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Are these HD production trucks set up to do just one of the two formats, 1080i or 720p, or can they easily be setup to do both formats? The reason I ask is that I noticed the Army-Navy game is on the same weekend as an Eagles home game...but the Eagles game will be on FOX. I realize that more than likely this game wont be in HD on CBS, Im just wondering if it would be at all possible....seems like it would be really nice to have one HD truck do two HD games :).
 

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Most are 1080i. I have never heard of a dual standard truck but all the equipment does exist to build one albiet at a much higher cost. A 1080i/60 and 1080/24p truck would be fairly easy to have these days as most 1080i equipment can also do 1080/24p.


Why would anyone ever shoot events in 24P? Well for live sports, it would not be desirable but for concerts and other entertainment events, it has the ability to convert seamlessly to any world video format without aritifacts and even back to film. 1080i/60 can't do that as seamlessly.
 

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I think that most trucks will either be 1080 or 720 - a result of the differing camera image scanning resolutions and the display formats.


In the days of PAL and NTSC analogue or 576/50i and 480/60i production it was very unusual to find a multi-standard production truck (though some did exist) - and multi-standard broadcast cameras were pretty much unavailable - as the image scanning resolutions were different.


However with 1080 and 720 there are now common image formats across field-rates, meaning that multi-standard cameras are a reality.


In Europe a number of trucks are switchable between 1080/24p, 1080/25p, 1080/30p, 1080/50i and 1080/60i - with 50i being used for domestic sports and productions where "video" would typically have been used, whilst 24p or 25p is used for situations where "film" or reduced field-rate video would have been used in SD situations.


The field-rate issues are much easier to cope with than the differing number of horizontal scan lines - which are the same across field rates.


HOWEVER - Thomson's LDK 6000 is switchable between 1080 and 720 scanning I believe (and across field rates) - so it may be possible to build a switchable 1080/720 truck - though I would imagine monitoring (and all the boring OB truck stuff that is actually vital, like SD routing for monitoring/commentary/courtesy feeds etc. may be more of a hassle?)


(How do Thomson - once Philips once BTS - do this? Well their CCD scanning sensor is actually 1920x4320 - with 4 lines being grouped together for 1080 line scanning and 6 for 720 line scanning. They have a similar technique in SD for providing 16:9 and 4:3 images of the same horizontal width - whereas most other manufacturers fix the height - meaning lens angles change in aspect ratios requiring a range extender to compensate)
 

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A few of the newer trucks carry cameras that are multi-format, such as the LDK 6000 World Cams mentioned above (Multi format 1080p24, 1080i30 or 720p60). NMT's HD-4 is one according to their website (NMTV.com) These trucks can operate natively in any one format at a time. I don't know what it takes to switch formats.
 

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Trucks using Sony MVS-8000A switchers can control multiple switcher processors for several formats through Control Lan functions. Cameras change format with internal presets and auto setup, monitoring is autosetup also. Test signals are sent through the chain to initiate format changes. It takes a little time to change format, but is SOP for a busy crew.

Just went through a Sony Switcher class.

GT
 

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Also trucks using the Sony HDC-900/950 family cameras and the HDCU-900 camera control unit (like the HDNET trucks) can take a option module (HKCU-904) for 720P output.


Ernie
 

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Quote:
Originally posted by ernie
Also trucks using the Sony HDC-900/950 family cameras and the HDCU-900 camera control unit (like the HDNET trucks) can take a option module (HKCU-904) for 720P output.


Ernie
Though presumably this is a downconversion in the CCU to 720p from the 1080i (or 1080/24/25/30p) output from the camera rather than the camera itself running in 720p native?


AIUI the main difference between the Thomson/Philips cameras and everybody elses is the concept of DPMS - whereby you have many more lines in the camera sensor than the output standard and aggregate - whereas other cameras have the same number of lines as the output standard, and downconvert for output in other standards?


This allows you to use the Sony cameras in a 720p production environment, rather than using a 1080i or 1080p production environment and downconverting the output. (Allowing 720p graphics and VT inserts for example) However it IS a conversion - rather than a native acquisition?


(Of course you could argue that the Thomson/Philips system is a conversion from 4000ish lines to 1080 or 720...)
 

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Quote:
Originally posted by George Thompson
Trucks using Sony MVS-8000A switchers can control multiple switcher processors for several formats through Control Lan functions. Cameras change format with internal presets and auto setup, monitoring is autosetup also. Test signals are sent through the chain to initiate format changes. It takes a little time to change format, but is SOP for a busy crew.

Just went through a Sony Switcher class.

GT
Presumable the multiple switcher control is more to allow separate SD and HD mixes - say to feed in-vision screens using an SD mix whilst keeping the HD mix for the programme chain?


Or is it conceivable that simultaneous production in 1080 and 720 (rather than conversion from one to the other) would be required?


Pressumably standard switching is done on a production by production basis - so a single HD standard is used for a given job? But different jobs for a truck might require different standards?


Out of interest - how do monitor stacks cope with the 1080/24/25/30p signals ?


Assuming interlaced CRTs are in use I had kind of assumed that the progressive stuff would be monitored in 50i or 60i - with the 24p stuff either 48i or 3:2 pulldown 60i? I had kind of assumed that monitors don't display a 50p or 60p signal progressively, and 25p/30p would be too low a rate for a progressive signal.


I know some trucks use progressive plasmas for some monitoring - but I would assume that the camera guys get a high quality CRT for colour balancing etc.? (I know a common complaint in early European trucks was that some production monitoring - even some vision monitoring - was SD not HD...)
 

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Quote:
Originally posted by sneals2000
Though presumably this is a downconversion in the CCU to 720p from the 1080i (or 1080/24/25/30p) output from the camera rather than the camera itself running in 720p native?


AIUI the main difference between the Thomson/Philips cameras and everybody elses is the concept of DPMS - whereby you have many more lines in the camera sensor than the output standard and aggregate - whereas other cameras have the same number of lines as the output standard, and downconvert for output in other standards?


This allows you to use the Sony cameras in a 720p production environment, rather than using a 1080i or 1080p production environment and downconverting the output. (Allowing 720p graphics and VT inserts for example) However it IS a conversion - rather than a native acquisition?


(Of course you could argue that the Thomson/Philips system is a conversion from 4000ish lines to 1080 or 720...)
Yes, it is a conversion and unfortunately from 1920x540/60P mode. Never the less, the truck would be outputting 720p or 1080i, which was the original question.


See:

http://pro.sony.com.hk/product/spec/...e/MK7348V4.pdf


Ernie
 

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When ESPN says they want every stadium to go to 1080p, that's why. Because it's an easy conversion to 720p (maintaining the P) or 1080i. Of course, everybody on here wanted 1080p at their doorstep, but that's not what they had in mind (at least not right away).


I have seen some 720p broadcasts that definitely suffered from interlacing artifacts. They were probably downconverted from 1080i cameras. Having 1080p at every stadium would solve the problem.
 

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Quote:
Originally posted by PRMan
When ESPN says they want every stadium to go to 1080p, that's why. Because it's an easy conversion to 720p (maintaining the P) or 1080i. Of course, everybody on here wanted 1080p at their doorstep, but that's not what they had in mind (at least not right away).


I have seen some 720p broadcasts that definitely suffered from interlacing artifacts. They were probably downconverted from 1080i cameras. Having 1080p at every stadium would solve the problem.
Yep - though 1080/60p (which presumably is the suggested standard) will be a real bandwith hog for things like VTRs and radio links etc. (Is it in spec for HD-SDI - or do you have to run 2 vision feeds for a 1080/60p source? With effectively both carrying data at 1080/60i rates)
 
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