I'm starting a movie that was shot with SONY XDCAM EX, 1920 X 1080, 25p

Does it make sense to import the footage in DNxHD 185 X or will I have the same quality with DNxHD 36?

I'm running MC 3.1.3 (Mojo SDI)

DNx 36 and 185X are not the same, so you would not have the same quality.  

But, depending on how you're importing the EX material, the resolution is most likely already set by the camera upon recording it.  Most likely something in the 17Mbit or 35Mbit variety

The plan is to export from Sonys clip browser to MXF for NLEs (don't want to use Avid AAF, because of the relink trouble)

From there importing the MXF files to a Avid Bin.

What resolution should I use for best results.

I imported one test clip with DNxHD 185X and DNxHD36. I can not see any difference so I'm a little confused what resolution to choose.

DNxHD 36 is an offline resolution. It is however very good, but I would not use it unless you are planning to go through an online process later to reconform your edit to a higher resolution.

While you may not see much difference in the shot you've tested, there are definitely cases where you will see the difference, and DNxHD 36 will not survive effects and later recompression as well as a higher bitrate (120 or 185)

I have been following this thread because we hope to be shooting with the Sony XDCAM EX 3 sometime soon. If the camara HQ is 35mb per second, what would be the advantage of transcoding to higher than DNxHD 36? I have always figured you can't add information.

Thanks as always and I hope my question helps the original poster.

John

I found out it doesn't make any difference what resolution I choose at the Import Dialog.

The clip will be imported in XDCAM EX 35Mbit resolution. So I'm working natively. This should be fine.

Is there a way to import XDCAM EX with a DNxHD Codec?

relaht:

I found out it doesn't make any difference what resolution I choose at the Import Dialog.

The clip will be imported in XDCAM EX 35Mbit resolution. So I'm working natively. This should be fine.

 

Is there a way to import XDCAM EX with a DNxHD Codec?

If you do not have a Nitris DX system then you will have to transcode the material to DNXHD after import. I find that doing a rough cut in Native XDCAM will reduce the amount of material (and therefore time) that I have to transcode for final effects and finishing.

I would just keep it at the native resolution of 35mbs EX.  You don't take that much of a hit when rendering or doing effects.  One of our shows was 27 minutes long with color correction on every clip and it only took about 25 minutes tops to render that out.  If we put a color safe on top of that, it only took another 25 minutes.  That's really not that bad considering the amount of time it would take to transcode your hours of uncut footage before the edit.

The way XDCAM EX gets the data into 35Mbit/s is very different to how DNxHD gets the data into 36Mbit/s. So while the numbers are nearly the same, the method employed is very different.

Basically XDCAM EX is a Long-GOP compression format, it discards information from many frames and only records data about things that change between frames. This is a very good way to get images into low data rates (it's what DVD does) but can have problems in shots that contain a lot of movement and fine detail (a swift pan past many leafy trees will really push XDCAM EX at 35Mb/s). While it's visually very good, EX does introduce visual and compression artifacts.

DNxHD is different using intra-frame compression - each frame is compressed by itself without regard to it's neighbors. It needs a lot more data to achieve the same results, but doesn't suffer from the motion artifacts that temporal or Long-GOP compression does.

If you convert a format that's already suffered some loss in a Long-GOP compression into an intra-frame compression at low bitrates then the artifacts and problems seen in the original Long-GOP footage will be exaggerated.

To retain all the quality and detail present in the original XDCAM EX footage, you would need to use a DNxHD resolution at a significantly higher bitrate, or else you risk amplifying existing imperfections in the footage.

However, Avid supports XDCAM EX natively in one of two ways - direct import of MXF media created with the Sony Clip Browser (still native XDCAM EX video, just wrapped in an MXF file wrapper) or with AMA access, by directly reading media from an SxS card, or from a folder on a hard drive.

But, being a long-GOP codec Avid doesn't create new XDCAM EX media, meaning any effects or transitions that need to be rendered will be created with a native Avid resolution (such as DNxHD). You can edit entirely with native media only rendering where necessary, or edit and then consolidate to a mastering format for finishing.

Thank you everybody helping me on this topic.

Finally I understand the whole process. Thanks again.

"Avid supports XDCAM EX natively in one of two ways - direct import of MXF media created with the Sony Clip Browser (still native XDCAM EX video, just wrapped in an MXF file wrapper) or with AMA access, by directly reading media from an SxS card, or from a folder on a hard drive."

