shutter on or off - Page 3 at DVinfo.net

Go Back   DV Info Net > Sony XAVC / XDCAM / NXCAM / AVCHD / HDV / DV Camera Systems > Sony XDCAM EX Pro Handhelds

Sony XDCAM EX Pro Handhelds
Sony PMW-300, PXW-X200, PXW-X180 (back to EX3 & EX1) recording to SxS flash memory.


Reply
 
Thread Tools Search this Thread
Old November 14th, 2008, 02:38 AM   #31
Major Player
 
Join Date: May 2008
Location: Nuremberg, Germany
Posts: 285
Quote:
Originally Posted by Serena Steuart View Post
If I were putting together an opinion on this I'd suggest that the greater gain in 50i is achieved by stacking frames. If you take 2 frames (50P) to output one, then there is no point in throwing away data that can be utilised.
Each of two 50p-frames becomes one field of a 50i-frame. But one field has got half of the resolution of one 50p-frame, so you can add every two rows of the 50p-frame to one. And that's vertical box-low-pass-filtering with 6db-gain. ;)
Dominik Seibold is offline   Reply With Quote
Old November 14th, 2008, 06:01 AM   #32
Major Player
 
Join Date: Jun 2006
Location: Studio Alnitak, Melbourne, Victoria, Australia
Posts: 640
Images: 3
Quote:
Originally Posted by Dominik Seibold View Post
Each of two 50p-frames becomes one field of a 50i-frame. But one field has got half of the resolution of one 50p-frame, so you can add every two rows of the 50p-frame to one. And that's vertical box-low-pass-filtering with 6db-gain. ;)
Yes, of course. Would be a nice idea to stack lines (which would also give 6dB gain) but the time difference between fields has to be maintained.
Serena Steuart is offline   Reply With Quote
Old November 14th, 2008, 06:19 AM   #33
Major Player
 
Join Date: May 2008
Location: Nuremberg, Germany
Posts: 285
Quote:
Originally Posted by Serena Steuart View Post
Yes, of course. Would be a nice idea to stack lines (which would also give 6dB gain) but the time difference between fields has to be maintained.
The time-difference is maintained, because fieldA comes from frame1 and fieldB from frame2.
Assume you are creating a top-field-first interlaced frame out of two consecutive frames frame1 and frame2, then:
The lines 0, 2, 4, 6,... (field-A/even) of the interlaced frame are the lines 0+1, 2+3, 4+5, 6+7,... from frame1 and the lines 1, 3, 5, 7,... (field-B/odd) of the interlaced frame are lines 1+2, 3+4, 5+6, 7+8,... from frame2.
If frame1=frame2 (nothing moved), then the lines 0, 1, 2, 3,... of the interlaced frame are the lines 0+1, 1+2, 2+3, 3+4,... of frame1(=frame2). That's frame1 filtered with the kernel (1, 1)T (T=transposed), also called box- or mean-filter of dimension 1x2 with an amplification of 2 (=6db).
Dominik Seibold is offline   Reply With Quote
Old November 14th, 2008, 05:20 PM   #34
Major Player
 
Join Date: Jun 2006
Location: Studio Alnitak, Melbourne, Victoria, Australia
Posts: 640
Images: 3
That was understood. I was commenting on my proposal to stack corresponding lines from successive frames, which cannot work because the time difference between frames must be the time difference between fields. But thanks for explanation, anyway.
Serena Steuart is offline   Reply
Reply

DV Info Net refers all where-to-buy and where-to-rent questions exclusively to these trusted full line dealers and rental houses...

Professional Video
(800) 833-4801
Portland, OR

B&H Photo Video
(866) 521-7381
New York, NY

Z.G.C.
(973) 335-4460
Mountain Lakes, NJ

Abel Cine Tech
(888) 700-4416
N.Y. NY & L.A. CA

Precision Camera
(800) 677-1023
Austin, TX

DV Info Net also encourages you to support local businesses and buy from an authorized dealer in your neighborhood.
  You are here: DV Info Net > Sony XAVC / XDCAM / NXCAM / AVCHD / HDV / DV Camera Systems > Sony XDCAM EX Pro Handhelds

Thread Tools Search this Thread
Search this Thread:

Advanced Search

 



Google
 

All times are GMT -6. The time now is 01:37 PM.


DV Info Net -- Real Names, Real People, Real Info!
1998-2017 The Digital Video Information Network