Bill Lee
Forum Replies Created
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> There are so many disagreements on whether to export to a reference file, export with conversion, or Compressor.
I think that is because the ‘Right Answer” depends on what you want to do, your experience and what your workflow is, all of which can change the answer as to which one is right for use right now. In most cases Export>Using QuickTime Conversion is not the right choice if we are going to later need another transcoding of your video, thus we can eliminate this (exporting from FCP directly to MPEG-2 doesn’t give you the range of encoding options that the other two methods have). Thus we are left with File>Export>QuickTime Movie
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Select the sequence then select the Sequence>Settings
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I’ll agree with Walter on the recommendation to stay in DV, but I’ll have to disagree with Walter on the main reason why (this is possibly a very bad move and may show the world the extent of my ignorance, but I’ll just grit my teeth and continue). I still could be wrong and Walter’s explanation might be the dominant effect on the quality of the final video.
I believe that the two biggest reasons not to change the video from DV to Uncompressed are: a) the difference in field dominance between the two DV and Uncompressed Presets for PAL and b) the different frame sizes for the NTSC DV and Uncompressed Presets.
Video compressed with an uncompressed codec is… well, uncompressed. It has no inherent problems in codec compression artifacts since it doesn’t compress the video. It will however retain the artifacts of its source material or applied filters and processing. I’ll be analyzing the four specific types of uncompressed Preset supplied by Apple: 8-bit Uncompressed NTSC 48kHz, 8-bit Uncompressed PAL 48kHz, 10-bit Uncompressed NTSC 48kHz, and the 10-bit Uncompressed PAL 48kHz. There are other types of uncompressed video possible, but the supplied Presets have particular characteristics that need to be examined.
DV on the other hand has a 5:1 compression of the video – every time you have to recompress it, it will add additional artifacts into the image. The DV decompression is another possible source of artifacts, but you can’t escape doing this at least once (since you have to extract the data), and after that you can lump the compression artifacts and the decompression artifacts into one pile if you are going to do a couple of rounds of compression/decompression cycles. On the other hand, multiple DV compression is not that bad, and certainly not as bad as n-generation analogue tape copies. If you have DV already, you have already taken the major hit on quality – it doesn’t get too much worse than that for one or two re-encodes. I’m assuming that you’re using a reasonably good DV decoder/endcoder here.
So, to get the best possible image, you start off with DV, you have it decompressed, you do things with this video and avoiding compressing it back into DV right up until you have to put it back out to DV tape. It would seem that on the face of it, an 10-bit Uncompressed video format would make a marvellous intermediate format to maintain the quality while you put the video through various processes. Unfortunately it is not, for reasons of Field Dominance in PAL, and Frame sizes in NTSC due to the particular natures of the Uncompressed Presets supplied with FCP.
Field Dominance
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Your DV video is 59.97 (50 in PAL) fields per second, with half of the image captured and shown in every field. Both DV PAL and DV NTSC have lower field dominance, which means that the 1st field is shown first and the 2nd field is then shown (the 1st and 2nd are not refering to when they were captured, but how they are written to the media). If they are shown in the wrong order your picture will look poorest in the areas of motion inside the frame. Apple has an article on this at (docs.info.apple.com/article.html?artnum=58634). The supplied Uncompressed PAL Presets are upper field dominant, so if you bring your DV PAL video into an Preset uncompressed PAL sequence, the size of the frames are the same – 720 x 576, but the fields will be played back in the wrong order and so it will appear to have gross artifacts. Filters that use the temporal difference of 1/50 second between alternate scan lines to generate their results will be incorrect. You could shift the frame down one pixel to fix the field dominance, but then you have just destroyed a scan line at the bottom, and now you have an extra one at the top that needs to be cropped or synthesised, or plain ignored.NTSC Frame sizes
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Since both Uncompressed NTSC Presets have a Lower Field dominance, and DV NTSC also has a Lower Field dominance, then we would expect that we wouldn’t have the same field dominance problems as you would with PAL. There is a problem with the frame sizes though, and the field-based nature of video does cause problems in more subtle ways. DV NTSC has a frame size of 720 x 480. Uncompressed NTSC has a frame size of 720 x 486. When you place the DV NTSC clip into an Uncompressed NTSC timeline, you don’t get it scaled, since the inserted clip is smaller than the timeline frame size, but it is inset into the frame at its natural size and shifted down three pixels (scanlines) to center it in the frame. This has the effect of changing the field dominance, and so the NTSC video acquires the same field order problems as PAL has above. In addition, when the uncompressed sequence is converted back to NTSC DV, the 486 scan lines are compressed back to 480 scan lines, leading to a mixing of the scanlines during the interpolation and thus the destruction of the