Squeeze mode versus 16:9 Mode

P

Policar

Carbonite Member
The only camera I currently own is a four year old digital 8, but I'm seriously considering a dvx100a. The one thing that seriously bugs me are the 4:3 CCDs, since I'll be shooting almost exclusively in 16:9.

Anyhow, I was just wondering if squeeze mode offered any advantages over 16:9 mode. Ideally, I'd shoot in 4:3, then crop the image to my liking, and letterbox it within my NLE, but somehow this doesn't seem like the best option for preservation of resolution. I know shooting in squeeze mode fills more pixels, but does it actually create a better looking image?

Does working with 16X9 footage in squeeze mode to create an anamorphic dvd have any advantages over scaling 720X360 video up to 720X480, other than time savings?

I'd be shooting in 24p, btw, and probably editing in Final Cut Pro.
 
Re: Squeeze mode versus 16:9 Mode

This has been discussed in this forum quite recently.  Try using the search feature.  I'm sure you'll find all your answers.
 
Re: Squeeze mode versus 16:9 Mode

I'm curious what settings you all use for your scenefile when shooting in squeeze mode? Any preferences?
 
Re: Squeeze mode versus 16:9 Mode

I don't own an "A", but regardless, I shoot everything in 4:3 and mask the LCD with tape for widescreen, and don't shoot with the Letterboxed mode

An advantage to that is it gives you more room in post to play if you need it, and you wouldn't have that shooting squeezed, either.
 
Re: Squeeze mode versus 16:9 Mode

I was thinking the same thing about cropping in post, but then I read that the DVX uses some magical DV codec that compresses the black letterboxing differently, allowing more data to be used for the footage itself.

I always thought dv was dv, but no one seemed to refute this....
 
Re: Squeeze mode versus 16:9 Mode

It's not magical, it just a methodology to how DV25 can use static macroblocks for extra dataspace prior to DCT compression, then return that macroblocks dataspace back to its proper grid assignment at decompression.

The reason no one disputes or for that matter guarantees that this occurs is because we don't know for sure if this is or is not happening.  All we can know is that it is allowable and to some extent used.  To what depth it may or may not be used is something only each codac manufacture can say... And they don't say.

If you're really interested, here's a link to start you off, but be prepared to read and think analytically for a good amount of time.  It is interesting to understand how various compression schemes work, but it is also somewhat frustrating as there is an exactness to this which is alluded to, but not fully shown.  

Hence, the black art in writing better codacs.

Link: http://www.adamwilt.com/DVvsMJPEG.html

-Rodger
 
Re: Squeeze mode versus 16:9 Mode

Interesting thread,

I almost always get carried away by wanting to know the technical stuff. I still believe it's important, but I guess some of like to go too far.

I've done lots of subjective/qualitative image testing on my DVX100A, and to me there is very little difference between the squeeze mode and the letterbox mode. A difference IS noticiable, but not enough so that I can instantly pick out the faults. I can only detect the difference when I compare the two images in blown up view, and only when they are placed next to each other.

This is why I asked, about a month ago whether anyone has visual pics of the Panasonic's Anamorphic adapter, of which no one replied. I wanted to test the usability of that adapter as notably raised by marjamar in one of this previous posts.

To me, the adapter brings with it, hundreds of other hurdles that it's not worth using: inability to use screw in filters, added barrel distortion, etc, etc.
 
Re: Squeeze mode versus 16:9 Mode

Just read on 2 pop I think maybe DVX user.. About this same subject. The test conducted said there was no discernable difference between letterbox and squeeze mode.. when blown up 400X in photoshop... Anyone else have a difference in opinion?
 
Re: Squeeze mode versus 16:9 Mode

There should be a very minimal difference between stretched letterbox and squeeze mode.  Squeeze mode has the potential for being better, because the stretch happens before compression.  In letterbox, the whole frame gets compressed, then uncompressed and stretched in post, then recompressed.  So squeeze mode could (and *should*) give slightly better results. (likely the only way it wouldn't is if Panasonic's stretching algorithm was lame.  According to Adam Wilt's test charts, that's not the case, and squeeze mode does a good job in progressive (but apparently a rather lame job in interlaced).

So, saying that squeeze and letterbox/stretched are extremely close in quality, the anamorphic should handily trump squeeze mode.  I conducted extensive tests between anamorphic and stretched letterbox, and the anamorphic was much better.  To my subjective opinion, it renders about 20% more detail than stretched letterbox does.

Some day I'll take my anamorphic adapter over to a friend's house (who just got a 100A) and we'll conduct some tests... but I already know what the answer is going to be.
 
