Can anyone explain 720p30N to me? at DVinfo.net

Bill Edmunds · July 23rd, 2006, 05:41 AM

I know it records only "active" frames... what does that mean, exactly? That any pixels that are not moving are essentially recorded as stills?

Kevin Dooley · July 23rd, 2006, 06:59 AM

No, it means that it only records 30 frames per second, instead of embedding the 30p stream into 60p, thus using less P2/disk space (it'll run 50 Mb/s instead of 100 Mb/s)

Bill Edmunds · July 23rd, 2006, 08:19 AM

Quote:

Originally Posted by Kevin Dooley

No, it means that it only records 30 frames per second, instead of embedding the 30p stream into 60p, thus using less P2/disk space (it'll run 50 Mb/s instead of 100 Mb/s)

What does it look like as far as the image is concerned? Does it have more judder than "regular" 720p30?

David Saraceno · July 23rd, 2006, 10:44 AM

"judder" refers to what?

Bill Edmunds · July 23rd, 2006, 11:39 AM

Quote:

Originally Posted by David Saraceno

"judder" refers to what?

Judder is the defacto word of the moment that refers to the "strobing" look of progressive video. In other words, is 720p30N less "smooth" than non-native 720p30?

Kevin Dooley · July 23rd, 2006, 12:23 PM

I'm still waiting on my camera, so I can't verify 100%, but I can't see any reason why it should look any different than a 30p stream embedded into a 60p. It is still 30 progressive frames per second either way....

And progressive video at less than 60 frames per second is only stroby or juddery because it was shot improperly... Most movies are mastered and mostly shot (except for FX shots) at 24 fps... so it's merely a matter of know how to shoot with a lower temporal rate...

Robert Lane · July 23rd, 2006, 12:30 PM

Bill,

There is no difference in how motion looks between 30P and PN, it is still 30 frames per second. The PN mode is simply an electronic method for saving space on P2 cards.

Slower rates/shutter speeds will render more more motion blur or "judder" as you call it. Faster shutter speeds will be more fluid and smooth.

The best way to answer your question is to test various frame rates for yourself and see how they look on an external monitor. Don't rely on what you see on the flip-out LCD or EVF, you'll get a much better feel for what motion looks like with any external monitor.

If fluid motion is important to you then use either 30P or 60P; if you want things to look more like film or have a cinematic feel then the de-facto standard to help create that look is 24P.

There is no right or wrong way to shoot anything - it all depends on what YOU want for a specific look or feel to your movies.

Bill Edmunds · July 23rd, 2006, 01:43 PM

Quote:

Originally Posted by Robert Lane

Bill,

There is no difference in how motion looks between 30P and PN, it is still 30 frames per second. The PN mode is simply an electronic method for saving space on P2 cards.

Slower rates/shutter speeds will render more more motion blur or "judder" as you call it. Faster shutter speeds will be more fluid and smooth.

The best way to answer your question is to test various frame rates for yourself and see how they look on an external monitor. Don't rely on what you see on the flip-out LCD or EVF, you'll get a much better feel for what motion looks like with any external monitor.

If fluid motion is important to you then use either 30P or 60P; if you want things to look more like film or have a cinematic feel then the de-facto standard to help create that look is 24P.

There is no right or wrong way to shoot anything - it all depends on what YOU want for a specific look or feel to your movies.

Thanks for the info. Given that you can fit twice the data in 30pn, why would you use 30p instead of it? What's the advantage?

Kevin Dooley · July 23rd, 2006, 03:02 PM

The only thing I can think of is that it would fit into a tape-based work flow better, in case you're using the HVX as a b-cam to a varicam or something along those lines...

Also the camera doesn't record audio if you use an off speed in 30/24pN mode. So you'd have to record regular 30/24p mode if you want to under or over crank and you need audio...

Barry Green · July 23rd, 2006, 11:04 PM

Quote:

Originally Posted by Bill Edmunds

Thanks for the info. Given that you can fit twice the data in 30pn, why would you use 30p instead of it? What's the advantage?