separate temporal nature of the fields in the frame, further damaging the quality of the video.Testing: I created an DV NTSC video clip with frames consisting of two fields one of black scan lines and the other of white. This is the worst case scenario, and thus should demonstrate it quite nicely. I imported this into an 8-bit Uncompressed D1 sequence, and it centered the video, down three scan lines from the top. I then exported this video back out as a DV NTSC video clip, and viewed it in the QuickTime Player, ensuring that the High Quality option for video was turned on. There you can see of the deleterious effects of the scaling, especially when compared to the original DV. Secondly I created an animation in Motion, consisting of a white ball about 10% of the height of the frame on an NTSC DV timeline with a black background. I animated this diagonally left to right, and exported this out with field rendering turned on, but motion blur turned off. This rendered clip was imported into the same Uncompressed DV used above and played back at 100% in the canvas. Each field was clear and sharp, demonstrating the comb effect of interlaced video on the left and right edges of the white circle. I then exported this Uncompressed NTSC sequence as a DV NTSC movie, opened it in QuickTime Player, turned on High Quality and looked at the video. There were obvious scaling issues.
I also tested a similar animation in PAL DV inside a PAL Uncompressed sequence, and it took a while to turn off all the settings designed to save our eyes from flicker on my external Digital Desktop preview. I tried to see if my PAL monitor would show the difference between imported PAL DV and imported PAL DV shifted down one pixel, but couldn’t see a difference in the two clips. This test therefore remains inconclusive, and if somone with a better setup and broadcast monitor could make this test and report back as to whether there is an actual difference in motion artifacts due to field order display.
Notes about the uncompressed and the DV codecs:
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The default Uncompressed PAL and Uncompressed NTSC formats offered by FCP have certain characteristics that make them unsuitable for direct use with DV clips. You can make your own Uncompressed format that would be kinder to your DV, matching the frame size as well as the field dominance to avoid the problems I’ve discussed above. The question is: Is it worth it? Let’s first have a look at the issue of loss of quality from encoding/decoding losses.When you place a DV-codec clip in an 8-bit Uncompressed sequence, the video will require decompression before being played back and it may require rendering to play it back in real time. The render file will be uncompressed video, and should only suffer from round off error in being decompressed. If your uncompressed sequence is 10 bit, then your round-off error is a 1/4 that of the 8-bit error, bearing in mind that your source DV video will only give you 8-bits of information and you can’t retrieve quality already lost: you can only try to maintain what you have left. If you apply a transition, filter, or colour correction to that clip, the source DV is decoded again, the calculations made, and the render file generated anew. If you have nested sequences inside that sequence, any render files from the nested sequence timeline will be used instead of the original files. Too deeply nested and rendered sequences can be a source of accumulated round-off error but won’t suffer from lossy compression accumulation. You can force the original source files to be used instead of the render files by using the Render Manager to delete the intermediate render files of the nested sequences, and then further decrease the error in calculations by turning on the High Precision YUV in the Video Processing Sequence Settings. The number of DV re-encodes can still be just the same as in a completely DV-based sequences, and the intermediate uncompressed codec is not nearly as subject to quality drift if you are using intermediate render files from nested sequences. As Walter pointed out, viewing your uncompressed video on an external monitor is not going to allow you to make accurate decision on how the final product will look, as it will need to go through another DV encoding before it is ready.
When you place a DV-codec clip into a DV sequence you should want to end up with a DV-codec encoded output, otherwise you may be doing an unnecessary DV encoding. The DV still has to be decoded to an uncompressed format, it just happens ‘underneath the hood’ where you can’t see it. If you have turned on High Precision YUV in the Video Processing Sequence Settings, then all the filters, transitions and adjustments are done in high precision calculations. The use of nested render files will cause generational quality loss, so you might want to remove these intermediate render files before a final render, so that the DV-encoded video is decoded once only from the original DV encoded media. Then the video is encoded back as DV, maybe as the final version to go back to tape or may be re-encoded in another format. If you have to work on the video in other applications, then the need to export as DV and later reimport as DV might be a reason to use an intermediate lossless compression codec such as PNG: see(lists.apple.com/archives/quicktime-users/2005/Jul/msg00200.html) for its advantages over the Animation codec. You gain the biggest time and quality advantage if your video requires no processing at all, in which case the output video data is exactly the same as the input video data. If you have nested DV sequences, just before you are finished with the project, delete the intermediate render files and just generating render files for the outermost sequence will maintain the highest quality video.
