1080i

T

theos

Veteran
I am still unclear about the i in 1080i. As I understand 1080 is a progressive mode and not interlaced . . . why do we still call it 1080i and not p?
 
You have the option to "Shoot" (the image sensor bit) 1080 either interlaced or Progressive. However you can only "Record" (the P2 card bit) 1080 interlaced, becuse that's what the signal standard is.

Shooting Progressive will be recorded as interlaced, but it will look fully progressive on a monitor as the fields will be simultaniuos.

- Mikko
 
Just to be clear... the 1080P is recorded to P2 in the same way as 24P was recroded to tape on the DVX100. You then need to remove the redundant frames in your NLE.
 
correction - not redundant frames - you need to remove the pulldown which is actually separating and recombing interlaced frames in the order dictated by the pulldown 2:3 or 2:3:3:2
 
correction to the correction.

Shooting 24p in 1080i mode will leave redundent, repeated, fields. - a good 12 of them per seccond to be exact.

- Mikko
 
It was my understanding that shooting 24pA removed the redundant frames..... Am I wrong?

in fcp (left that out)
 
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HDkilledFILM. said:
It was my understanding that shooting 24pA removed the redundant frames..... Am I wrong?

in fcp (left that out)
Click to expand...


Ahooting 24pA adds the redundant frames to make it a 29.97 stream to make it NTSC compliant. You then remove it while capturing or after with your NLE after.
 
HDkilledFILM. said:
It was my understanding that shooting 24pA removed the redundant frames..... Am I wrong?

in fcp (left that out)
Click to expand...
FCP, currently, cannot remove the 24PA pulldown from 1080i footage. Guess we'll have to wait for the annual NAB announcement from Apple to see if they'll suport it.
 
I found this on another forum. Adam Wilt came up with this solution for now:

He said that when you select the F1-only mode in CineTools' Remove 2:3 Pulldown, it effectively does a 2:3:3:2 pulldown removal, not a 2:3 pulldown removal.

I tested it with footage from the HVX as well as test clips I made in After Effects. This method with CineTools correctly transfered both even and odd fields, despite being called F1-only. Just to be sure, I compared still frames from the original and the CineTools processed footage using a difference blending mode in Photoshop and they were identical for a set of A,B,C, and D frames from the 2:3:3:2 cadence. No evidence of recompression either.

The one downside is that CineTools produces a file that the Finder shows to be 640x360, but both QT Player and FCP show to be
1920x1080. It's a minor annoyance.

After Effects still treats the file produced by CineTools like it is really 640x360, which makes it unusable there due to pixelation when you scale it up. Fortunately AE's Interpret Footage command does correctly remove 24pA pulldown, so the original 1080i24pA files from the HVX can be used in AE directly without having to use CineTools.​
 
It was my inquiry that received Adam's helpful answer and which I tested as described above.

At the Apple/Pana event in SF yesterday, they demonstrated in FCP using a "Cinema Tools Reverse Telecine" command in the Tools menu to remove advanced pulldown from a 1080i24pA clip open in the FCP Viewer. It was nice to see not having to leave FCP and open the clip in CineTools.

Be warned that it does unfortunately still result in a clip media file that the Finder and Quicktime identify as 640x360 pixels. Hopefully they'll fix this and add HD pulldown removal in the FCP6 app itself.

Note also that this inter-application integration only works in FCP 5.04 with CineTools 3.03 and (I believe) the recent Pro App Support updates installed. I had to delete my prefs and delete/reinstall both FCP & CineTools and apply the most recent updates to get this FCP menu item to appear for 1080i24pA clips.

The command in FCP also doesn't ask for which frame in the 24pA cadence the clip starts on. Meaning that it asumes it starts on an "A" frame. I *think* but haven't tested that the HVX starts all 1080i24pA clips on A frames, so the FCP command "gets it right." But if you have trimmed your clip in FCP and then run the remove telecine command, there's no telling if FCP/CineTools is going to get the cadence start frame right. So the best workflow probably means running the Remove Telecine command right after media ingest and before any trimming/subclipping gets done.

Also note that this command is destructive, in that it overwrites the 1080i24pA file with the 1080P (23.98) clip. So it seems prudent to me to make archives of your P2 "camera tape" files BEFORE removing pulldown.
 
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Thanks John. I apologize for not remembering your name when I quoted you. When I saw the original thread on the other forum I copy pasted into a text document and saved it for my own purposes.
 
John Pilgrim said:
It was my inquiry that received Adam's helpful answer and which I tested as described above.

At the Apple/Pana event in SF yesterday, they demonstrated in FCP using a "Cinema Tools Reverse Telecine" command in the Tools menu to remove advanced pulldown from a 1080i24pA clip open in the FCP Viewer. It was nice to see not having to leave FCP and open the clip in CineTools.

Be warned that it does unfortunately still result in a clip media file that the Finder and Quicktime identify as 640x360 pixels. Hopefully they'll fix this and add HD pulldown removal in the FCP6 app itself.

Note also that this inter-application integration only works in FCP 5.04 with CineTools 3.03 and (I believe) the recent Pro App Support updates installed. I had to delete my prefs and delete/reinstall both FCP & CineTools and apply the most recent updates to get this FCP menu item to appear for 1080i24pA clips.

The command in FCP also doesn't ask for which frame in the 24pA cadence the clip starts on. Meaning that it asumes it starts on an "A" frame. I *think* but haven't tested that the HVX starts all 1080i24pA clips on A frames, so the FCP command "gets it right." But if you have trimmed your clip in FCP and then run the remove telecine command, there's no telling if FCP/CineTools is going to get the cadence start frame right. So the best workflow probably means running the Remove Telecine command right after media ingest and before any trimming/subclipping gets done.

Also note that this command is destructive, in that it overwrites the 1080i24pA file with the 1080P (23.98) clip. So it seems prudent to me to make archives of your P2 "camera tape" files BEFORE removing pulldown.
Click to expand...

I am going to try that.
I have been trying to figure out the best way to deliver
stock footage. Say I do all of the above. The end result
needs to be a 1920x1080p QT clip saved as a 30fps
PhotoJpeg compressed clip. ArtBeats delivers clips this way.
Or should I just shoot 30p and forget about 24p or 24pA??
Any suggestions??
 
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