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-   Sony HVR-V1 / HDR-FX7 (https://www.dvinfo.net/forum/sony-hvr-v1-hdr-fx7/)
-   -   The option of V1 720p (https://www.dvinfo.net/forum/sony-hvr-v1-hdr-fx7/89731-option-v1-720p.html)

Steve Mullen March 25th, 2007 01:48 PM

Quote:

Originally Posted by John Bosco Jr. (Post 647946)
Someone correct me if I'm wrong, but I thought the V1 goes through a resolution converter before output to HDMI and component. So that would mean that although the camera scans 1920 x 1080p through horizontal pixel shift, the best achievable resolution at output after conversion is 1440 x 1080i, probably upsampled to 1920 x 1080i 60, not 1080p 60.

Pixel-shift isn't being used. V and H interpolation of all three colors is.

The HDMI chip gets only 1440 from the EIP which is then down-scaled to 1280. I'll bet the HDMI chip simply up-scales each field from 540 to 720. Presto -- 1440x1080i to 1280x720p. The FIELD rate becomes the FRAME rate.

Thomas Smet March 25th, 2007 06:44 PM

I think there is a huge difference between 576p and 720p. While the vertical resolution may not be that much higher the horizontal gets jumped from 720 up to 1280 which is a lot of extra horizontal detail. Sadly widescreen SD is still limited to 720 pixels (or 768 pixels for full PAL specs). This means widescreen SD ends up having to deal with the same anamorphic softened pixels as 1440 HD is compared to true 1920 HD.

The reason why a lot of 720p shot material looks pretty close to 720x576p material is because most 720p broadcasts are shot with DVCPROHD which only uses 960x720 pixels which is only slightly higher then 720x576p. A high quality camera shooting a nice detailed 1280x720 image will have a lot more horizontal detail (almost double) then 576p could ever have.

Stephen Armour March 25th, 2007 08:45 PM

Quote:

Originally Posted by Bob Grant (Post 647891)
I can see nothing wrong with the idea at all.
First though you'd need to consider what you'll use to backup your data, HDDs aren't the best for long term data storage. Any IT solution would work though.
Secondly keep in mind that it seems you'll need to blank the first 4 lines of vision due to Sony putting some oddball bits of data in there. This can be a bit of pain and can slip past you if you're not careful. Most 16:9 TVs will blank those lines but if it's broadcast in letterboxed SD those lines are very much visible. The question that remains though is should you also blank the bottom 4 lines as well to keep things even. Don't know the answer to that one.

I guess I missed something here. Didn't Sony just put out a fix on that oddball data prob on the first 4 scan lines? Don't the newer cam's have that already blanked now? Anybody have info on that?

Plus, is the HDMi port outputting 1920x1080i then? The Cineform codec handles the progressive conversion, so what's the catch, or is there one?

As to long-term storage, that has always been a moving target anyway, so we'll just HDD the productions for now, then when the larger capacity disks hit the market in a bit, we'll dup our backups onto that format as well to get us down the road. Hitachi's new 1TB drives will hold plenty, and it looks like they are very reasonably priced.

Steve Mullen March 25th, 2007 09:52 PM

Quote:

Originally Posted by Stephen Armour (Post 648334)
Plus, is the HDMi port outputting 1920x1080i then?

Good question!

If it is 1920x1080:

Is it up-scaling 1440x1080 to 1920x1080?

Or, is it getting a direct feed from the EIP?

I suspect the first.

But, if it gets 1920x1080, then the 720p would be a direct down-scale.

John Bosco Jr. March 26th, 2007 01:52 AM

Quote:

Originally Posted by Steve Mullen (Post 648366)
Good question!

If it is 1920x1080:

Is it up-scaling 1440x1080 to 1920x1080?

Or, is it getting a direct feed from the EIP?

I suspect the first.

But, if it gets 1920x1080, then the 720p would be a direct down-scale.

I now believe that the V1U's 1440 x 1080i HDMI output can be upsampled to 1920 x 1080i (most likely scenario) or downsampled to 1280 x 720p depending on the capabilities of the monitor or TV used. I'm unfamiliar with Black Magic's intensity card, but I imagine you can set to capture either interlace or progressive. If anyone has newer information, I would be most interested to know. Anyway, it is important to note that V1 outputs a 4:2:2 high definition signal via HDMI or component, so it should bid well for keying and/or advance color correction.

Stephen Armour March 26th, 2007 09:16 AM

Quote:

Originally Posted by John Bosco Jr. (Post 648467)
I now believe that the V1U's 1440 x 1080i HDMI output can be upsampled to 1920 x 1080i (most likely scenario) or downsampled to 1280 x 720p depending on the capabilities of the monitor or TV used. I'm unfamiliar with Black Magic's intensity card, but I imagine you can set to capture either interlace or progressive. If anyone has newer information, I would be most interested to know. Anyway, it is important to note that V1 outputs a 4:2:2 high definition signal via HDMI or component, so it should bid well for keying and/or advance color correction.

It would seem that if the V1 can truly output what it appears it's outputting to HDMI, then our plan of utilizing the Intensity card for ingest and conversion to the Cineform codec for post is a winner. Even though we'll have other input to deal with (from the tiny A1), our main cam for this is still the V1, so the final production should look quite nice.

Maybe we'll get another V1 so we can use the sync capability for two cams...hmmm...

BTW, we really like the V1's layout and handling. This little cam looks like a true winner and seems to bode very well for those of us trying to do much with relatively little (non-profit children's production).

Now, if we can just figure out how to do all this when flying our Merlin, we'll be almost there. The crane and dolly are easy, but the Merlin is SO sensitive to anything, it'll take something new to make it usable under this scheme of things.


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