View Full Version : GS400 16:9 uprez


Andre De Clercq
August 16th, 2005, 01:02 PM
How good is the 16 :9 in camera uprez with GS400. Comparable to DVX100A when set in progressive?(see A Wilt test) Is progressive in GS400 in "thin" mode by default?

Joshua Provost
August 16th, 2005, 02:39 PM
Andre,

Not sure what you mean by in-camera uprez 16:9... the GS400 uses a 16:9 footprint on the CCD in Wide mode, with a wider angle of view than in 4:3 mode. It's actually downrezing from 1152x646 to 720x480 in Wide mode, as illusrated on this page (http://panasonic.jp/dvc/gs400k/colorful.html).

GS400 doesn't do progressive, and DVX100A doesn't do real 16:9, so it's tough to compare.
Josh

Boyd Ostroff
August 16th, 2005, 03:01 PM
Andre: The GS-400 has 1/4.7" hi res CCD's which would appear to be the same as the Sony PDX-10 (or at least the specs match). So it's actually doing real 16:9 and is in fact "downrezzing" the image to 720x480 (or 720x576 PAL).

Andre De Clercq
August 16th, 2005, 03:42 PM
Thanks Joshua and Boyd. I tought it was a letterbox uprezzer. The question on progressive scan relates to what I read in the Users Manual PAL(bottom of pg 26): "Wide/pro-cinema... In addition to the effects on Wide Function,
images are recorded at a rate of 25 frames a
second with a strobe-like effect." Maybe just for PAL version?

Young Lee
August 16th, 2005, 11:38 PM
Hope this helps.

MX5000 Frame Grabs (**In 16:9 mode: MX5000 < GS250/400)

http://www.dvuser.co.kr/zboard/data/gallery/glow2.jpg

http://www.dvuser.co.kr/zboard/data/gallery/glow3.jpg

Benjamin Durin
August 17th, 2005, 02:44 AM
Thanks Joshua and Boyd. I tought it was a letterbox uprezzer. The question on progressive scan relates to what I read in the Users Manual PAL(bottom of pg 26): "Wide/pro-cinema... In addition to the effects on Wide Function,
images are recorded at a rate of 25 frames a
second with a strobe-like effect." Maybe just for PAL version?

André, the Pro-Cinema mode is not a progressive mode but a frame mode. So the GS400 internally deinterlace.
Some people like this mode, others don't.

Andre De Clercq
August 17th, 2005, 03:38 AM
Thanks Benjamin, but why do you think that frame mode is a deinteraced version and not a native progressive picture ? See http://www.adamwilt.com/DV-FAQ-etc.html#filmlook about frame mode.

Andre De Clercq
August 17th, 2005, 05:57 AM
Maybe somewhat more background info why I started this thread. I have a Sony VX2K. A good camera especially in low light conditions, but it has a poor 16:9 uprez image (vertical resolution and artifacts)..I want 16:9 on my widescreen LCD displays (37"Sharp and 40"Barco).. instead of side panneled 4:3 pictures. In addition to that I luke a smaller DV camcorder for traveling.

Boyd Ostroff
August 17th, 2005, 07:14 AM
Andre, have you ever looked at the PDX-10? If you like the VX-2000 then it would see very familiar. It also has the advantage of DVCAM recording, hi res BW viewfinder, XLR inputs and a short shotgun mike. The XLR box and mike are removable for those times when you want something small, and the camera also has builtin stereo mikes. It will give you very nice 16:9 but no frame mode.

It has perhaps been discontinued however, see the discussion in the PDX-10 forum. I suspect you can still find them though, probably at a good price too.

Of course the new Sony HDR-HC1 and HVR-A1 would also give you nice widescreen in a very small package, plus HDV. Maybe more than you want to spend though.

Andre De Clercq
August 17th, 2005, 08:01 AM
Yes Boyd PDX10 looks fine too. I will look at it in more detail (and see if still available in Europe). About the Sony HC1 I still have questions on how it handles low-light sitiuations (window and level mapping trade-offs)) and fast moving objects (rolling shutter). Also my NLE is not MPEG2 compatible,,,

Boyd Ostroff
August 17th, 2005, 08:20 AM
If you aren't ready for HDV then the HC1 allows you to shoot in regular DV mode (AFAIK), but you still have the advantage of the hi-res 16:9 native CCD's. When used this way you avoid the MPEG issues with movement.

Andre De Clercq
August 17th, 2005, 08:40 AM
Boyd, I mean the CMOS related motion problems with fast motion caused by the rolling shutter.

David Andrews
August 17th, 2005, 12:03 PM
I have a PAL version of the GS400 and now always use the 16:9 widescreen mode. This delivers good results for me. I understand this mode uses 50 frames per second interlaced in PAL format.

I have not used the 16:9 "pro-cinema" frame mode. This uses 25 frames per second full frame mode.

Andre De Clercq
August 17th, 2005, 02:01 PM
Thanks for correcting me David. Indeed , the "wide" mode produces standard interlace anamorphic pics (you mean 50 interlaced fields/sec.I suppose). I am not a specific progressive scan enthousiast, but depending on the camera's vertical filtering (thin/thick)and the performance of the deinterlacer/rescaler in flatscreen LCD displays, vertical resolution can be higher for native progressive images.

