16:9 vs 4:3

[Shaggy Franks]

Hey,

Not sure if this has been posted here before but I found this on the videolikefilm.com page
Enjoy

Q1) "My MiniDV or DVCAM camera does not have a "real" 16x9 CCD in it ... I hear that the 16x9 is "fake" and I shouldn't use it at all"
FIGURES TO NOTE:

A 4x3 image cropped to 16x9 uses only 75% of the available pixels of the CCD and only 75% of the available data space on the tape.

A 16x9 "interpolated mode" image presented in 16x9 uses the EXACT SAME 75% of the pixels of the CCD as above, but has the advantage of using 100% of the available data space on the tape.


More at videolikefilm.com

[Boyd Ostroff]

I think you need to do some tests with your own camera to determine how applicable this is. I understand his logic, but think different cameras process cropped and stretched 16:9 differently.

For example, on the VX-2000/2100 and PD-150/170 the builtin 16:9 looks pretty bad. I've done some comparisons here which convince me that cropping in post is about the same. Actually, someone else did a test which showed even better results using letterboxed 16:9. They just showed the letterboxed video on their widescreen TV in "zoom mode" such that the TV itself scaled the letterbox to fill the 16:9 screen. The scaling hardware did a much better job than either the built-in 16:9 or crop/stretch in post.

So try some experiments with your own camera before you drawing any conclusions about the best technique.

[Rob Lohman]

Although the compression note is in theory correct it has not been
proven that it actually helps that much in the real world (ie, you
see the differences). Personally I like the option to vertically frame
my footage after shooting etc.

[Bob Zimmerman]

Can you in post production do a better job of making 16:9 compared to the cameras not making a true 16:9?

[Rob Lohman]

That depends on a lot factors, including the quality of the resampling
(remember, they need to stretch the frames after the crop vertically
to fit in the 480 lines in REALTIME!) done inside the camera and
the algorithm your NLE will use to do the same in post. It also
depends on how much of an advantage this extra compression
bandwidth will yield in the realworld.

But basically I "feel" (no facts) that we can do it just as good in
post, perhaps better. My main advantage is that I can reframe
the picture vertically which I really like.

You can always do some test shoots to see what you look yourself
and what works good for your workflow Bob!

[Robin Davies-Rollinson]

Rob,

I've tried cropping and stretching to produce full height anamorphic images in Avid and it's really crap compared to what the XM2 can do in the camera...
..not to mention the time taken to render.

Robin

[Rob Lohman]

Sorry to hear that Robin, I guess Avid is not so good with this
then. Perhaps in your case it is better to stick with the XM2
function. As I said, it all depends on the quality of the algorithms
on both ends.

[Michael Sinclair]

Anyone know what the specs are on the Canon Optura 300 in terms of the 16:9 mode? I have one but I am pretty new at this. Does it crop or have true 16:9?

[Tom Voigt]

Can we assume that this sensor is using about 900 rows which gets sampled to 480 when in 16:9 mode?

If this is true then there might not be any penalty on cameras with multi-megapixel still modes.

-Tom-

[Rob Lohman]

If it does that then you have true 16:9, but it is very doubtful it
would do that. If you have the camera in 4:3 and then switch it
to 16:9, does your field of view get wider? (ie, you see more
than in 4:3 mode, instead of less)

[Sean McHenry]

We went through a huge amount of this thread in the PDX10 forum. For my money, you can't beat a true 16:9 (anamorphic) as it uses all the pixels it's supposed to to make the image. That is, you are right in that 4:3 in letterbox mode, like on the AG-DVX100 for example, simply masks the upper and lower sections with black. The image is 4:3 but you are throwing away all that resolution on black space. On top of that, you are only fooling those with 4:3 sets into thinking they are watching 16:9.

Best bet if you are serious about getting the best 16:9 is to look into a Century Optics anamorphic adapter. They aren't cheap but they allow you to use all those pixels you paid for.

From a semantics point of view, the image is, or isn't, 16:9 and 4:3 at the same time. I figure it this way, if folks using the AG-DVX100 and it's letterboxing kin can make actual documentaries and have them look not too bad using less pixels in letterboxed format, it can't be all bad. Right?

Still, give me my PDX10 and anamorphic any day.

Stop by the PDX10 forum for more on all this and the cameras abilities and disabilities.

You'll find lots from Boyd and myself over there.

Sean McHenry