I'm doing something wrong using the Clip Browser because the XDCAM EX clip and Sequence with the clip remain OFFLINE. Here's how I think the import should be done reading Avid's pre-AMA documentation.

Open the Sony Clip Browser. Use Preferences to define an “OPAtom” folder. (I put it at root.)

After selecting the files you want to import, export them to the Avid MediaFiles/MXF/1 folder which I have in root. Sony’s Clip Browser rewraps these .mp4 files as .mxf files and places them into the OPAtom folder.

During the rewrap, the Sony Clip Browser exports an AFF file to the Avid MediaFiles/MXF/1 folder. This does occur and MXF files get put in the OPAtom folder. So far, so good.

When MC starts, it warns the AAF file is not an MXF file -- which is true. So I drag it to root and restart MC. Now no warning -- good.

To import the .mxf clips, I import the AAFf file into a Bin. The Bin SHOULD now be filled with the XDCAM EX clips plus a Sequence with these clips. Both items appear, but OFFLINE! However, the CoreMIDI.framework starts bouncing! Something is being done -- I think.

And, I have no idea why Avid MediaFiles/MXF/1 folder has a "Creating" folder with a "msmFMID.prm file that has a time equal to the import.

What am I doing wrong?

PS: Is an AFF file supposed to be written per clip -- or only one file for all the clips re-wrapped at anyone time?

Close but not quite - Using the Avid AAF method from ClipBrowser you get two specific output for each clip - the first is a set of OP Atom MXF files that Avid can read natively, the second in an AAF file that contains no essence, only the metadata.

You need to set the OPAtom folder to be one of Avid's MediaFiles directories (eg. Avid MediaFiles/MXF/1) because that is where ClipBrowser will put the MXF media files, and Avid will scan and index them in that directory.

Then you need to save the AAF files somewhere, but not in that MXF directory - I'd choose to put them in a folder in the Documents directory, or on the Desktop, or something like that.

Once you import the AAF files, assuming the MXF files have been put in the right place and indexed, then they will link to that media. You will have a sequence and a clip for each EX clip, you can delete the sequences, they simply act as a holder for the clips.

However, it's very important to note that if you lose the media you have created (ie. the Avid Media is deleted) you cannot relink, even if you follow exactly the same procedure to convert the clips again.

I wrote a more detailed article about this on my website: XDCAM EX Workflow in Avid

"You need to set the OPAtom folder to be one of Avid's MediaFiles directories (eg. Avid MediaFiles/MXF/1)"

Thank you.

It sounds like you are saying create a folder called "OPAtom" within "Avid MediaFiles/MXF/1" folder, but I think that's not true. I think you mean use Preferences to point the Browser to "Avid MediaFiles/MXF/1".

If I'm correct, what's odd is that Sony Browser Preferences will not accept "Avid MediaFiles/MXF/1". After clicking OPEN on the "1" -- Preferences always returns only "/". "Avid MediaFiles/MXF/1" is lost. So, I left it at the default "Avid MediaFiles".

The second odd thing is that during export when you browse to, for example, "Movies/AFF" you cannot set "Movies/AFF" -- you only can specify "Movies" So, .the .aff file ends up in "Movies" -- not "Movies/AFF".

Something seems very wrong with version 2.5 browsing.

OK -- so now I manually drag the .mxf files from "Avid MediaFiles" to "Avid MediaFiles/MXF/1" and the .aff file from "Movies" to "Movies/AFF". As I understand it, files are now where they ought to be.

Starting MC does a scan and two files are created.

Importing the .aff brings in the clip and a Sequence. Success at last!

So Avid is working, but the Sony Browser seems not to be. Any ideas?

PS: I found I can manually enter "Avid MediaFiles/MXF/1" -- I just can't BROWSE to it. And, the .mxf files do go into "Avid MediaFiles/MXF/1".

Moreover, I can manually enter "Movies/AFF" -- I just can't BROWSE to it. And, the .aaf files do go into "AFF". This is nuts.

I can't comment on that stuff really, I've never used the ClipBrowser on a Mac - maybe someone else here can offer something?

Clip Browser for mac -not needed now that AMA is working great.

Use ama to link to the clips/volume.

take a look and edit instantly onto a sequence,

or use the consolidate command to copy the clips at the native resolution into the AvidMediaFiles folder aka Managed Media

Or use the transcode command to import the clips at an AVID DNx resolution of your choosing.