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-   Sony VX2100 / PD170 / PDX10 Companion (https://www.dvinfo.net/forum/sony-vx2100-pd170-pdx10-companion/)
-   -   16:9 Real World Result with PD's and VX's (https://www.dvinfo.net/forum/sony-vx2100-pd170-pdx10-companion/88405-16-9-real-world-result-pds-vxs.html)

Chris Barcellos April 25th, 2006 04:49 PM

Quote:

Originally Posted by Robert Martens
As for losing resolution, well, as far as I know the only way around that is a 16:9 anamorphic adapter, like the one from Century Optics. Barring that, the only way to get a 16:9 image is to get rid of some scanlines, so "throwing away" resolution isn't so bad: you couldn't use it otherwise. You lose image dimensions when you apply some sort of mask, sure, but not detail in the remaining image area.

Right. And that works expecially nice when you are only letterboxing for a 4:3 output. Well at least this discussion is making it clearer to me, what is going on...

Marco Wagner April 25th, 2006 08:12 PM

Nice Find
 
Hey all I found this link that gets into nice detail about all the aspect ratios from film to HDTV. Here's the link


http://members.shaw.ca/quadibloc/other/aspint.htm

This one actually has a flash that shows some differences.

http://www.widescreen.org

Laurence Kingston April 25th, 2006 09:16 PM

What I recommend is to try a little of each way to test and compare. When I did this, the camera 16:9 mode looks the same as the post crop and stretch which looks the same as matting the top and bottom and cropping and stretching. No matter how you do it you end up with the same thing: 360 lines of resolution stretched out to 480 lines. As far as I have been able to see, it looks the same no matter how you do it, so you may as well do it with the camera and save the extra steps.

My main camera now is an A1, but I still find myself using the VX2000 for low light shots. When I do this, I just shoot in the 16:9 mode. That way I can put the shots on the same timeline. In bright light the A1 blows the VX2000 away, but in low light, the VX2000 is better, interpolated lines and all.

Bob Hart April 26th, 2006 02:13 AM

My personal preference would be to make a mask of transparent coloured lighting gel material with a 16:9 frame cut in it, attach this over the LCD screen and use this to shoot for 16:9 safe image area in 4:3 mode. I assume you are able to use the cam in its underwater housing with the screen opened. If you are using a separate viewfinding device, forget anything I have said.

Which coloured lighting gel works best for underwater light, I cannot tell you, only an experiment can.

An underwater camera is a difficult enough beast to control, so having that little bit of vertical leeway by shooting in 4:3 to recover correct framing in post is worth keeping.

Lou Bruno April 27th, 2006 06:13 AM

This post is 100% correct. There is such a loss of Vertical resolution that the picture is about VHS quality. Now, put that on a large widescreen!


Quote:

Originally Posted by Chris Barcellos
Robert:

I don't think anyone has a problem with the 2 cents everyone is putting in. My problem with this whole thing is I don't get the technical side of it.

From what I can make out, DV 16:9 in the Sony still comes packaged inside a 720 wide frame. And so does 4:3. So it seems to me you should avoid the 16:9 hocus pocus in the camera, and stretch into your 16:9 frame in post where you have more control over the output. Thats why if I know I am going out to 16:9 I would rather choose a matte in camera, over the 16:9 selection. Others just put a tape or guide over LCD to approximate letter box and do it on time line in post. But no matter what you choose, if you go to 16:9 you loose use of some of the pixels, and that is an effective loss of resolution.


Tom Hardwick April 27th, 2006 07:50 AM

You're probaly speaking tongue-in-cheek, Lou, but the VX2k in its 16:9 mode is simply miles better than anything I've seen off S-VHS, let alone VHS.

tom.

Nick Hope April 28th, 2006 03:46 AM

Thanks for the useful discussion everyone.

I'm set up for the memory mix method now but I'm still recommending to the customer that I shoot 4:3 with the external monitor masked top and bottom with black insulating tape (in lieu of suitable gel).

For film transfer would you shoot interlaced or progressive? Bear in mind my camera is PAL.

Nick

Tom Hardwick April 28th, 2006 04:52 AM

Don't shoot progressive on the Sony. It defaults to 12.5 full resolution fps. Fine if you want to use the camera as a motor-drive still camera, but far too jerky motion for movies.

Aviv Hallale April 29th, 2006 01:46 AM

In general, is the widescreen mode of the VX2100 unusable for anything professional, or can it still be passed off as something good to people that don't really know the difference between it and a camera with native 16:9?

How does it compare to the Canon XL1 and other cameras in its class in terms of widescreen?

