HPX 300 1080p pulldown

R

rtmst3k

Member
The HPX 300 specs indicate that it uses 2:3 pulldown in 1080p and a 2:3:3:2 in 1080pA (advanced mode, whatever that means)

From reading a lot of brochures on high-end HD cameras, I never see this pulldown used, or at least I haven't yet.

Is the use of "pulldown" considered a non-professional feature? I'm still learning what "pulldown" is, but it "sounds" like a manufacturer compromising the potential quality of the image due to a lower-cost sensor or other compromise made in the imaging system of the camera.

When I saw the spec that said the 300 was a 1080p "full raster" camera, for some reason, I thought this meant that pulldown wouldn't be required. I have an HMC 150 that is NOT a full-raster 1080 imager, and it uses pulldown.

I didn't expect the 300 to require any pulldown mechanism -- does this compromise the image quality? Do the Sony EX1/EX3 cameras also employ pulldown?

Thanks !!
Randy
 
Pull down is a standard method across all manufacturers that converts between 24 fps and 30 fps. I am surprised the others don't mention it.
 
Pulldown is only required when 24p (24 Hz) must be displayed or recorded in an 60 Hz stream. This is how 24 fps movies are shown on a conventional TV. Advanced pulldown is easy to reverse, so that the original 24p frames can be edited natively.

DVCPRO HD is an older codec and it must be recorded as 60 Hz (60i), so pulldown is required. In AVC-Intra mode, there is no pulldown in 1080; it's straight 24p.
 
HPX 300 2:3 pulldown

HPX 300 2:3 pulldown

David Jimerson said:
Pulldown is only required when 24p (24 Hz) must be displayed or recorded in an 60 Hz stream. This is how 24 fps movies are shown on a conventional TV. Advanced pulldown is easy to reverse, so that the original 24p frames can be edited natively.

DVCPRO HD is an older codec and it must be recorded as 60 Hz (60i), so pulldown is required. In AVC-Intra mode, there is no pulldown in 1080; it's straight 24p.
Click to expand...

So in AVC-Intra mode, there's no pulldown, it's straight 24p....so when I read in the HPX 300 specs that there is pulldown going on, that's when the 300 is recording in something else besides AVC-Intra. Correct?

I was just curious if pulldown affects image quality...for instance would a $50,000 studio HD camera be using pulldown like by $3000 HMC 150?

Thanks!!
Randy
 
You'll be recording 24p with pulldown in 1080 mode in DVCPRO HD (and also in any 480 mode, as well as 720 "P" mode -- but not 720 24pN).

It doesn't affect image quality at all. Any camera which shoots 1080/24p DVCPRO HD does the same thing, including the top-end P2HD cameras like the Varicams.
 
Randy, have you not read that wikipedia link? It explains things pretty clearly.

Pulldown generally refers to not a record method, but a rather ingenious way to translate all 24 fps footage into the 30 fps NTSC realm. Some people think of it as degradation. Others like that "film look" aspect it produces with video footage.

I don't have the 300's specs but wonder if it might be referring to the video output signal for monitoring or transfer.
 
The pulldown doesn't produce "film look." The frame rate does. All pulldown does is make it possible to record/view it in a standard 60i (or 60p in 720) stream.
 
Easy answer: DVCPro HD was designed for tape before it hit P2, so in 1080 mode it has to record 24p and 30p onto the 'tape' inside a 60i stream, which your NLE pulls out automatically with no quality loss. It simply duplicates the frames in a manner that your nle will ignore the duplicates.

In 720p mode, the same codec can record 720/24pN or 30pN which means Native, just storing 24 or 30 frames per second onto the tape/card, increasing shooting time. AVC-Intra is brand new and can shoot in "Native" 1080/24p, getting longer record times than its DVCPro HD counterpart (and looking a lot better thanks to the new codec's efficiency).
 
David Jimerson said:
The pulldown doesn't produce "film look." The frame rate does. All pulldown does is make it possible to record/view it in a standard 60i (or 60p in 720) stream.
Click to expand...

Yes you are absolutely correct, thanks for clearing that up, it didn't come out right. Must get more sleep before typing sometimes.
 
David Jimerson said:
The pulldown doesn't produce "film look." The frame rate does. All pulldown does is make it possible to record/view it in a standard 60i (or 60p in 720) stream.
Click to expand...
On another hand, pulldown is used to package "film rates" like 24/25/30 or even 16/18 into 50i/50p/60i/60p. So, in a way, pulldown does produce film look, indirectly. ;-)
 
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