16:9 vs. 4:3 Resolution/Cropping
 

Happy New Year!
There seem to be lots of recurring questions about 4:3 resolution vs. 16:9 resolution and image cropping in 16:9 mode. So, I decided to post some frame captures that show both. I just set up a quicky resolution chart and shot a few frames of video in 4:3 frame mode and 16:9 frame mode. Then, I brought the video into Vegas 4.0 and captured a frame from each. I did not move the camera between shots so the images reflect the in-camera vertical cropping that the DV953 does to achieve 16:9. They are in JPEG format.

DV953 Sample Shots

If you want more info on 16:9 in 4:3 miniDV cameras, go here and here .

Thanks, Guy!

so it really dosent make any sense to shoot in 16:9 when you can just crop it in post?

I wouldn't go that far. For best results in-camera 16:9 would be the way, I think; especially with framing during shooting.

Well, I didn't like those two frame grabs, so I added a couple more. Looks like 4:3 and 16:9 have the same resolution to me. Maybe some discerning eye can tell the difference?

From the results of the EIA test pattern, I would say it is better to shoot in 16:9 than to crop in post. The reason is that you retain full resolution. If you crop in post and expand to fill, you lose resolution. In Vegas, I just capture the clip shot in 16:9 as regular DV (720x480), then set the clip properties to DV Widescreen. Vegas automatically establishes the right aspect ratio. This seems much easier to me than having to put a black bar mask on the top and bottom or use pan and crop.

To achieve 16:9 the DV953 has a 1.3x vertical zoom which is the same as the Japanese MX5000. Oddly, the PAL equivalent, MX500, has no vertical zooming. Even with the slight vertical zooming on the DV953 its still a great asset along with the frame mode (IMO).

The Japanese GS100 offers a wider angle of view in its widescreen mode (not cinema) but with a 1.04x vertical zoom.

Guy, why are your widescreen frame grabs 873x480?

<<<-- Guy, why are your widescreen frame grabs 873x480? -->>>

Hmmmm, Tommy, good question...I don't know. Didn't pay much attention until your question. They are 872x480, BTW...my bad. This is the way Vegas converts the 720x480 anamorphic clip from the DV953 when the clip is identified as DV Widescreen. It's not 1.78:1 with that pixel ratio. Should be 854x480?

Hi Tommy. I'm shooting wth a PAL mx500 & i didn't really understand the vertical zoom point you mentioned. What is this difference, good or bad, & why does it exist ...? thanks ...

Emmet,
In the DV953 (MX5000) 16:9 mode, the image is stretched vertically. It looks like the camera has been zoomed in, but the geometry is elongated vertically. Go here to see a comparison of several contemporaneous camcorders (it's in Japanese but you should be able to figure it out). Scroll down to the bottom to see how the viewfinder looks in 16:9 mode as compared to 4:3 mode several lines up. I'm not familiar with the MX500 or GS100, but apparently they do not vertically stretch the image like the DV953 and MX5000.

I have a letterbox calculator here that also explains a lot
behind calculations that I believe are correct.

I've researched the Vegas aspect ratio matter quite a bit and
according to my sources they are using the original numbers
as "made" by the industry. However, they don't seem to be the
numbers everybody else is using (ie, widely accepted).

Emmet, maybe this photo will help explain vertical zoom (or lack thereof) on the MX500. You'll notice that while the MX500 does not have a vertical zoom to achieve 16:9 it does not widen the angle of view as with some cams.

http://img.villagephotos.com/p/2003-...IYZP-1-1-5.jpg

This next link (in Japanese) demonstrates how the GS100 obtains its 16:9 view.

http://panasonic.jp/dvc/gs100k/ki_wide.html

ok, thanks guys. gosh, my camera looks terrible in alot of those shots on the japanese page. guess if i could read japenese i'd get even more depressed.....

No worries Emmet as that Japanese site tends to favor Sony cams.

Here is the same page but translated to English.

http://babelfish.altavista.com/babel....html&lp=ja_en

<<<-- Originally posted by Rob Lohman : I have a letterbox calculator here that also explains a lot
behind calculations that I believe are correct.

I've researched the Vegas aspect ratio matter quite a bit and
according to my sources they are using the original numbers
as "made" by the industry. However, they don't seem to be the
numbers everybody else is using (ie, widely accepted). -->>>

Rob,
So, is this a "square pixel" vs. "rectangular pixel" issue? I have seen several threads on other forums on the .9091 number...maybe some of your posts. Does this number change for widescreen? Since the DV953 (and other camcorders) stretch the pixels vertically in 16:9, does this affect Vegas's simulation of picture aspect ratio and make the .9091 number incorrect? Or, am I way off base here?

The numbers I'm talking about is pixel aspect ratio. Indeed, how
a pixel will look. If you enter the number 0.9091 from Vegas you
will see as soon as you enter the second 9 on my page that the
result is a 4 pixel difference in the size of the mask (or usable
area).

Basically my page calculates how much pixels your mask needs
to be if you want to SIMULATE 16x9 aspect ratio (ie, with black
bars). Or how much you need (to chop of the image and) stretch
the image vertically to do a post 16x9 aspect ratio.

And yes, that number definitely changes if you are actually
working in a 16x9 aspect ratio (instead of simulating one). See
the Vegas project settings to see what they use then. Keep in
mind that if you are already working in 16x9 you basically don't
need to calculate anything. If you want to go out to 4x3 then
just output to that. Vegas will add black bars automatically.