Tom Hardwick April 29th, 2006 04:19 AM

The VX2100 does what they term an 'anamorphic' widescreen, although the viewfinders are shown letterbox so there's no horizontal compression distortions. Much nicer than the XM2, say.

I shoot with my VX2000 in the 16:9 mode professionally when the demand is there. Last week for instance I shot a stage show and the 16:9 is a perfect aspect ratio to use. If I'd have shot in 4:3 the bottom of the screen would have been heads of audience and the top of the screen would've been curtains, so effectively my resolution of the actors was unchanged.

tom.

Marco Wagner May 3rd, 2006 10:14 AM

What about going in reverse? Shooting with the in-camera 16:9 and later shrinking it down for 4:3....Anyone?

Philip Williams May 3rd, 2006 01:11 PM

Quote:

Originally Posted by Aviv Hallale
In general, is the widescreen mode of the VX2100 unusable for anything professional, or can it still be passed off as something good to people that don't really know the difference between it and a camera with native 16:9?

How does it compare to the Canon XL1 and other cameras in its class in terms of widescreen?

Just my opinion, but I think the 16:9 digital sampling on the VX/PD series is terrible. My old Canon Elura had a FAR higher resolution 16:9 image - and it used the same basic crop and scale technique. If I were shooting 16:9 on a VX/PD I'd go 4:3 and crop in post. I've got some screenshots of rez charts from my Elura buried on my web site, and its 16:9 was actually pretty decent.

www.philipwilliams.com

Tom Hardwick May 4th, 2006 03:17 AM

I agree Philip, and if you're talking NTSC I'd agree even more with your thought that the VX/PD is not for 16:9.

My PAL 576 lines are reduced to 432 in 16:9 which is just about accep[table on a decent 16:9 TV, but NTSC's 360 lines in the same mode just isn't good enough.

When I replay my stage show footage on a conventional; 4:3 TV it appears masked, but the resolution of the performers is the same as if I'd filled the screen with audience heads and curtains.

Marco - What are you thinking? Go stand in the corner.

tom.

Chris Barcellos May 4th, 2006 09:47 AM

Quote:

Originally Posted by Tom Hardwick
I agree Philip, and if you're talking NTSC I'd agree even more with your thought that the VX/PD is not for 16:9.

My PAL 576 lines are reduced to 432 in 16:9 which is just about accep[table on a decent 16:9 TV, but NTSC's 360 lines in the same mode just isn't good enough.

When I replay my stage show footage on a conventional; 4:3 TV it appears masked, but the resolution of the performers is the same as if I'd filled the screen with audience heads and curtains.

Marco - What are you thinking? Go stand in the corner.

tom.


I've been trying to "get" this for a long time. Why is there a need for digital resampling in the VX/PD in the first place. If the DV wide screen and DV Standard are both 720 wide, why is resampling need to turn it to 16:9. It would seem that in wide you just cut the top and bottom off and have less lines, that the picture showing would have the same resolution as a comparable area of 4:3. I am sure I've missed something obvious in my self taught DV 101 class, but its not making sense to me. Anyone ?

Robert Martens May 4th, 2006 11:01 AM

Quote:

Originally Posted by Chris Barcellos
It would seem that in wide you just cut the top and bottom off and have less lines, that the picture showing would have the same resolution as a comparable area of 4:3.

It would seem that way based on what one sees in this camera's LCD and viewfinder, and indeed many cameras DO achieve a widescreen image this way. This is also what you are doing when using the Memory Mix function; the image area remaining inside the letterbox has the same detail level as it would in a 4:3 image. But that's NOT how the built-in widescreen function works on the VX2000.

This camera DOES crop the image to make it 16:9, but something else happens before anything is written to tape. The "stretch" I was talking about earlier is that something. The image is cropped, but then digitally resampled vertically to make it a 4:3 image. Due to the vertical resizing, the picture is naturally distorted, but your editing software corrects for that distortion when you import the footage.

Is it strictly necessary? Well, no, I suppose not, which is why so many recommend either the Memory Mix trick you use, or simply shooting a full 4:3 that is framed for 16:9 and cropping after the fact. The aforementioned digital resampling would be bad enough on a progressive image (I think), but performing the same scaling on interlaced footage is even worse. A few posts ago I was saying that it wasn't so bad, apparently I'd forgotten the truth; I went back and looked at some test footage I'd shot using the in camera widescreen mode, and while the nearly-horizontal lines I recorded aren't too offensive, nor is the overall level of detail (only 360 NTSC lines, but it's not too muddy to me), but the ugly, thick black ring around some moving objects is.


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