes) that compressor would ignore these settings and process raw data. If I was wrong then Compressor could be a much better piece of software than I thought it was.
Anyway, sorry for the confusion, I will run some test next week to see.

Best,
Drew

Chaos is the beginning of everything.

[Rafael Amador]

Hi Chris,
If you make your DVD Progressive, whatever the player used, whatever the screen, Progressive or Interlaced, your picture will always look Progressive.
Rafael

http://www.nagavideo.com

[Rafael Amador]

QT player still being a mystery for the users.
What are call “Visual Setting” they really affect the way that other applications read QT files.
Before wasn’t like that, but now if you change the “Scaled Size” of a video file, when that file is imported to FC will show the file with the changes you made, and Square pixels.
Rafael

http://www.nagavideo.com

[Sean Oneil]

[Chris Babbitt] “I also read here that HDMI will not transmit 24p signals.”

Not sure were you read that. Almost all HDMI source devices can transmit 24p. In fact I think that’s part of the Blu-ray spec. Not all HDMI TVs can accept that format, but most of the newer ones can.

Sean

[Chris Borjis]

[Peter Berthet] “Plasma and LCD panels are not interlaced screens,”

true but oddly enough, Plasma displays are so close to mimicking crt that you WILL
indeed see out of field order jitter if the field order isn’t properly flagged
in the mpeg stream of a dvd.

As for the original question….when to de-interlace??

The answer is NEVER.

When you de-interlace you throw away half of your resolution.

There are methods to combine your fields (re-interleave) but
that’s still not as good as shooting progressive from the get go.

A properly processed interlaced clip will view perfectly and
by viewing that DVD you made you saw just that as unchecking
a box in quicktime does not de-interlace the source.

The real problem is too many people see the interlacing on
their mac display and assume thats going to cause a problem.
oddly enough pc’s don’t have this problem.