shutter on or off - Page 2 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 13th, 2008, 11:07 AM   #16
Inner Circle
 
Join Date: Aug 2006
Location: Poland
Posts: 4,086
Quote:
Originally Posted by Dominik Seibold View Post
Sorry, but you are wrong. 720/50p with shutter-off gives 1/50-shutter.

No, the slowest selectable shutter-speed depends on your framerate. But it's always faster than 1/fps or 360, because else the electronic shutter wouldn't have a job to do and then it wouldn't make any difference if it is turned on or off.
I stand corrected, Dominic (I don't have my EX1 with me at the moment, as it's with the Prime Support for an overhaul) - with 720/50p, it should be 1/50th, same as the fps.

As to the slowest selectable shutter speed, I only meant standard shutters - not the SLS, or EX Slow Shutter.
__________________
Sony PXW-FS7 | DaVinci Resolve Studio; Magix Vegas Pro; i7-5960X CPU; 64 GB RAM; 2x GTX 1080 8GB GPU; Decklink 4K Extreme 12G; 4x 3TB WD Black in RAID 0; 1TB M.2 NVMe cache drive
Piotr Wozniacki is offline   Reply With Quote
Old November 13th, 2008, 11:18 AM   #17
Major Player
 
Join Date: May 2008
Location: Nuremberg, Germany
Posts: 285
Quote:
Originally Posted by Piotr Wozniacki View Post
As to the slowest selectable shutter speed, I only meant standard shutters - not the SLS, or EX Slow Shutter.
I just tried all standard-framerates and got that result:
fps slowest-shutter
24 1/32
25 1/33
30 1/40
50 1/60
60 1/60
Interestingly at 60fps the slowest selectable shutter-speed equals the framerate.
Dominik Seibold is offline   Reply With Quote
Old November 13th, 2008, 11:45 AM   #18
Inner Circle
 
Join Date: Apr 2006
Location: Wales
Posts: 2,130
Quote:
Originally Posted by Serena Steuart
Perhaps you're saying that 50i is actually 50P and the fields for 50i are derived from alternate frames?

Exactly

Are you sure about that? 1080/50i can't be 1080/50P and fields derived from those frames 'cos the camera can't do 1080/50P. Surely 50i is derived from 25P, with alternate lines extracted to make 2 fields.
Steve
Steve Phillipps is offline   Reply With Quote
Old November 13th, 2008, 11:46 AM   #19
Regular Crew
 
Join Date: Jan 2007
Location: Estonia
Posts: 113
Shutter Speed

As i understand,25p with ''shutter off ''means 1/25 th shutter.And because of that indeed lowest shutter setting with ''shutter on'' is 1/33.you can see it if u set at 25 p shutter on or off..picture much brighter with ''shutter off''..

RR
Raul Rooma is offline   Reply With Quote
Old November 13th, 2008, 12:28 PM   #20
Major Player
 
Join Date: May 2008
Location: Nuremberg, Germany
Posts: 285
Quote:
Originally Posted by Steve Phillipps View Post
1080/50i can't be 1080/50P and fields derived from those frames 'cos the camera can't do 1080/50P.
Yes it can! It can't bring it on the sxs-cards, but it captures and processes it.
Quote:
Originally Posted by Steve Phillipps View Post
Surely 50i is derived from 25P, with alternate lines extracted to make 2 fields.
Even if the sensors would support temporal delayed odd (or even) rows, it's not a good idea, because then vertical low-pass-filerting wouldn't be possible, so it would flicker a lot on interlaced screens because of the very good MTF of the sensors+lens (the sensors don't have an appropriate optical low-pass-filter, so progressive images are very sharp). And observation shows, that it does vertical filtering on the whole 1080-rows-frames.
And what about 720/50p? If it would be derived from 1080/50i, then there would be deinterlacing-artifacts.
Dominik Seibold is offline   Reply With Quote
Old November 13th, 2008, 12:39 PM   #21
Major Player
 
Join Date: May 2008
Location: Nuremberg, Germany
Posts: 285
Quote:
Originally Posted by Raul Roma View Post
As i understand,25p with ''shutter off ''means 1/25 th shutter.
Yes. To be more exactly, shutter-off means the additional electronic shutter is turned off. Then the exposure time is just the result of the periodic readout and reseting of the pixels, which depends only on the framerate.
Dominik Seibold is offline   Reply With Quote
Old November 13th, 2008, 12:43 PM   #22
Inner Circle
 
Join Date: Apr 2006
Location: Wales
Posts: 2,130
Not arguing with you Dominik, but where did you find out that the EX can do 1080/50P? I thought that was just the F23. Surely if the sensor could do it then it could feed it out of HD SDI and with the Flash XDR you'd have an F23/SR kit (more or less!) for 5000 instead of 100,000.
Steve
Steve Phillipps is offline   Reply With Quote
Old November 13th, 2008, 12:54 PM   #23
Major Player
 