It streams out the firewire port. 30pN doesn't. So if you want to pipe the signal out the firewire port to record on a FireStore or a DVCPRO-HD tape deck or record on Serious Magic DVC Rack or directly into Avid or FCP or EDIUS, you'd have to use the 30P mode, not the 30pN mode.

Bill Pryor · July 24th, 2006, 10:03 AM

This is a little off topic, but how much record time do you get on a 4 gig card when shooting 720pn?

Barry Green · July 24th, 2006, 11:42 AM

10 minutes on a 4 gb card

Bill Pryor · July 24th, 2006, 12:10 PM

Thanks, Barry...another question here--Pardon my newbie questions, but I have not considered P2 until recently because of some work flow issues, but there are some things about the camera that might make it a better tool for me for certain things. However, I'm unclear on how to transfer the card contents to a laptop (iBook) or a drive without using the camera. I found in the Panasonic material something about a P2 reader that goes into a laptop, but only a non-Mac. Is there some kind of reader that would work with a Mac, or are we stuck in the Apple world with transferring only from the camera, or having to buy the pricey portable storage drive? If I had an easy and inexpensive way to dump files from a card reader to a portable hard drive or iBook, I might could make this work. I'm considering a new camera for personal documentary work, but want it to be the same format as any new camera we might buy as a business in a year or so (I've been looking at XDCAM HD cameras, but I'm not sold on going down from a 2/3" chip to a 1/2" chip camera for business work--the 2/3" chip Panasonic HD cam that will be introduced next year would be better for us...and if I start liking that, I would like to have bought an HVX200 for personal stuff rather than a Z1...but I need a way to transfer P2 cards on a short crew location shoot).

Barry Green · July 24th, 2006, 04:18 PM

There are several ways to offload in the field; for the mac, perhaps the most convenient is the G4 powerbook. It has a PCMCIA slot so you can just plug the card straight into it and drag 'n' drop the contents.

For the macbook pro, which doesn't have a PCMCIA slot, there's an adapter coming in the next few weeks (hopefully) that will give it the same capabilities.

For an earlier ibook that doesn't have a slot at all, you'd need a different tactic. Obviously using the camera as a reader can work, but is less than ideal (since in that scenario you can't be shooting while a card is offloading). So I'd recommend one of four potential options:

1) get a P2 Store. This device will offload all by itself (including verifying and formatting), which is handy. But it also acts as a pass-thru slot reader, letting your ibook directly read the cards through the P2 Store (connected via a USB port). If you were thinking about getting a P2 Store anyway, or were on the fence, this might help justify the decision more.

2) you can get one of Panasonic's slot reader devices. Although, at $2500, this is hardly the option I'd recommend first.

3) (and this is crazy, but bear with me): get a cheap PC laptop. Instead of spending money on adapters and P2 Stores, you can buy a cheapo low-grade "Office Depot Holiday Weekend Special" laptop for maybe $400 or $500, which will have all the capability you need to offload cards. Offload to an external bus-powered firewire drive (formatted FAT32) and you can then plug that drive directly into your Mac. PC laptops with PCMCIA slots are cheap and plentifully available. Doesn't mean you have to "convert" to being a Windows user, it just means you're using $400 worth of hardware to do the same job that a $1600 P2 Store does.

4) consider picking up a used G4 powerbook. Now that the intel macbooks are out, you can expect that G4 powerbooks are going to be dropping in price and becoming more available on ebay etc., so for those who really want to stick with just the mac platform this might be an option that makes sense.

For the most flexibility I'd recommend option 3, or maybe 4. I imagine there are reasons one would want option 2) but it doesn't fit my workflow. I'm highly tempted by option 1); I know people gripe about the cost of the p2 store in relation to its capacity, but frankly it sure sounds like everyone who has one, loves it. So I'm tempted to go with a new MBP and a P2 Store, and use it as a P2 Store most of the time, and as a slot reader when necessary.

Hopefully others will chime in with their workflow suggestions too!

Bill Pryor · July 24th, 2006, 07:22 PM

Interesting suggestions. I'm not inclined to trust my footage to a cheapo PC laptop. It seems the P2 Store is the best thing, but it's way overpiced, and B&H says they're not available yet, at least they don't have them in stock.
Shooting 720pn would get about 20minutes, I understand, per 8-gig card. The 60 gig P2 Store, then, would only hold a bit over 140 minutes. The faq about the P2 store implies it only works with Windows, doesn't mention Mac.

