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-   -   25/50 frame rate setting, is it PAL? (https://www.dvinfo.net/forum/jvc-gy-hd-series-camera-systems/103736-25-50-frame-rate-setting-pal.html)

Scott Jaco September 17th, 2007 11:58 AM

25/50 frame rate setting, is it PAL?
 
I just got a phone call asking if I shoot in PAL, I told her no, that I shoot NTSC & HDV with my HD100U. I realize they do sell the HD100E version that shoots PAL but what about the 25/50 frame rate selections on my HD100U? What is the difference between that and PAL?

Sorry if it's a stupid question but I honestly would like to know what the difference is, and why they offer 25/50 frame rates on the US models?

David Knaggs September 17th, 2007 03:22 PM

Hi Scott.

PAL is Standard Definition. It has a frame size of 720 x 576 at 25 frames per second (which is 50 interlaced fields per second).

Your GY-HD100U should have the capability of shooting 720p25 and 576p50. Both of these are recorded with HDV compression (MPEG-2). But your 100U won't directly shoot PAL (576/50i).

Now, you COULD shoot in either of these with your 100U and then convert it into PAL (576/50i) using your NLE.

So you could tell that prospective client that you DO shoot PAL, provided they are after the progressive look (rather than the interlaced look).

For great results, shoot in 720p25, capture into your NLE and drag the clips into a DV PAL sequence. This will oversample 720 lines into 576 lines and look great. If final delivery is in 16:9 then you're good to go.

If a strict 4:3 delivery is required, you can simply increase the scale in the Motion tab (or the equivalent if you're using a PC-based NLE) until it's 4:3. It means the sides of the frame would be cropped (which you'd have to allow for while shooting) but you'll still get the 720 lines oversampled into 576 and so it'll still look terrific.

Scott Jaco September 18th, 2007 09:59 AM

Thanks. So it's not true PAL, but rather an HDV compressed frame rate.

Dennis Robinson September 18th, 2007 10:06 AM

Quote:

Originally Posted by David Knaggs (Post 745738)
Hi Scott.

For great results, shoot in 720p25, capture into your NLE and drag the clips into a DV PAL sequence. This will oversample 720 lines into 576 lines and look great. If final delivery is in 16:9 then you're good to go.

Hi David,
Is this the best way or an acceptable way to go. I shoot and capture HDV 720/25p and simply drag the clips into a DV timeline. Its easy enough to do but I wonder if the quality is ok like this? I work on TV commercials. In time I may need to get a capture card.
Dennis Robinson
Perth

David Knaggs September 18th, 2007 04:27 PM

Quote:

Originally Posted by Dennis Robinson (Post 746115)
Is this the best way or an acceptable way to go. I shoot and capture HDV 720/25p and simply drag the clips into a DV timeline. Its easy enough to do but I wonder if the quality is ok like this? I work on TV commercials. In time I may need to get a capture card.

Hi Dennis.

No, it's not the best way to go. I was just giving it as an example to show that, while a 100U model doesn't shoot PAL, a 100U + NLE = PAL.

If my final delivery is to DVD, I'll capture and edit natively, i.e. in an HDV 720p25 sequence and then output directly through Compressor to encode the DVD assets.

I've only shot commercials in PAL (576i) but, if I were to shoot a commercial tomorrow in HDV 720p25, I'd probably do the workflow this way:

1/ Capture the footage natively and then convert the footage to uncompressed and work in an uncompressed sequence all the way.

2/ Export as a self-contained uncompressed Quicktime movie to a portable hard drive.

3/ Take the hard drive to a post-house and get them to output the commercial to both Digital Betacam tape and HDCAM tape. You would really need to check yourself for specific delivery requirements in each case, but as our four major networks broadcast in both SD and HD now, I'm guessing that DigiBeta for SD and HDCAM for HD would be pretty safe options for delivery in most cases.

Of course, if you had a GY-HD251, you could even bypass the HDV compression by capturing live directly from the HD-SDI port into ProRes (with a capture card and on-set computer) or even uncompressed. (With a 101/111/201 you can get an uncompressed analog signal through the component outputs which would first require being put through an Analog-to-Digital converter before you could work with it.)

Then (in my opinion) you'd really be approaching the very highest quality with your camera and workflow for your commercials.

Giroud Francois September 19th, 2007 03:29 PM

unfortunately, PAL and NTSC says nothing about the size and frame rate of picture.
They are just a way to code color in a video signal.
To cut corner, most of people reference PAL to 720x576x50 and NTSC to 720x480x60 as we know for a long time from TV.
Since the computer age and digital video, this is not more a valid shortcut.
you better to speak in term of color space, resolution and frame rate.

basically if you are able to shoot at 50i or 25p and give a resolution that is 720x576 or 1280x720 or 1920x1080, you can say yes, you are pal compatible.


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