I have searched and read many threads on AVCHD workflow in MC5 which is all new to me (coming from tape based standard def and Liquid editing). I am getting close to understanding, but am I right in following (I understand many workflow options exist, but these seem right for me):

1. One workflow is to convert AVCHD to DNxHD125 (for 1080i) using TMPGEnc 4.0 for example and then "fast import" and put on timeline for editing.  This seems easiest unless I am missing steps??

2. Another possible one I have read is use Cineform Neoscene for benefits it offers--transcode AVCHD to Cineform Digital Intermediate AVI or MOV (I am on PC).  At one point I thought I could then put that right on timeline and edit, but now it seems from posts I read that I would then need to quote "link AMA with Cineform files; then "transcode" the cineform files to DnxHD (115 for me); delete the Cineform filesfrom the bin; backup the cineform files on external hard drive."  I am thinking this longer route is to use the high quality transcode offered by Cineform Neoscene??

Thank you for patience and advice,

Before MC5 I looked at Neoscene. I think I had a trial and I found the results to be quite excellent (AVI files, I believe). With MC5, I just imported the AVCHD files straight. I used DNxHD120 - 1080i/50. It takes a while to do but I was only going to do it once. All the AVCHD files I had were 17mbps (about 25GB in all, I believe) and they took around 200GB after the import. Looking back, I thought it might be better to have imported at DNxHD36 and then re-link at full quality when the sequence is finished. Maybe next time!

For starters... the question might actually be.... do you need Cineform Neoscene? 

A few advantages using Neoscene: 

1) Color correction is better with a 4:2:2 color space (speically if you shoot "flat" style video )... Neoscene can convert 420 to 422.

2) Neoscene works better with Adobe... so, if you plan on using After Effects with Avid... this may be a good working codec choice.

3) Neoscene does a very nice job of taking 30i and converting it to 24p.  So, if you think 24fps helps create a movie look... then, neoscene is a good choice to achieve this movie look.

4) AMA linking of Cineform Files is very good and efficient  (...BUT it is AVID's stability of AMA linking that can cause problems)

In terms of computing resources needed to edit and render times.... there is NOT a lot of difference between using DNxHD vs. Cineform.  The key (if no the only noticeable) advanatage to using Cineform is the quality level of the video output.

As for workflow... based on what you posted (and, I read it correctly)... converting using TMPG or Cineform appears to not be much different in the number of steps required to get editing level video.

All that aside... the single biggest element is not so much how much preperation you go through to get an editable format for AVID... but, rather how much rendering time will be required DURING the editing and finalizing process.  IMO, that is where most time is lost.... especially true if you are using HD, compositing and/or lots of FX work.

Here is what I would do if you need high quality editing material for final product (especially suited for color correcting and/or 30i to 24p conversion).  I would not recommend this workflow if you are going to be posting material to the web or converting to standard DVD as your final product.

Step 1 - File Conversion*:

Convert AVCHD original video to Cineform Codec - using AVI codec if you are using Neoscene (set to Hi Quality, Higher Quality or Film 1).  Then, take this Cineform codec and convert to a HI Resolution DNxHD format that is 10 bit (ex. DNxHD 220X).  This is a two step conversion process... AVCHD (8bit) to Cineform (10bit) to DNxHD "X" (10bit).   The only reason you would do this is if you want a high quality 10 bit final video.  You can now delete the Cineform video if you like... but, if you have the disk space... I would hang on to it... just in case.

*As I mentioned earlier, if you do not care to have a high quality 10bit format (or will be posting to the web and/or using SD DVD)... then, skip the converstion of AVCHD to Cineform and use only DNxHD conversions... a simplier and less time consuming conversion.

Step 2 - Working Offline:

Now you want to work "offline" (or sometimes also called proxy editing format).

When finished converting from AVCHD > Cinefrom > DNxHD Hi Quality X (10bit).

Import the Cineform or DNxHD X Hi Quality video as DNxHD at the lowest quality avialable into a 720 or 30i format created sequence.  You will now EDIT in this lowest (ex. DNxHD 45) in the 1080x720 (or 30i) format sequence. 

Duplicate the sequence and move to a new bin.

Decompose the sequence with a format setting of 1920x1080.  Make certain you change the format setting BEFORE you decompose.  You now have a 1080 size sequence.  Finally, batch import using the DNxHD Hi resolution qualilty video created in the first step using AVC> Cineform > DNxHD Hi Quality (ex. DNxHD 220X or 1:1X).

Color correct the video.

Then, render all effects.

Export for final viewing.... You now have a VERY high quality finished video.

A few other issues:

You can use AMA linking of the Cineform codecs... however, I have had some problems that caused more grief that AMA linking was worth.  So... yes... using AMA linking would definately be a better approach to use and would eliminate a lot of steps in the work flow... but, if things go wrong... then, the recourse to recover are much more limited than using DNxHD MXF files as editing material.  Also, if you use Cineforms HD version... you can use either MOV or AVI files for conversion.  This is more convient and works better when using the MOV (not AVI) for both Adobe and AVID editing/compositing applications.

In general, my opinion about AMA linking and Cineform (or any codec for that matter) is that while it is a good workflow and is relatively easy to use... it is a workflow that if things go really wrong then AMA linking becomes a nightmare to try and recover work.  And... to be honest, the times I have use AMA linking it worked fine... but, on one big project... it cratered the project.  From that point on, I decided it was better to be safe than to be sorry and went back to using the DISK hogging workflow of Cineform and DNxHD(offline) combo workflow files.

In short... Cineform is a good codec to use if you want to create VERY high quality final output (...perhaps even overkill?).  But, because of AVID's very complicated/confusing and yet VERY flexible "offline" editing process... it makes the workflow much more involved.  I really wished AVID would take a look at Adobe's proxy workflow method since it is soooooo much more easier to use.

This is just one workflow I use... rest assured... there are other workflows that are simplier (...maybe someone may chime in and indicate a flaw in this workflow).... but, no matter the workflow you choose... there always seems to be a trade off between speed and quality no matter the workflow you develop.  Here is a link to a good (and easier - but potentially problematic?) offline workflow video tutorial you may find interesting.

http://vimeo.com/groups/6159/videos/20557784

FWIW  Joe Moya

Thank you Mohammed and Joe for helping accelerate my learning/using HD and MC5. Lots of new concepts, vocabulary, options and appreciate your time sharing knowledge and experience. Dennis