I finally got to see the HVX camera in person and liked it more that I thought I would. And, since Panasonic is coming out with the 2/3" chip model next year, I was starting to think we could go for it as our main camera, and get the HVX as the little camera now. But I can't see my way into the P2 workflow. Damn. For awhile there I thought I had something working.

July 23rd, 2006, 05:41 AM	#1
Bill Edmunds Major Player Join Date: Aug 2003 Location: Conway, NH Posts: 574	Can anyone explain 720p30N to me? I know it records only "active" frames... what does that mean, exactly? That any pixels that are not moving are essentially recorded as stills?

July 23rd, 2006, 06:59 AM	#2
Kevin Dooley Major Player Join Date: Dec 2003 Location: Fort Worth, TX Posts: 414	No, it means that it only records 30 frames per second, instead of embedding the 30p stream into 60p, thus using less P2/disk space (it'll run 50 Mb/s instead of 100 Mb/s) __________________ Kevin Dooley Media Director, Pantego Bible Church

July 23rd, 2006, 12:23 PM	#6
Kevin Dooley Major Player Join Date: Dec 2003 Location: Fort Worth, TX Posts: 414	I'm still waiting on my camera, so I can't verify 100%, but I can't see any reason why it should look any different than a 30p stream embedded into a 60p. It is still 30 progressive frames per second either way.... And progressive video at less than 60 frames per second is only stroby or juddery because it was shot improperly... Most movies are mastered and mostly shot (except for FX shots) at 24 fps... so it's merely a matter of know how to shoot with a lower temporal rate... __________________ Kevin Dooley Media Director, Pantego Bible Church

July 23rd, 2006, 03:02 PM	#9
Kevin Dooley Major Player Join Date: Dec 2003 Location: Fort Worth, TX Posts: 414	The only thing I can think of is that it would fit into a tape-based work flow better, in case you're using the HVX as a b-cam to a varicam or something along those lines... Also the camera doesn't record audio if you use an off speed in 30/24pN mode. So you'd have to record regular 30/24p mode if you want to under or over crank and you need audio... __________________ Kevin Dooley Media Director, Pantego Bible Church

July 23rd, 2006, 10:44 AM	#4
David Saraceno Major Player Join Date: Jan 2006 Location: Inland Northwest Posts: 490	"judder" refers to what?

July 23rd, 2006, 12:30 PM	#7
Robert Lane Go Go Godzilla Join Date: Nov 2004 Location: Scottsdale, AZ USA Posts: 2,823 Images: 15	Bill, There is no difference in how motion looks between 30P and PN, it is still 30 frames per second. The PN mode is simply an electronic method for saving space on P2 cards. Slower rates/shutter speeds will render more more motion blur or "judder" as you call it. Faster shutter speeds will be more fluid and smooth. The best way to answer your question is to test various frame rates for yourself and see how they look on an external monitor. Don't rely on what you see on the flip-out LCD or EVF, you'll get a much better feel for what motion looks like with any external monitor. If fluid motion is important to you then use either 30P or 60P; if you want things to look more like film or have a cinematic feel then the de-facto standard to help create that look is 24P. There is no right or wrong way to shoot anything - it all depends on what YOU want for a specific look or feel to your movies.

July 24th, 2006, 10:03 AM	#11
Bill Pryor Contributor Join Date: Jan 2003 Location: Kansas City, MO Posts: 4,449	This is a little off topic, but how much record time do you get on a 4 gig card when shooting 720pn?

