Jump to content

Should Varicam be called HD?


Guest Pete Wright

Recommended Posts

Guest Pete Wright

Varicam records 960x720 pixels, is 35% more compressed than DV. HD starts at 1280x720p and goes up.

 

DV is 720x480. Even $300 Samsung DV camcorder records this resolution. DV recorder section never records 25% less pixels horizontally - 540x480 pixels.

 

The Samsung camera section is naturally not good enough for the full DV format resolution, but the recorder is always full 720x480. Otherwise it would not be DV.

 

If Varicam recorder is incapable recording HD, is it really HD?

 

Pete

Link to comment
Share on other sites

Guest Pete Wright

Hi,

 

The camera head is 1280x720 pixels but it records only 960x720. So the recorded image is not full 720p HD, which is 1280x720.

 

Pete

Link to comment
Share on other sites

Guest Pete Wright

We have these comon resolutions:

 

720x480... NTSC SD, DV (interlaced and progresive)

 

720x576... PAL SD, DV (interlaced and progressive)

 

960x720... Varicam recorder section

 

1280x720... 720p HD = min. HD resolution, HDV1 (JVC developed)

 

1440x1080... interlaced: HDV2 (Sony developed), broadcast

 

1440x1080... progressive = F900 recorder section

 

1920x1080... progressive = F950

Link to comment
Share on other sites

With all due respect, I'm not so sure the recorder section does record 960x720. First of all, that's a 4:3 aspect ratio and the Varicam is 16:9 native; it's capable of doing 4:3 but you're just cropping a section out of the middle of the frame. Second of all, when you import Varicam footage into a NLE system in comes in at 1280x720. Thirdly, from Panasonic's own literature the total pixel area is 1370x744 with an effective area of 1280x720. Unless there's something I'm missing here--some bit of software that sqeezes 1280 pixels into 960 before putting it to tape--that puts the Varicam into HD territory.

 

Plus, if it's not HD why did all the monitors in video village cost three times as much to rent? :lol:

Link to comment
Share on other sites

Guest Pete Wright

This is something neither Panasonic nor Sony want to tell you. I read an article about it and also in another forum. Here's the summary.

 

Sony used for f900 modified Digi Beta transport. Digi Beta records 90 Mbps; F900 doubles the rate to 180 Mbps. The problem is that 1080p resolution is 6x higher than SD resolution, while the recorder bit rate is 2x higher. So Sony filters and downsamples the image to 1440x1080 pixels and 3:1:1. When it plays it back it's digitally stretched to 1980 and HDSDI is 4:2:2, so it is changed digitally to that. This upconversion is done to the lower quality image that was recorded. Sony's overall compression is about 4.5:1.

 

Panasonic took DVCPRO 50 transport and modified it to also double the bit rate, to 100 Mbps. To squeeze the HD stream onto the tape, the recorded image has to be reduced to 960x720p. Since Varicam records 60p all the time, at any speed setting, the compression is always about 6.5:1. This is needed to squeeze all the data into the tape. Then it is upconveet to 1280x720 pixels.

 

Calling Varicam recorder 1280x720 is similar to taking SD image, converting it to HD and calling it HD.

 

Pete

Link to comment
Share on other sites

Guest Pete Wright

Well, I got some in this forum, some in other forums.

 

Reading the manufacturer's catalog sheet will leave you in the blank.

 

Pete

Link to comment
Share on other sites

  • Premium Member
This upconversion is done to the lower quality image that was recorded.

 

What your saying is that the image that is recorded is a 1440x1080 image, but the image that is played back is a 1920x1080 image. That doesnt make much sense, because if thats true then the image being played back would be out of proportion, and would look stretched on your monitor. 1440x1080 is a 4:3 aspect ratio, 1920x1080 is a 16:9 aspect ration, I'm sure you know what a 4:3 image looks like on a widescreen TV.

 

I ran a few tests a couple weeks ago with an F900 and a capture card. The images that the computer captured were all 1920x1080. Those images were going directly from the F900 out to a computer, HDSDI out of a 901 into an AJA card that only captures still frames. That is the same image that gets recorded on tape.

 

Pete you should be very skeptical about what you read on forums. Do some research before you believe anything, don't believe anything until you see it with your own eyes. The best way to do this is running tests. By making claims that the Varicam is not really an HD camera, with only rumour, and no hard evidence you will be confusing and misinforming a lot of people who read this.

Link to comment
Share on other sites

Guest Pete Wright

Hi Elhanas,

 

You can read posts on this site and will learn about it. I think that David Mullen mentioned it at one point or another too.

 

You can get 1280 pixels, downconvert it to 960 pixels, then upconvert it to 1280 pixels. Naturally you lose resolution. If you started with native 960 and play it in 960, the image would be more accurate than the manipulated 1280 image.