David Andrews
August 18th, 2005, 12:14 AM
This subject came up on one of the DVdoctor forums recently, to be found here:
http://dvdf.hexus.net/showthread.php?t=34365&highlight=GS400+16%3A9

It may be of interest. The expert here is Alan Roberts.

Benjamin Durin
August 18th, 2005, 01:48 AM
Thanks Benjamin, but why do you think that frame mode is a deinteraced version and not a native progressive picture ? See http://www.adamwilt.com/DV-FAQ-etc.html#filmlook about frame mode.

From the article you quote, frame mode is made from interlaced scanning and is not native progressive:
"Several cameras, including the Panasonic AJ-EZ1 and AJ-D200/210/215 and the Canon XL1 and GL1, have a "frame movie mode" or "frame mode" switch that changes the way the CCD is read out into buffer memory from interlaced to progressive scanning."

From http://www.camcorderinfo.com/:
"Pressing the widescreen / pro-cinema mode button a second time will turn on the Pro Cinema Mode. There was much excitement over the Pro Cinema function when the camcorder was first introduced because Panasonic made it appear as though it was a 30 frames progressive scan mode. While the casual user will notice that the Pro Cinema mode looks like film, it is not true 30P and appears to be the same frame mode as on the PV-DV953. The mode also changes the color cast and contrast of the image slightly, to give it more of a film look. It's a neat feature, but it doesn't replicate true progressive scan recording."

So the GS400 is not progressive but the 16/9 picture is beautiful !

Joshua Provost
August 18th, 2005, 10:23 AM
Wow, I'm glad I don't read that forum. What a bunch of incorrect information! How did they get to the point where you are *adding* the pixel count from all 3CCD to get the resolution of the camera?! 3x 1.1MP CCDs = close to 4MP?! Those are the separate RGB components of the same 1.1MPs. The 4MP number comes from interpolation. My goodness...

Leigh Wanstead
August 18th, 2005, 01:38 PM
Wow, I'm glad I don't read that forum. What a bunch of incorrect information! How did they get to the point where you are *adding* the pixel count from all 3CCD to get the resolution of the camera?! 3x 1.1MP CCDs = close to 4MP?! Those are the separate RGB components of the same 1.1MPs. The 4MP number comes from interpolation. My goodness...

I am confused about that. Can anyone clarify "3x 1.1MP CCDs = close to 4MP" statement?

Joshua Provost
August 18th, 2005, 02:13 PM
I am confused about that. Can anyone clarify "3x 1.1MP CCDs = close to 4MP" statement?

Leigh,

It was this link http://dvdf.hexus.net/showthread.php?t=34365&highlight=GS400+16%3A9. The statement doesn't make any sense, but it's what the moderator at that link was saying. Yikes.

Josh

Leigh Wanstead
August 18th, 2005, 02:41 PM
Leigh,

It was this link http://dvdf.hexus.net/showthread.php?t=34365&highlight=GS400+16%3A9. The statement doesn't make any sense, but it's what the moderator at that link was saying. Yikes.

Josh

Hi Josh,

I read that link already and at time I read the link I thought that no one object "3x 1.1MP CCDs = close to 4MP" in that thread, so it might be correct. But now you said that is wrong. I . That is the confusing I am facing now.

Regards
Leigh

Guy Bruner
August 18th, 2005, 07:17 PM
There is a lot of bad information in that thread. It is clear that, although Roberts may know about DV, he doesn't have a clue about the technology in the GS400.

Chris Hurd
August 18th, 2005, 11:41 PM
Among a number of things wrong with that thread is the statement about 3-CCD camcorders in general: "because the green sensor will be offset spatially from the red and blue by half a pixel horizontally." He is describing the Pixel Shift process, invented by Panasonic and adopted by most all camera makers. Trouble is, not all 3-CCD sensor blocks use Pixel Shift. Some do, and some do not. And there are different varieties of Pixel Shift: you can have a physical offset in either axis, or an electronic offset in either axis, or a physical offset in one axis and an electronic offset in the other. Main point being though that not all 3-CCD camcorders use Pixel Shift.

But enough of discussing the threads from other sites, fellows... this is DV Info Net... let's discuss our own topics, shall we? Thanks in advance,

David Andrews
August 19th, 2005, 02:49 AM
But enough of discussing the threads from other sites, fellows... this is DV Info Net... let's discuss our own topics, shall we? Thanks in advance,

Sorry to offend by cross referring.

Re GS400 image sensors and pixel counts, my GS400 operating instructions state:
Image sensor 1/4.7 inch 3CCD image sensor (Effective pixels: moving picture/690k x 3, still picture/990k x 3, Total:1070 x 3).
Still image size: megapixel recording 2288 x 1728 (4.0 million pixels).

For the reason I described Alan Roberts as an expert please see BBC R&D White Paper WHP034 here:
http://www.bbc.co.uk/rd/pubs/whp/whp034.shtml

Chris Hurd
August 19th, 2005, 08:06 AM
Pixel Shift does in fact allow you to get a higher-res still image out of a 3-CCD camcorder. For the GS400 to have this is not a new thing to the industry. The Canon GL2 for example will provide a 1.7mp still image to memory card, and it has three CCD's at 410kp/380kp (total/effective kilopixels) each. Pixel Shift creates more sampling points per each pixel photosite.