July 24th, 2006, 11:42 AM	#12
Barry Green Barry Wan Kenobi Join Date: Jul 2003 Location: North Carolina Posts: 3,863	10 minutes on a 4 gb card

July 24th, 2006, 12:10 PM	#13
Bill Pryor Contributor Join Date: Jan 2003 Location: Kansas City, MO Posts: 4,449	Thanks, Barry...another question here--Pardon my newbie questions, but I have not considered P2 until recently because of some work flow issues, but there are some things about the camera that might make it a better tool for me for certain things. However, I'm unclear on how to transfer the card contents to a laptop (iBook) or a drive without using the camera. I found in the Panasonic material something about a P2 reader that goes into a laptop, but only a non-Mac. Is there some kind of reader that would work with a Mac, or are we stuck in the Apple world with transferring only from the camera, or having to buy the pricey portable storage drive? If I had an easy and inexpensive way to dump files from a card reader to a portable hard drive or iBook, I might could make this work. I'm considering a new camera for personal documentary work, but want it to be the same format as any new camera we might buy as a business in a year or so (I've been looking at XDCAM HD cameras, but I'm not sold on going down from a 2/3" chip to a 1/2" chip camera for business work--the 2/3" chip Panasonic HD cam that will be introduced next year would be better for us...and if I start liking that, I would like to have bought an HVX200 for personal stuff rather than a Z1...but I need a way to transfer P2 cards on a short crew location shoot).

July 24th, 2006, 04:18 PM	#14
Barry Green Barry Wan Kenobi Join Date: Jul 2003 Location: North Carolina Posts: 3,863	There are several ways to offload in the field; for the mac, perhaps the most convenient is the G4 powerbook. It has a PCMCIA slot so you can just plug the card straight into it and drag 'n' drop the contents. For the macbook pro, which doesn't have a PCMCIA slot, there's an adapter coming in the next few weeks (hopefully) that will give it the same capabilities. For an earlier ibook that doesn't have a slot at all, you'd need a different tactic. Obviously using the camera as a reader can work, but is less than ideal (since in that scenario you can't be shooting while a card is offloading). So I'd recommend one of four potential options: 1) get a P2 Store. This device will offload all by itself (including verifying and formatting), which is handy. But it also acts as a pass-thru slot reader, letting your ibook directly read the cards through the P2 Store (connected via a USB port). If you were thinking about getting a P2 Store anyway, or were on the fence, this might help justify the decision more. 2) you can get one of Panasonic's slot reader devices. Although, at $2500, this is hardly the option I'd recommend first. 3) (and this is crazy, but bear with me): get a cheap PC laptop. Instead of spending money on adapters and P2 Stores, you can buy a cheapo low-grade "Office Depot Holiday Weekend Special" laptop for maybe $400 or $500, which will have all the capability you need to offload cards. Offload to an external bus-powered firewire drive (formatted FAT32) and you can then plug that drive directly into your Mac. PC laptops with PCMCIA slots are cheap and plentifully available. Doesn't mean you have to "convert" to being a Windows user, it just means you're using $400 worth of hardware to do the same job that a $1600 P2 Store does. 4) consider picking up a used G4 powerbook. Now that the intel macbooks are out, you can expect that G4 powerbooks are going to be dropping in price and becoming more available on ebay etc., so for those who really want to stick with just the mac platform this might be an option that makes sense. For the most flexibility I'd recommend option 3, or maybe 4. I imagine there are reasons one would want option 2) but it doesn't fit my workflow. I'm highly tempted by option 1); I know people gripe about the cost of the p2 store in relation to its capacity, but frankly it sure sounds like everyone who has one, loves it. So I'm tempted to go with a new MBP and a P2 Store, and use it as a P2 Store most of the time, and as a slot reader when necessary. Hopefully others will chime in with their workflow suggestions too!

July 24th, 2006, 07:22 PM	#15
Bill Pryor Contributor Join Date: Jan 2003 Location: Kansas City, MO Posts: 4,449	Interesting suggestions. I'm not inclined to trust my footage to a cheapo PC laptop. It seems the P2 Store is the best thing, but it's way overpiced, and B&H says they're not available yet, at least they don't have them in stock. Shooting 720pn would get about 20minutes, I understand, per 8-gig card. The 60 gig P2 Store, then, would only hold a bit over 140 minutes. The faq about the P2 store implies it only works with Windows, doesn't mention Mac. I finally got to see the HVX camera in person and liked it more that I thought I would. And, since Panasonic is coming out with the 2/3" chip model next year, I was starting to think we could go for it as our main camera, and get the HVX as the little camera now. But I can't see my way into the P2 workflow. Damn. For awhile there I thought I had something working.