Aspect Ratio Differences

[Rafael Amador]

[Alexander Lee] “Rafael, I think the kid’s head is actually that long :-p “
My appreciation have no much scientific base, but I live border with china and I have 5 oriental-kids.
Really that face it looks to adult like for me.
Anyway some times even for the one that shoots the picture it can be difficult to detect a certain distort in a picture. The face may not gives you enaugh idea and you may need some othe visual refference.
As I said no one of the two pictures looks fully OK for me.
Cheers,
rafael

http://www.nagavideo.com

[Alexander Lee]

You could be right. I’m not sure as it’s been years since I’ve seen the kid.

[Alexander Lee]

Here’s the settings:

Hm, they don’t differ.

[Andy Mees]

I don’t see that very clear. Normally QT display Square pixels so make faces more elongated, Greco like.

Yeah, you had me going for a while there Rafa, but then I remembered that we are PAL boys and Alexander is in NTSC land. Pixel Aspect Ratio of course is deternibed by the format, and D1/DV – NTSC, as per the original format here, has a native PAR of 0.9 … its supposed to be slightly taller than it is wide. (In PAL land its 1.07 so just slightly fatter than it is tall). D1/DV NTSC, when displayed with square pixels as in the first (upper) image, will appear somewhat fat.

But in the FC picture (lower) there is a big cropping on top of the head of the boy.

You know what, as the letterbox is encoded in the image then I’d say most likely that we’re looking at screen shots of different frames, not far off but different nonetheless, hence the slight change in the framing.

[Alexander Lee]

I’m revisiting this post as I still have the same issue. When I try to export a still in FCP using Quicktime conversion, it looks fat. Is it a simple matter of video pixels being a different size than square computer pixels? But since I’m viewing both images on a Mac, it shouldn’t really matter…

Also, in regards to the kid, his head is that long. He has an “unusually” long head. I compared it to still photos I have of him.

[Rafael Amador]

[Alexander Lee] “When I try to export a still in FCP using Quicktime conversion, it looks fat. Is it a simple matter of video pixels being a different size than square computer pixels? “
Yes. If you open the picture in Photoshop and you “correct for aspect ratio” should look OK.

The same picture can look different depending of how QT display it.
My first post was miss leading because the effect of the “Square pixels” display is the opposite in NTSC than in PAL.
When you display NTSC stuff as Square pixels, people gets fat, while with PAL, people gets thinner.
This was cleverly pointed by Andy.
rafael

http://www.nagavideo.com