Re: Squeeze mode versus 16:9 Mode

Is it possible if you can post those frames?

It's not that I don't believe you, I'd like to see it for myself :)
 
Re: Squeeze mode versus 16:9 Mode

It's been close to a year since I did this, so have patience... I don't even know where that stuff is.

Hold on...

Okay, here's a bunch of frames I dug up.

This first one is some pine needles on a branch.
http://www.icexpo.com/Anamorphic-Branch.jpg
http://www.icexpo.com/Letterbox-Branch.jpg

The difference is really easy to see if you put 'em on a timeline and step back and forth between 'em, especially if you're looking at the wood of the branch.

Then I went through and compared anamorphic vs. letterbox shooting the same frame of a newspaper.  Nothing scientific, I just slapped a newspaper on a black background and then compared for various zoom settings.  The zoom settings are not the same for both, of course, because the adapter gives you a wider field of view.  But these are paired together based on basically the same field of view:
http://www.icexpo.com/AnNewspaperZ13.jpg
http://www.icexpo.com/LbNewspaperZ00.jpg

http://www.icexpo.com/AnNewspaperZ65.jpg
http://www.icexpo.com/LbNewspaperZ54.jpg

http://www.icexpo.com/AnNewspaperZ33.jpg
http://www.icexpo.com/LbNewspaperZ17.jpg

http://www.icexpo.com/AnNewspaperZ99.jpg
http://www.icexpo.com/LbNewspaperZ92.jpg

Viewing 'em on a computer, from JPG's of the stills, doesn't show much difference, although the Z65/Z54 pair shows some words that are just easier to read on the anamorphic.  However, viewing the raw DV files projected on a 10' screen, the anamorphic was clearly superior in all the test shots except the full-telephoto -- on full telephoto the astigmatism was too much to overcome, and the results were on par with stretched letterbox.

I came away from this test with the conclusion that if you're going for the small screen, the anamorphic isn't worth the hassle.  The larger the screen you use, the more you notice the difference.  On a 10' screen the difference was quite noticeable, and definitely clearly in the anamorphic's favor (as long as you stay away from full telephoto).

It wasn't even close, really -- it was "wow, that's better".  I imagine on a 20' or 30' screen it will only be moreso.  But on a small screen, examining these pictures at 100% size on PhotoShop, it's tough to see much of a difference.
 
Re: Squeeze mode versus 16:9 Mode

Clearly squeeze mode is better then with the anamorphic adapter, but I'm still not convinced that it's better when shooting without it.

That one shot of the pine needles is pretty convincing. If I had the money, I'd definitely buy an anamorphic adapter thingy.
 
Re: Squeeze mode versus 16:9 Mode

Wow,

I've only seen one test before but what you've shown me is making me think twice -- especially the pine tree image. If you have more, I'd love to see them.

I'd also like to ask a few questions.

1) The anamorphic image is squeezed, can you tell me how you got the two images to be the same size? Biliniear or Bicubic interpolation in Photoshop?

2) I'm also assuming you set-up the camera to a low F-stop?

3) I knew that the anamorphic creates an even larger wide angle, but is there a Focal distance relationship chart that can be looked up?


And finally, what about Century Optics' new $2000 lens. NAB is right around the corner, so should I be weary of that? Anyone going to NAB??? :)


P.S. Again, I can't thank you enough, I was planning to rent the damn Lens for some testing, but you may have saved me some money.
 
Re: Squeeze mode versus 16:9 Mode

Resizing was done in Vegas.

The f-stop was not too open, I think I was lighting for a 5.6 or an 8 on the newspaper shots (I wanted the determining factor to be resolution, not bad focus). The pine needles shot was done with a SoftScreen behind it, so the optical DOF effect isn't done by the iris.

As far as the wide-angle effect of the anamorphic, it's 33% wider than without.

Again, I'd like to run some more tests some day with the DVX100A against true "squeeze mode" (this was stretched letterbox). I don't know when or if I'll get to it, but I think that's the relevant comparison now.
 
Re: Squeeze mode versus 16:9 Mode

Damn, you guys are quick to reply -- luck for me.

Have you tried comparing the images using the Focus chart that people use (Adam Wilt particularly, on his test for the DVX100A).

Also, have you heard anything about the Century Optics? I've seen that one post about it having it's own focus, and it having a crazy iris size.

I guess the Sony and JVC's HDV sweeps, it might have blown the hype off of that thing.
 
Re: Squeeze mode versus 16:9 Mode

Century's anamorphic adapter still does not exist. Perhaps something will be shown at NAB, but as of today there is no product available.
 
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