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Home: Video University Forums: HDV:
Is V1U true 1080p or not

bladeronner
Enthusiast

Jan 17, 2007, 4:53 PM

Post #1 of 9 (1362 views)
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Is V1U true 1080p or not	Can't Post

i just finished watching Sony's promo DVD for the HV1 and it keeps referring to the camera as shooting in full 1080i. There's a "progressive" chapter that talks about the camera shooting in 24p or 30p scan mode in the HDV 60i format. What exactly does that mean? It sounds like double talk. And all the writing I see in the menus and the camera say 1080i. Is it true 1080p or not?

Thanks,
Ron
Ron Dawson
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Tim
Enthusiast

Jan 17, 2007, 5:16 PM

Post #2 of 9 (1355 views)
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Re: [bladeronner] Is V1U true 1080p or not [In reply to]	Can't Post

This camera will not shoot in 1080P. 1080i only. They may be referring to the field rate and not the frame rate which would be more accurate in an interlaced device.

VU Minnesota Crew

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RustyB
Veteran

Jan 17, 2007, 5:25 PM

Post #3 of 9 (1354 views)
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Re: [bladeronner] Is V1U true 1080p or not [In reply to]	Can't Post

http://bssc.sel.sony.com/...V1U/progressive.html

Quote

The signals generated by the 3 ClearVid CMOS Sensor are processed in the progressive domain as 1920 x 1080p signals, allowing high-resolution progressive footage to be captured.............

..........The 24p scan signals are recorded on tape as 60i signals through means of 2:3 pull-down. Similarly, a 30p scan signal is recorded as a 60i signal by dividing each frame into two fields. This allows your 24p and 30p scan footage to be played back or fed to an editing suite using the thousands of Sony HDV equipment already in use throughout the world.

faith poison films
it's better than nothing

bladeronner
Enthusiast

Jan 17, 2007, 5:39 PM

Post #4 of 9 (1350 views)
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Re: [Tim] Is V1U true 1080p or not [In reply to]	Can't Post

In Reply To

This camera will not shoot in 1080P. 1080i only. They may be referring to the field rate and not the frame rate which would be more accurate in an interlaced device.

So, does this mean the V1U is not capturing full frames? If I want a true progressive HD camera, is the JVC then my best bet?

Thanks,
Ron
Ron Dawson
Cinematic Studios Inc.
The blog
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Tim
Enthusiast

Jan 17, 2007, 5:51 PM

Post #5 of 9 (1347 views)
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Re: [bladeronner] Is V1U true 1080p or not [In reply to]	Can't Post

I think that the JVC shoots in 720p. So you'd get the sequential recording that you want but at a loss of resolution, that is if your looking at the HD250. Personally from the HD broadcasts that I've see 1080i is better. Football on Fox is not as crisp as the broadcasts on CBS and they us 720p and 1080i respectively. My opinion though.

VU Minnesota Crew

Well, I'm the best there is. Plain and simple, when I wake up in the morning I piss excellence.

videobear
Veteran

Jan 17, 2007, 6:16 PM

Post #6 of 9 (1345 views)
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Re: [Tim] Is V1U true 1080p or not [In reply to]	Can't Post

I don't think that's correct, Tim. According to my info, the V1u will shoot in 1080 60i, 1080 24p, and 1080 30p. The last two are "true" progressive modes, as opposed to Sony's earlier Cineframe modes.

Regards,
Doug Graham
Panda Productions

RustyB
Veteran

Jan 17, 2007, 6:39 PM

Post #7 of 9 (1341 views)
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Re: [bladeronner] Is V1U true 1080p or not [In reply to]	Can't Post

In Reply To

This camera will not shoot in 1080P. 1080i only. They may be referring to the field rate and not the frame rate which would be more accurate in an interlaced device.

So, does this mean the V1U is not capturing full frames? If I want a true progressive HD camera, is the JVC then my best bet?

Thanks,
Ron

I think the confusion here is the difference between "shooting" and "recording". I think the JVC actually records 720/24p HDV to tape. The Sony, only records in 60i HDV (or 60i DV). However, the V1U SHOOTS in 1080/24p...but in order to record it, it does the pulldown to 60i...it's up to your NLE to re-assemble the 24p, and remove the pulldown, returning it to 1080/24p. This keeps all of the Sony HDV gear standard. You could shoot 24p with the V1U, and capture it with a HC3, for example.

faith poison films
it's better than nothing

(This post was edited by RustyB on Jan 17, 2007, 6:40 PM)

Postal Boy
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Jan 18, 2007, 2:12 PM

Post #8 of 9 (1287 views)
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Re: [RustyB] Is V1U true 1080p or not [In reply to]	Can't Post

This sounds like the same method used by the DVX panny to record. It shoots progressive, but has to record interlaced, thus using the "pulldown" method to mix fields.

-Postal

dvpro
User

Jan 20, 2007, 3:43 PM

Post #9 of 9 (1240 views)
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Re: [bladeronner] Is V1U true 1080p or not [In reply to]	Can't Post

CMOS chips grab a full frame at every pass, where the older CCD chips took two separate fields and combined them to create a frame with most camcorders. Of course, my FX-7 doesn't offer progressive scan, so that full frame capture is electronically reworked to be two different fields like we are used to for interlaced video.

With say a Sony VX-2100 or PD-150, if you drop shutter to 1/30, you only get half-resolution recorded to tape. With the V1U, you would get 30 "full frames" recorded (as 60i). As Sony puts it - "a 30p scan signal is recorded as a 60i signal by dividing each frame into two fields". See here -

http://bssc.sel.sony.com/...V1U/progressive.html

So the camera does NOT actually record a 24p or 30p signal to the tape, but uses pull-down for 24p and splits 30p into two fields, and always records 60i to tape for compatibility with any existing HDV application.

To answer your question, the camera does shoot 1080p, because when shooting in 30p mode for instance, the playback will not have "interlacing" - the 60i playback should be showing you 30 "full frames" in essence (the two fields will not have any motion between them, they will make up one full 30p frame).

I hope this makes sense. When shooting 1080i, the two-fields making up a frame will differ when motion is being captured. There is a TIME difference between when the two fields were captured. When shooting 1080p, the two fields making up a frame were taken at the SAME MOMENT IN TIME, so though it's recorded as 60i, it should "look" like 30p.

That's my understanding anyway ;-)

Jeff Pulera
Digital Vision