 

The number of pixels on a CCD have nothing to do with recorded pixels. You don't always use the CCD native resolution. Canon XL2 is using 480 vertical pixels in both the 4:3 and the 16:9 modes. It is using 720 horizontal pixels in 4:3 and a lot more CCD pixels in 16:9, although it records 720 in both modes.

 

As to Varicam being HD? Well what people call standard definiton spans anything from VHS to 720x576 progressive. HD starts at 1280x720 progressive and extends to some 3840p or whatever. At some point this resolution is refered to Ultra High Definition.

 

If you look at the short band between PAL SD and 720p HD, Varicam is a little close to HD. If you look at the whole HD and SD spectrum, Varicam sits somewhere in between.

 

F900 is not 1920x1080 either, but it is still within this HD spectrum. Varicam is not.

 

HDV2 by Sony is also 16:9 and is using 1440x720 pixels.

 

Pete

Link to comment
Share on other sites

Guest Pete Wright

My absolutely last post for now; I only came back for the weekend; I have to be going.

 

I even read in another forum about some lawsuit that some camera was misrepresented by certain manufacturer in it's literature and ads.

 

So guys, you need to do your homework, just because it says everywhere HD and 720p and the CCD is native 720p, which means 1280x720 pixels, it does not mean that you're getting true HD.

 

It's that simple. Still the Varicam is an excellent camera.

 

Pete

Link to comment
Share on other sites

Pete,

 

You've hit on the crux of this issue: the Varicam is an excellent camera and, though I haven't personally shot with it, the F900 obviously produces a good image. If the image is good enough for your purposes, what's the point of arguing about whether it's nearly High Definition, or High Definition, or Ultra High Definition, or whatever? Agonizing about terminology does no one any good; arguing about image quality is another thing. And since you seem to be satisfied with the Varicam, why worry about it whether it's "really" high defintion? Once you do that its very easy to say that none of the HD cameras are really high def. when compared to scanned film.

 

Do you have some sort of scheme to produce a better image from the camera? If so, let's talk about that rather simple academic terminology.

Link to comment
Share on other sites

  • 2 weeks later...
  • 4 months later...
Panasonic took DVCPRO 50 transport and modified it to also double the bit rate, to 100 Mbps. To squeeze the HD stream onto the tape, the recorded image has to be reduced to 960x720p. Since Varicam records 60p all the time, at any speed setting, the compression is always about 6.5:1. This is needed to squeeze all the data into the tape. Then it is upconveet to 1280x720 pixels.

 

Calling Varicam recorder 1280x720 is similar to taking SD image, converting it to HD and calling it HD.

 

Pete

 

What is upconverted? The resolution on the TAPE is 960x720 at any frame rate. Coming out of the camera port is 1280x720.

 

Sounds like you should do a little more fact checking.

Link to comment
Share on other sites

  • 4 months later...
Hi Elhanas,

 

You can read posts on this site and will learn about it. I think that David Mullen mentioned it at one point or another too.

Pete

 

I am not sure if this info is correct, but the link could be what Pete also found. The Article is the one dated Feb 28th, 2005. Are these data right?

 

http://www.hdforindies.com/archivedarticle...rchived_article

 

maurizio

Link to comment
Share on other sites

  • 2 months later...
I am not sure if this info is correct, but the link could be what Pete also found. The Article is the one dated Feb 28th, 2005. Are these data right?

 

http://www.hdforindies.com/archivedarticle...rchived_article

 

maurizio

 

I'm not sure it is correct. Are they taking pixel shift into account?

 

<Addition: Just found this info...

960x720p 4:2:2 (Varicam)

1280x720p 4:2:0 (HDV-1)

1440x1080i 3:1:1 (HDCAM)

1440x1080psf 3:1:1 (HDCAM)

1440x1080i 4:2:0 (HDV-2)

1920x1080p 4:2:2 (HDCAM-SR)

1920x1080p 4:4:4 (HDCAM-SR)>

Edited by Simon Wyndham
Link to comment
Share on other sites

  • 5 years later...

Hengky,

 

At the time when the tape varicam's came out they were the best and stil are and who to say that the varicam is not full HD both 1080 and 720 are FULL HD. I have the Panasonic HPX 300 (Full raster 1920x1080 4:2:2) and are you going to tell me that's not full HD cause it is and does about 95% of all the things that the varicam does. And Pete it would help if you put a link seriously come on bro back up what your going to say with some hard facts and proof. You talk talk talk and have nothing to show it and that can be miss leading to new people. To me FULL HD will always be FILM cause I am the last genx to maybe even load film all every single panavision and arri camera you can think of. But i love the new Arri Alexia for sure but it's just another tool as we all like to say. And as always dave is correct about 720 being HDTV.:) Dave if you ever need a 2nd AC please let me know it would be a honor to work with you.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...