View Full Version : Progressive or Interlaced


Hugo Ferreira
July 7th, 2007, 12:16 PM
Hi guys,

This is my first post here and i' m new to HDV. I work with DV cameras and avid for post. Now i started a small production company to make promotion videos, documentary, ENG, weddings and i want to try HDV. For now i'll buy a hdv camera and i' m kind of confused. I like a lot the JVC HD200, the professional look, all the manual controls and good image quality but i' m not sure about the 720p compatibility with CRT TVs and LCDs that are not progressive. Because i want to distribute my videos in DVD and to Broadcast and in Portugal (PAL), where i' m from, we unfortunately don't have HDTV and almost everyone has interlaced TVs. Do i have to worry about this issue? Another question i have is about NLE. I start using MAC and FCP for a couple of months and i' m very happy with it so i want to continue in the MAC world. I red in a lot of posts that the JVC HD200 and FCP don't combine very well. I like the Canon XL H1 but i prefer the picture from JVC. What do you think it's the best for my interests? And a last question, is there a big diference between 25p and 50p in image quality. Sorry about all the questions but itīs a big investment to do and at the end i don't want to be dissapointed.

Thanks in advance and congratulations for the great job you are doing here.

Glenn Chan
July 7th, 2007, 02:20 PM
TVs will display progressive images fine. It's not a problem. A CRT will display one half of the frame and then the other half.

Material shot on film is shown as 25p... 25 progressive frames a second. (Some is shot at 23.98 and speeded up to produce 25p).

2- Isn't the JVC footage compatible with FCP?

And a last question, is there a big diference between 25p and 50p in image quality.
For broadcast, you are limited to 25 frames per second. So the benefit of 50p is if you need slow motion.

David Heath
July 7th, 2007, 02:51 PM
I like a lot the JVC HD200, the professional look, all the manual controls and ........ we unfortunately don't have HDTV and almost everyone has interlaced TVs. Do i have to worry about this issue?
The nice thing about progressive (at least at 50p) is that it downconverts well, and a 576i/25 downconversion from a 720p/50 master should be great - depending on what you use for the conversion. A conversion from interlaced to progressive would be a far more difficult process. And you can still revisit the true HD master in the future.

I also agree about the HD200 - technical matters aside, it behaves far more like a professional camera than any other 1/3" camera ergonomically. Far easier to handhold, with controls well laid out, and much easier to add peripherals like a Firestore or camera light to than a Z1 or HVX200, say.
And a last question, is there a big diference between 25p and 50p in image quality.
Yes - but you have to define "image quality". In this case, 50p looks like "live action", 25p will be more "juddery". In that respect, it may be horses for courses - 50p is far better suited to live action, 25p is actively preferred by many for such as drama - "the film look".

David Heath
July 7th, 2007, 02:56 PM
For broadcast, you are limited to 25 frames per second. So the benefit of 50p is if you need slow motion.
For PAL, then yes, 25 frames per second, but interlace then means 50 fields per second, all unique temporally. That look can be derived from 50p (each progressive field gives one interlaced field) but not from 25p.