Join Date: May 2008
Location: Nuremberg, Germany
Posts: 285
Quote:
Originally Posted by Steve Phillipps View Post
where did you find out that the EX can do 1080/50P?
I read it somewhere, but I can't remember where. But more importantly it makes perfectly sense and matches perfectly with all of my experience.
Quote:
Originally Posted by Steve Phillipps View Post
Surely if the sensor could do it then it could feed it out of HD SDI and with the Flash XDR you'd have an F23/SR kit (more or less!) for 5000 instead of 100,000.
For sure it can be hacked. But why doesn't Sony offer it out of the box together with recording of 4:2:2 and 50MBit/s? And why do I have to use these ridiculously overpriced sxs-cards for the little throughput of 4 MByte/s, of which almost every other flash-memory out there is capable of? Hmm, I guess it could be concerned with their marketing-strategy. ;)
Dominik Seibold is offline   Reply With Quote
Old November 13th, 2008, 01:12 PM   #24
Inner Circle
 
Join Date: Apr 2006
Location: Wales
Posts: 2,130
I agree with your sentiments. I've got a PDW700 and wonder why they won't put 160 mb/sec I frame on it as seeming the mpeg used is capable of it as it's the same one used by the Flash XDR.
Still very dubious about the 1080/50P though, AFAIK it certainly does not come out of the HD SDI. Having said that, my PDW700 apparently has the same chip as the HDC1500 studio camera and that can do 1080/50P which mine can't so maybe it's a similar situation?
Steve
Steve Phillipps is offline   Reply With Quote
Old November 13th, 2008, 02:17 PM   #25
Major Player
 
Join Date: May 2006
Location: Tampa, FL
Posts: 596
Quote:
Originally Posted by Dominik Seibold View Post
And why do I have to use these ridiculously overpriced sxs-cards for the little throughput of 4 MByte/s, of which almost every other flash-memory out there is capable of?
I'm waiting for that firmware upgrade that let's me overcrank 1080 24p to 60p! Okay, I'm not exactly holding my breath.
__________________
Sony EX3, Vegas 9.0 64bit, Windows 7(64), Core i7, 12GB, RAID1 & 0, HotSwap SATA, 30" LCD(2560x1600)-GTX285 & 24" LCD(1360x768)-7800GT
Ted OMalley is offline   Reply With Quote
Old November 13th, 2008, 04:12 PM   #26
Major Player
 
Join Date: Jun 2006
Location: Studio Alnitak, Melbourne, Victoria, Australia
Posts: 640
Images: 3
Quote:
Originally Posted by Dominik Seibold View Post
50i also gives higher sensitivity, because the 50i-setting adds gain, to exploit the lower noise-level caused by the vertical low-pass-filter for reducing flicker.
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. This is how we do it in astronomy. I'm very wary of technical arguments based on "I read it somewhere". References please.

EDIT: While my point may seem "aggressive", it arises from long experience in technical discussions where difficulties often arise because people fail to differentiate between what they think and what they know. It is extremely important to make clear what is fact and what is deduced or thought to be so.

Last edited by Serena Steuart; November 13th, 2008 at 06:55 PM. Reason: to add background
Serena Steuart is offline   Reply With Quote
Old November 13th, 2008, 05:57 PM   #27
Major Player
 
Join Date: May 2006
Location: australia
Posts: 407
Hi People,

I just wanted to get back to the subject, if i have the camera set to 720p50 and the shutter off, is the shutter speed 1/50 ?

I have tried both setting and can not seem to see the difference, any one have a idea what is better ?

rob.
__________________
Rob.
www.rpbproductions.com
robert@rpbproductions.com

HD101/G5 Mac/4gig Ram/1TB HDD/30" Cinema Display/FCP.
Robert Bale is offline   Reply With Quote
Old November 13th, 2008, 06:47 PM   #28
Major Player
 
Join Date: Jun 2006
Location: Studio Alnitak, Melbourne, Victoria, Australia
Posts: 640
Images: 3
Yes, shutter off when shooting progressive 50P is 1/50 sec. However that is not stated in the user manual and in accordance with my note above I add "I believe that to be so".
Serena Steuart is offline   Reply With Quote
Old November 13th, 2008, 09:31 PM   #29
Major Player
 
Join Date: May 2006
Location: australia
Posts: 407
Thanks for your comments.
__________________
Rob.
www.rpbproductions.com
robert@rpbproductions.com

HD101/G5 Mac/4gig Ram/1TB HDD/30" Cinema Display/FCP.
Robert Bale is offline   Reply With Quote
Old November 13th, 2008, 10:07 PM   #30
Major Player
 
Join Date: Jun 2006
Location: Studio Alnitak, Melbourne, Victoria, Australia
Posts: 640
Images: 3
OK, I've made some measurements. At 25P shutter off is 1/25. At 720/50P the default shutter is 1/60 (shutter on), which may be the reason you could see little difference between on/off. Shutter off is 1/50. I suppose I should repeat for 50i.

edit: yes, 50i shutter off is 1/50.

Last edited by Serena Steuart; November 13th, 2008 at 10:42 PM. Reason: 50i
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 10:19 AM.


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