Encoding 4:3 to 16:9 (PAL)

[Chuffy]

Thanks AQUAR,
Believe it or not I AM getting my head round this now and the Resize/Aspect Ratio settings are all making more sense. Bit more reading up to do though.

One thing I have noticed and not sure if it's a bug, is when using Yadif. I had been using 'Bob, T and S check' to deinterlace and have just noticed if I add the filter first, as you should, and then crop and resize, it screws up the aspect ratio giving a totally different ratio when you resize. If I do the cropping and resizing and then add Yadif and bump it up to the top of the list so it is first in the chain, it doesn't affect the AR. The files end up with the correct aspect ratio.
Also, if I use Yadif with default T and S check (not Bob) it doesn't screw with the AR, it's just the Bob setting?

As most, if not all of the films I have been having trouble with needed deinterlacing and I was using Bob, this could be part if not all of the problem I was having. Only just noticed this since I have been paying more attention to AR's.

Anyway that could be a whole new can of worms right there.

Many thanks for all your help.

[AQUAR]

Good for you. 
Eventually it will make more sense to just go manual with swsResize.

Deinterlacing is a whole other topic.

You can crop before deinterlacing, but its very specific so as to preserve the relation between field lines.
It reduces the effort required from the deinterlacer (not really much of an issue for todays fast PC's)
Don't ever resize before deinterlacing as the result will be irreversibly messed up.
(Downloaded movies are sometimes messed up in this way).

Generally its deinterlace first then crop and resize. 

Anyway it was fun to have a bit of a friendly chat about video aspect.