How do I know it is 16-9?

A forum to share ideas and opinions on the equipment and technical aspects of film, video and AV making.
Post Reply
User avatar
Dave Watterson
Posts: 1872
Joined: Sun Jan 28, 2007 11:11 pm
Location: Bath, England
Contact:

How do I know it is 16-9?

Post by Dave Watterson »

This may seem to be a silly question, but ...

I have been preparing tapes of this year's British entries for UNICA. All of them are in the 16:9 format. All have the proper leader on them, the subtitles are in place ... now I am downloading from computer to MiniDV cassettes.

But my camcorder is 4:3. Is there a risk that the camcorder will remove the "flag" in the data which tells video systems to use 1.422 pixels instead of square ones?

I have found that at every stage in the chain from original shoot, through edit and on to output on tape or DVD there is a risk that this information gets lost. When screening, that can mean that automatic projectors do not get reliable clues about the format. The result can be like UNICA in Tunisia, when many movies were projected in the wrong format - and the technicians seemed to have no way of overriding the automatics (!)


When I download a film onto the camcorder, open a new project in my editing program and upload that film again, Premiere tells me it is still in the 1.422 pixel shape. When I save that re-imported file, then open it in Windows Media Player it appears in the correct 16-9 format.

OK I am being a little paranoid ... but these are other peoples' films and I want to be certain they are shown to the best possible advantage.

Can anyone suggest other tests?

-Dave
chrisk

Re: How do I know it is 16-9?

Post by chrisk »

Hi Dave,
I looked at this problem when we were trying to ensure that club films were displayed in the correct aspect and did a few tests on the equipment available. The Widescreen Switching Signal is embedded around line 43 of the 576 line system outside of the normal viewing area so you would not expect it to get lost. However my simple tests from videos prepared from a Premiere 16:9 project showed the following in summary:

Five camcorders were tried, a Canon XL2 with native 16:9 and four Sony 4:3 cameras with 'letterbox' 16:9 feature. All these cameras correctly recorded and replayed the widescreen flag.

Five different widescreen TV sets were tried using the outputs from these cameras. Three of these had an Auto feature and each one properly detected and switched the display to the correct aspect ratio. The other two sets did not have this Auto feature and the aspect had to be set manually.

Four different projectors were tried. Only one had the Auto feature and this properly switched to the correct aspect. The other three had to be manually set

Two different DV Decks were tried, using the tapes produced from the five cameras. The JVC HR-DVS3 played correctly with the TV display switching automatically. The Panasonic NV-DV2000 played OK but did not pass the switching signal and the display had to be set manually.

So the chances are that your tapes will play correctly unless the projectionists DV Deck or Projector do not meet the required standard, and this is out of your control.

Why not record a few 16:9 tapes and play them through a TV set or projector set to Auto mode that you know works properly and see if correct switching takes place.

Chris
Peter Copestake
Posts: 340
Joined: Sun Feb 11, 2007 2:23 am
Location: Colne, Lancashire

Re: How do I know it is 16-9?

Post by Peter Copestake »

This is very naughty of me but I couldn't resist -

My WHS diary quote for 14 July says :-
'A wide screen just makes a bad film twice as bad.' (Sam Goldwyn)

So, like Dave apparently, I think I'll stick to 4:3, hoping my films will be half as bad.
Peter Copestake
tom hardwick
Posts: 914
Joined: Mon Jan 29, 2007 9:59 am

Re: How do I know it is 16-9?

Post by tom hardwick »

When I shot 4:3 movies in the TRV900 and VX2k years ago my viewfinders masked out a whole lot of the recorded image because of the horrible overscan built into all CRT TVs. Because of this I've got far more headroom than I imagined.

Nowadays the entire frame is shown on most flat-screen (plasma and LCD) TVs, so simply masking down the original 4:3 image to 16:9 works pretty well I find. In other words I can show my old 4:3 films zoomed up to screen-fill a modern widescreen TV and it's very rarely do I think I've got the framing wrong.

tom.
User avatar
billyfromConsett
Posts: 489
Joined: Sun Mar 04, 2007 3:27 pm
Location: Consett

Re: How do I know it is 16-9?

Post by billyfromConsett »

I've not ever noticed that when I put a 16:9 movie onto a standard def camcorder, that the movie loses any of the info. I seem always to correctly project it from miniDV tape, often by just setting the projector beforehand.

If it means that you need to get a note to the projectionists on what projector setting to use, well without an automatic sensor, that will hopefully get it right.
tom hardwick
Posts: 914
Joined: Mon Jan 29, 2007 9:59 am

Re: How do I know it is 16-9?

Post by tom hardwick »

Billy - when you say 'standard def camcorder' do you mean one that has 4:3 chips? Of course the chip dimensions only matter when you're using the camera to film - if you're replaying a tape then the camera will display that tape in whatever aspect ratio it was shot, be it 16:9 or 4:3.

If you ask an SD camera to replay an HDV tape then of course it won't, but an HDV camera will always be able to replay an SD tape.

tom.
User avatar
billyfromConsett
Posts: 489
Joined: Sun Mar 04, 2007 3:27 pm
Location: Consett

Re: How do I know it is 16-9?

Post by billyfromConsett »

The vast majority of standard def camcorders record natively 4:3. Even my VX2100 recorded as such, although there may have been a few cams that had 16:9 chips.
My point was that SD cameras didn't seem to adjust the image information of SD 16:9 movies (not sure about the identifying aspect ratio info) but I assume also that it would leave that alone.

Part of the projection goofs I'm sure come as a result of entrants who marked their movies widescreen when they meant letterboxed, and would need projecting either 4:3 or with one of projector zoom settings to fill the screen.

Then there are the people who letterbox their movies and put subtitles in the black area at the bottom - I think 'Clint' was received as such.

I'm sure it will sort out, we're getting used to asking these questions after one or two 'adventures' at festivals.
Post Reply