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Having problems with AVCHD, DNXHD and overall workflow.
Hi all,
I’ve been using Adobe for many years, but this week got the chance to shoot a movie with my DSLR for my kids school project. I’ve built up a nice DSLR rig, audio recorder, mics, etc. My eventual camera will be the Black Magic Pocket camera, and/or the 4K one.. depends on funds. Anyway, I am using a canon T2i and recording on the SD card. What I want to do is transcode my avchd to dnxhd. I’ve tried several programs, so far the only one that seems to work very well is this one called Pavtube. For 35 bucks, it just works. Or at least I think it does.. converts my avchd files pretty quickly. I’ve yet to verify if they truly are DNXHD or not.. but they do come out as .mov files.. they are only slightly bigger than my avchd files though.. which is puzzling to me. I think I chose DNXHD 36 10-bit 4:4:4.. so figured they’d be much larger.
Anyway, I am able to import/edit the files, but where I get loss is how to “resave” them as DNXHD. I am not sure of the correct sequence of events when it comes to color correcting, grading and editing. I am also trying to learn the best way to sync the separate audio files to the video. Been using the hand clap method, but with about 50 video and audio files, it’s been a nightmare figuring out what audio file goes with what video file, much less syncing it up. How do you guys manage recording multiple takes of video and audio and then know how to match everything up quickly in post?
So the problem seems to be..when I choose Export -> Quicktime, I then select the video tab, use Avid DNXHD and all that. But then when I queue, Media Encoder doesn’t have the ability to export DNXHD. No clue why..but I only have FLV, FLC, AVI, and an H264 option. Done a ton of reading and nothing on the net fixes this situation. So then I tried using the direct export of Premiere.. and that too failed with a “can’t open or find output file”. If I switch to AVI or something, it works. So it seems that the Quicktime (7.7.3 windows version, although in control panel it says 32-bit and I am on win8 64-bit) has a bug in it.
Basically after syncing up the audio to video, and cutting the tracks so I have just the clips I want, I was thinking of exporting them to DNXHD, then importing them to After Effects to apply Bullet Time to get more of a movie look, render those out, then finally assemble the movie in Premiere again where the final output is done.
So.. besides my quicktime/dnxhd issues (any ides on how to fix that?), I’d love to get a basic workflow from some of you experts when using any footage that you then transcode to dnxhd, then how do you edit, color correct, color grade and finally output the final movie?
Thank you.
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6 Replies
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So first off, your DSLR is a Canon. The files aren’t AVCHD, they’re H264.
Second…why don’t you want to simply edit the DSLR files directly?
Third…DNxHD 36 is 8 bit and 4:2:2…36 is the bitrate vs your Canon files which hover around 40 Mbits/s max in most situations…DNxHD 36 is an “offline” or “proxy quality” file…low quality, low bitrate, you’re decreasing the quality of your files, not preserving them.
Fourth…QuickTime on Windows is 32 bit…you can send Apple a thank you card for stranding us Windows users here if you like, but that’s Apple’s gig. Adobe has to actually use a custom frame server app running in the background to make the ancient stuff work at all…
Overall, I’d say you’re adding about 5 extra layers of unnecessary difficulty to this…
Edit the DSLR files natively…in CS5.5 and CS6, Adobe actually bypasses QuickTime for H264 files that are wrapped as “mov” and your performance will be much better.
In CS5.5 and later, dual system sound can be linked…search “merge clips” in help.
Edit the stuff and add your color correction and your filters in Premiere Pro and output the stuff to whatever you want to use for playback…if you must go out to SpeedGrade, then export to SpeedGrade and bring the DPX frame sequence back in to Premiere Pro after rendering to merge with your audio.
TimK,
Director, Consultant
Kolb Productions,Adobe Certified Instructor
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Thanks for the reply Tim. My bad on the avchd.. I confuse the two all the time.