The other question is: Can my playback system handle my custom DV-compatible uncompressed video, because if it can’t then you’ve created a workflow that is far less efficient than a DV-only workflow. Even then, the non-standard nature and tweaking required to make the DV-uncompressed workflow successful make it less attractive.
With care, the DV-only workflow can be just as accurate as an DV-Uncompressed workflow, if you are not round-tripping the video with another application, and remains a simple and well tried workflow with predictable results.
Bill Lee
“Darn, that took a long time to test and write up” -
Your timeline (sequence) audio setting don’t match your imported audio settings, so when it attempts to play back your audio in the timeline format, it is not keeping up.
It’s a classic problem in FCP, especially with mp3s and Audio CD-sourced files.
I presume this wedding video is going to end on DVD-Video (PAL). If so, go to Final Cut Pro>Easy Settup
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I don’t know for sure, since I bought FCP 5.0 and then bought the 5.1 upgrade.
But, knowing the cost of re-editing the manuals and reprinting every time an upgrade is released is prohibitive, then I believe that you will get the set of 5.0 manuals and a drop-in upgrade package of disks and possibly even a thin booklet of update notes.
This is not really going to matter, since you say you are just starting, and many of the notes tell of how something that was supposed to have worked, now indeed work correctly. Here is a link to the changes made since 5.0: manuals.info.apple.com/en/Final_Cut_Pro_5.0_lbn_z.pdf. Browse it once, and it it makes no sense to you yet then that is good. If you need anything in the updates for your particular setup or workflow, then read that bit more carefully. Once you install FCP 5.1.2, you have at your fingertips the entire manual, as a searchable pdf (but apparently not the 5.1+ updates). My manuals are still in their box, since it is usually faster to search in the pdf file available through the FCP Help menu. Buy the FCP 5 Peachpit Apple Pro Training series book and do all of the tutorials, since it is the training material used in the instructor-led Apple approved training. The supplied manuals are reference/background materials, and for most people are a hard slog.
Bottom line, save your money. Get the cheaper package for less, then do the cross-grade for US$99 (before Dec 20).
Bill Lee
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At the moment, I’m using a PowerBook to edit, and so it has to be an external drive. I carry around bunch of 2.5″ FireWire drives that I use as storage, as well as having larger 3.5″ FireWire drives while working in one place. I’m currently working only with DV, but have used other formats in the past on desktop Macs.
I usually duplicate bootable drives using the Restore function of Disk Utility, but also use the command line utility ASR as well as CCC. What’s most frustrating with all of these programs is the occasional failure to copy, which repeated attempts to copy won’t fix. Sometimes these can be resolved by repairing the disk that is refusing to copy, at other times it won’t. I discovered that disk corruption of some files may be causing a copy attempt to fail – and found that if you do a drag copy of the disk in question, you should discover which files are preventing the copy from proceeding. Trash those particular files – they are already corrupted anyway and can’t be fixed – and redo a Restore in Disk Utility. A drag-copied version of a boot disk is not usable as a boot drive, but it can be used to work out which files are creating problems with that copy.
docs.info.apple.com/article.html?artnum=303124 is a list of the start-up keys for Intel-Macs, and you can see that the Option key held down will still allow you to temporarily boot from an alternate boot disk, same as the PowerPC-based Macs.
I don’t know about SuperDuper, but the developer of CCC says that it will work under Rosetta emulation.
If I had some disks mounted internally, I would either set up a disk as an alternate boot disk, or partition one of those disks as a bootable volume. Since it is there mainly for emergencies and testing, it doesn’t have to be as fast as the regular boot disk (but it would be better if it is). It will depend on the media you are regularly using as to what is adequate as an alternate boot drive for longer periods. Since software problems are more likely to cause system failures (as long as you replace your drives every few years), a drive partitioned into two should be able to have two bootable volumes on the one disk, but with the risk that a hardware drive failure can make both of them useless.
