Optimal encoding and playback

[Brian Maurer]

I recently purchased a Canon HF100, and love it so far. I’m trying to figure out the best way to encode the files that I create, and unfortunately, don’t have any sort of formal training on codecs and proper ways to most efficiently encode. I recently shot a few clips around campus and checked them out on CS4. I shot at the highest quality setting (17mb/sec) and used the 24p mode. Now I imagine this is wrong, but my first inclination when editing this on my computer was to use the AVCHD 1080 24p setting.

I’ve since talked to a friend, and he let me know that the 24p signal is actually in a 60i stream. He suggested that when I do edit, that I select a 29.97 fps interlaced preset. I’ve not yet had the chance to try this, but I was wondering what the right thing to do is here. He did a reverse telecine on the footage I sent him and was able to pull out the 24p signal, but that’s way over my head.

All I know is that the footage that I have, shot using the preset of 24p (which is not true 24p) looks fuzzy when I use it in a new project with the setting 1080 24p. Is there anything you might suggest I try?

The ultimate goal is of course crisp quality. I’m working on a feature that’ll be delivered on our local television channel, then online, then at an art house theater. Your help is always appreciated.

*EDIT*

It's been suggested that I do a reverse telecine to undo the 3:2 pulldown that the camera does natively, to get a true 24p signal. Can one do that with Adobe Premiere Pro CS4

[Battle Vaughan]

Yes, when you do your initial setup in sequence settings >playback settings select your method under 24p capture method check box.
However, I believe your Canon does the canon 24f dosey-doe which isn't a true 24p, but which CS4 supports natively. I have imported full res 24f files captured from an XHa1 with no problem. Fuzzy look: your preview mode may default to a low-res preview if your computer doesn't support a higher res real time preview, but that doesn't reflect the actual quality of the take...or, if your output is fuzzy, check Encoder for a bug that, no matter what bit rate you set in Premiere, it defaults to 1000 in Encoder and you have to change it in Encoder (probably you need 25000 for hdv). Hope this is some kind of help / Battle Vaughan /miamiherald.com video team

PS I have not done AVCHD in this format so I don't know how that affects the above. The playback 24p options are still available in sequence settings in the avchd 1080p setup, however, if you want to use them. My guess is still that you have a default low-res playback (avchd requires a LOT from your cpu) or the output bug I mentioned. 24f from HDV works nicely, can't see why it would not from your camera as well..../bv

[Brian Maurer]

Well, looks like I have two options:

1) Edit the files as 60i in Premiere without having to any sort of rendering (which I hear is ideal for TV /DVD / Bluray output).

2) Open AE, do a reverse pulldown and get the native 24p file, render via AE into a HUGE AVI file, import into Premiere Pro using project settings 1080 24p (which is ideal for internet / computer playback).

The first is ideal when considering space and time, as I don't have to create huge files, and I don't have to spend the time rendering. I'm doing a test right now to see if there is much quality difference. I'm running a 2.8 quad, 4 gig RAM. I notice huge playback issues, and that's most likely due to my RAM issue.

This is already slated to air on television, then internet, then I'm to take it to our theater here (which I assume they're going to want a DVD; if they have bluray, that would be ideal, I think). Course, if I need to make both an internet version, and a HD DVD / Bluray final product, which project setting do I start with: 1080 60i or 1080 24p?

[Brian Maurer]

Additionally, after I run the files through AE and import them into Premiere Pro, the playback lags bigtime, as the files are fairly large. I started by rendering them as AVI, then quicktime. Went from 2.4 gig down to 1.8 gig for 17 seconds. What am I doing wrong?

[Battle Vaughan]

I'm not clear on what you are working toward, but the rule of thumb is to convert as little as possible...

Suggest you experiment with several approaches, using short clips, and see which mode of capture and edit makes the best quality full-res file. Use whatever Premiere will edit natively (without rendering) as this is the most efficient way to get your basic timeline. Import and work with the files as uncompressed as Premiere will manage.

Use that as your basic product and convert that to the other repurposed outputs --- don't convert and re-import and re-convert the same file, you will lose quality. /B.Vaughan

[Brian Maurer]

It just seems to me that the 30p option on the camera doesn't appear as sharp as it should. Our shoot begins in a week, and I'm trying to decide whether to shoot in 24p or 30p. Premiere Pro can work with the mts files without rendering if they're shot using 30p. If they're shot using 24p, there is a short render time. And they work with no lag in preview when editing.

It's only when I run the 24p files through to TMPEGnc to do the reverse telecine to get the native 24p files do I get either a nasty quality image, or a huge fine (1m37sec turned into a 14 gig AVI file). My computer can't work with files that large without completely lagging out. Maybe I'm just missing something, or maybe my compression software isn't working right. Maybe I'm doing something wrong, or maybe I'm expecting more sharpness from a 30p or 24p files that doesn't really exist with this camera. I'm somewhat new to 24p / 30p and just thought that it was a bit sharper than what I've been able to work with.