I’ve read that editing h.264 is not ideal and an intermediate format like dnxhd is better to work with. As well, when I get a BMCC, it will use either DNxHD or ProRes.. I’d prefer DNxHD being Windows based. So I wanted to “practice” using that format.. not that it matters once it’s brought in to PP. But I think for this project, I am going to do as you suggest as I am having too many difficulties getting everything to work right. I am curious though.. if I were to use DNxHD as the actual source (from a BMCC for example), is there a way to save the edited DNxHD from PP? The only option I seem to have is the QuickTime wrapper. I know there is an MXF wrapper but I don’t see that option anywhere? The other reason for transcoding or at least I thought was a good reason to do so.. is because I was trying to sync up the audio to each clip I have, then export the audio/video together again, so that I can give those clips synced up to the teacher so she can assemble the clips in her editor as she wants. I thought that if I edit DSLR footage, then render it again, it adds more compression.. then she’ll get it, assemble it and the final media file will be compressed even more.. is that not the case? Is there some way to just save the file as is but have audio added without recompressing the video more?
So basically QuickTime on Windows 64-bit is a problem and shouldn’t be used or relied upon?
As for audio, I had one boom mic plugged in to my camera and two mics + the two on board mics on my DR-40. My hopes was to use the clap method (which I did most of the time) to sync up.. however I later discovered that I had my DSLR mic turned off for 1/2 the video.
What I was more interested in is how, while filming you pros keep track of external audio clips to the video clips? We’re not a pro set so a clapper board would take too much time. In fact with school kids and during school hours we’re kind of rushed to get each scene going so they have some time to learn each day as well. I’d love to have more time to set things up each shot, but the teacher (director) is in a bit of a rush. Sadly my DR-40 headphone socket broke so I can’t monitor audio anymore either. In my rush I stepped on the cord and bent the dang socket a bit.. at least the recorder still works. Anyway, was wondering if writing something down somehow helps? Back in the tape days, I could mark down the offset on the screen, since I’d have to rewind then play it back while I captured. But with media files on both the DSLR and the audio recorder, I am not quite sure how to match everything up. For the most part, I am trying to stop/start both the dslr and the audio at the same time.. but I didn’t do such a good job of that yesterday.
I picked up Magic Bullet Looks and also Magic Bullet Mojo.. I figured if I could clean up the video a little bit first (lighting in classroom is horrible and again..no time for any sort of lighting setup), then apply Mojo and/or Looks, I think that should be good enough for this. Trying to give it a movie-like look.
Thank you again.
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QuickTime works…the reason you thought it was 32 bit was because it is…
DNxHD in an MXF wrapper isn’t available in CS6…it’s on its way…
Converting to any other format does some recompression…even if converting ‘up’…but you can’t use the lowest bitrate DNxHD flavor to preserve quality anyway.
You can sync dual system sound with clip markers in PPro, or you can use TC, or beginning/end of clips…you can use Plural Eyes if both clips have audio…
Editing H264 isn’t really that much of a problem if you have a reasonably capable system. Premiere Pro edits with all video decoded to 32 bit float and 4:4:4 color sampling…so if your system can play back the H264 material, making all your material 4-5x larger may not be necessary.
TimK,
Director, Consultant
Kolb Productions,Adobe Certified Instructor
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To be clear, if I take the original source h.264, sync audio, cut it up a bit to get just the parts I need, there is no way to just save it without re-compressing it again? What if I save the project itself, and don’t export the edited/synced clips? I assume that saves the in/out point refs, but doesn’t do any extra compression at that time? In other words, if there is no way to just save the fixed clips for later assembly (possibly in a different app) without more compression being added, can saving it as the project avoid this until we’re ready for the final output?
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I agree with Tim’s recommendation to edit the source H.264 footage. But if you choose to create intermediate files, apply the Fast Color Corrector effect to the source H.264 footage and change output levels to 16-235 prior to rendering with DNxHD. This will ensure you preserve the full range of luma and chroma data (although some fidelity will be lost in the transcode). Alternatively, use a 422 YUV codec instead. Please refer to this post for additional information.
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The project would preserve the audio links in context, but you would have to export the linked clips (keeping in mind that many file formats only support 2 audio tracks) to something else to use the clips witj the dual system audio actually embedded or attached to the media file.
TimK,
Director, Consultant
Kolb Productions,Adobe Certified Instructor
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