QUESTION: Are you at all familiar with HandBrake conversion software? I am particularly interested in the difference between "Quality" and "Optimise Video." If I set quality to "0" and therefore get message "RF Warning: RF 0 is lossless" does that mean that the quality is at its maximum and optimise only affects space saving in the file? I want highest quality even if file size doubles that of source. Also don't want to wait more than 4 hours for a completion.
ANSWER: I have used Hand Brake but it's been a long time so I'm not very up-to-date, I'm afraid. I'll do what I can for you, though.
Optimize, I believe, will give you the best quality and playability for your intended use. For instance, if the program thinks (or you tell it) that you're going to be streaming the video through Youtube, it will set the output for the optimal settings and file type for that use. That may mean it sacrifices a little quality for better streaming or maybe some other settings are increased/reduced in trade for something else. See what I mean?
When you choose your own quality setting and you see "lossless", that means you are getting the best you can get and there will be no loss to image quality. This also means a much larger file size, longer render time, etc.
Your render time is going to be controlled by a lot of things (RAM, processor, settings, vieo size), including the length of the video so you're going to have to experiment with a lot of things to stay under 4 hour renders.
I hope this is helpful (and correct). Sorry that I'm not more familiar with that software. It's just not in my toolbox anymore.
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QUESTION: Well I would like to think optimize only has to do with file size and what plays it. Assuming I set quality to lossless and change optimize between fastest and slowest settling I noticed one chapter of a DVD can range between 1gb and 1.6gb, which isn't a huge swing considering the time range is between 15 minutes and maybe 6 hours.
Should I assume no matter the playability and size the optimize range will not affect the visual quality? Just the lossless setting under quality controls that?
In order to control file size, the software likely has a hierarchy of things (codecs, image/audio quality, screen size, etc)it can change to reduce the size. Its choices between these items isn't something I know much about. The best way to find out would be to encode it with multiple settings and do a visual comparison. It would be a huge hassle but you'd get the info you need. I think we've all had to do that before at some point.
I wish I was more helpful. Good luck.