Bill Lee
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If I understand it correctly, Page IV-100 and IV-101 of the FCP 5 manual should have the settings you need to do what you need to do.
You must understand the Offline/Online Editing Workflows on Page IV-54 as well.The reasons are bound up in the concept of what a Master Clip, affiliate and independent clips are, and how they relate to each other. Understanding Page IV-41 onwards: “Working with Master and Affiliate Clips” helps to build sequences that can be onlined and offlined easily and don’t have lots of duplication in the captured media.
Essentially, master clips (denoted by the check mark in the Browser, or under the Logging tab in Item Properties) contain references to the media files stored somewhere accessible by your computer. Clips dragged into the timeline from these master clips are affiliate clips that are related to these master clips, although these affiliate clips can have certain different characteristics such as In/Out points. When you change the name of an affiliate clip, the master clip changes its name to this, and so do all the other affiliate clips change their names to this new name. If a clip in a sequence doesn’t have a master clip in the Browser, it is called an independent clip, and can be converted from an affiliate clip to this independent status. Since this independent clip has no master clip, any media file refered to by it is considered not-the-same as a media file used by master clips, even if it is the same actual file. You can create master clips for independent clips using the Tools>Create Master Clips, or bring an independent clip back into the fold of affiliate clips linked to a master clip.
To avoid multiple captures of your TVCs, you need to ensure that you have Master clips for all the clips in use in your sequences, and then capture these master clips. Once you have captured these Master Clips, then all of the affiliate clips which rely on these will show they are Online and ready (only independent clips left in the sequences will remain Offline, since they have no way of knowing they should be using the source Media).
Bill Lee
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[Dan Powers] “We currently have two 24″ Dell displays and when you set the Apple to display at the native resolution, the dell monitor says it cant do it. So we are running in non native display and viewing the images stretched! That sucks.
We cant find the problem with the display resoltion cause Dell says it is an apple problem. Apple says it is a Dell problem.”Dan have you tried out the DisplayConfigX utility (www.3dexpress.de)? My copy cost me all of US$12 a couple of years ago (maybe it’s gone up). Unregistered version don’t have all the configuration capabilities that the registered version does.
This cute little utility will allow you set all sorts of timing and rates for your (computer monitor) output video, so that you might be able to placate your Dell’s by outputting a non-Apple approved output signal.
Cheers,
Bill Lee -
NTSC DVDs are likely to be OK in Australia, where I am.
Most DVD players should play NTSC, in a conversion mode where it plays back (720×576) PAL at 60 fields a second so that it can be played back on most recent Television sets/monitors. Some don’t have that conversion mode and instead produce true (720 x 480) NTSC at 60 fields per second, necessitating the use of a monitor or TV that will play back NTSC, as many will do. Most modern TV/Monitors will auto-sync to 50 or 60 Hz field rates, some will also do the direct NTSC playback thing. If he needs to project, then most projectors should be OK with PAL at NTSC rates, if not NTSC playback directly.
shopping.yahoo.com.au/b/a/cp_127701_filter_player_type_dvd_player.html will show you that many of the DVD players now on sale in Australia are PAL/NTSC. Of course the player where the DVD needs to be played might not be new.
The other thing to keep in mind is that not all players will play burnt DVD-R disks, so think of a backup scheme that your exec can use if he turns up and can’t play his disk. NTSC/PAL VHS tape players are even less likely to be available, so that is not likely to be a reasonable back-up plan. Two disks are better than one, especially if he is doing a number of talks – leaving the disk in the player at the last location should not be a catastrophe.
Personally I would send him with three disks, two PAL and one NTSC, and the video file on his notebook to be sure, especially if he is doing a lot of shows on the road.
Bill Lee
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“Apple Pro Training Series: Optimizing Your Final Cut Pro System”
http://www.peachpit.com/title/0321268717Contains a lot of the stuff that you need to know about setting up, maintaining, and recovering after problems with Final Cut Pro.
As a general rule, I try to run standard as much as possible, since unless you write down every tweak that you do, you’ll never remember it months or years later.
If you have the original disk, using Migration Assistant can make most of your applications and tweaks return. You can run it at any time and create a ‘new’ user login that has a lot of the stuff from the old as well move many of the applications to your ‘new’ computer.
I’d agree with many of the posters: an alternate boot drive configured and ready to go makes disaster recovery much easier, as well as being useful for troubleshooting problems with your existing system.
Bill Lee