BBC News Rebrand - This Monday

Racking, or vision operation, is the process of setting up, and dynamically altering, the performance of a studio or OB camera.

It is the process by which you set the black level, white level, colour balance, aperture correction and detail (how much artificial sharpening is added to counteract the limitations of the CCD sensors and lenses) as well stuff like gamma, knee etc.

Racking can make a huge difference to picture quality - from someone's jacket changing colour between cameras because the cameras are not "matched" properly, to a jacket going from deep black with no detail to light grey (because the black, black stretch and gamma are not set correctly), to highlights being burned out (because the knee isn't correctly set), to contrasting areas having dark/bright edges around them (because excessive aperture correction and detail settings are being used)

Lighting can add and remove years from talent - but so can racking...

Many people comment on "good lighting" and "bad lighting" - but often the difference is more in the racking of the cameras.

News 24 have nobody to dynamically rack their cameras - and even in the wider industry there are fewer and fewer people who actually know what they are doing when it comes to this - which is apparent when you watch other programmes. It is a problem for the industry - partially caused because the cameras themselves are so much more reliable these days they don't need to be lined up daily by people who know what they are doing.

I've got a "dummies guide" to racking on my Athens photos site - http://home.vis-is.co.uk/athens/data.php , as my main job at the Olympics was to provide racking control of camera over radio link.

Racking is seen as more important than ever in live sport, which kick started the development of radio racking systems, so that all the cameras can be set up from one point, rather than taking up lots of comms time talking a camera op into getting the same settings as the cabled cameras. But as you say noggin, with the stability of the kit available these days, and static conditions as found in studios, the vision engineer is one less person to have to pay for.

When I did a TV technology course at Wood Norton, we had to ask the tutor to do a special additional session during part of lunch on camera line up because it was not in the syllabus. And since it was rushed it was not very in depth - a) point camera at line up card b) press auto set up buttons c) if picture looks really bad then get the scope out and do it manually (and I know you are supposed to measure the light level and match it up - but they couldn't find a working light meter at short notice)

After that I would in no way consider myself an expert in racking, but I suspect I know more than nearly every World Service video producer or SM that uses the Bush studios. That isn't a negative reflection on them, because they have never been trained to set a camera up. And this is the problem, the maximum people get taught on line up these days is to point a camera at a bit of white card and press the auto white balance button. And those are the well trained ones. But because the modern cameras are so forgiving they still produce acceptable results proving that a full camera line up is not necessary, so the current training system is adequate - right? And don't get me started on the 'fix it in post' attitude.



You tend to see a lot of the above on material shot outdoors, especially DV cam stuff for news or 'reality' type shows where it does not go back to an OB truck for racking. Since outdoor light levels can go all over the place in the space of a minute I would give the benefit of the doubt. But inside a controlled studio environment there is NO excuse.

Whose job is it to rack the cameras in a news studio though? And since the cameras are remote controlled there's no cameraman seeing a zebra in the viewfinder who can warn the gallery the CCDs are saturating.

You can't - technically - rack something once it has been shot. Racking works prior to the generation of the video signal - so ensures the full signal capacity (i.e. all the bits) containg accurate video information.

When you have to "fix it in post" that is called grading (legacy BBC term "TARIFing" - from Technical Apparatus for Rectification of Inferior Film) - you can improve things, and in some cases fix things, but in some cases - such as crushed blacks, or peak whites or massively incorrect colour balance, there is no data to rescue as it has been lost.



With single camera stuff it is much easier in some ways - as you are shooting everything on the same camera - so at least it matches. In a studio you have to ensure the cameras are racked so that they match each other.


In small studios it is usually the Lighting Director, who may also remotely control the camera framing, and in some cases position on the floor. In larger studios this combined role is split - often with a separate LD and Vision Operator - though the VO may well be racking and remotely framing at the same time in studios with remote cameras.


Zebras are irrelevant in a studio - the camera operator on the floor (if there is one) doesn't rack the cameras or do anything other than frame and focus. The racking is controlled remotely from the camera control unit (or the remote control panel connected to it) via the triax, fibre or multicore cable (or radio links - which have allowed racking since the days of the Philips minicam in the early 1970s - and which generate the modern triax system concept)

Zebras are useful for a location camcorder camera operator who needs to have a quick guide to picture exposure so they can set their iris correctly - but in a studio you have decent picture monitors, not just a small viewfinder, as well as a waveform monitor and vectorscope (often combined these days). That said - most decent racks operators use the scope only as a guide and use their eyes and properly lined up Grade 1 (or just below Grade 1) picture monitors - monitoring all the cameras on the same monitor by quickly switching between the cameras to compare them.

In large studios and OBs you will often find junior vision operators racking cameras in terms of black level and exposure, with a vision supervisor dynamically controlling the colour balance and aperture correction/detail levels to ensure high quality pictures.

Yep - ISTR that the first colour camera that could be remotely racked over radio links was the original colour handheld Philips minicam (developed for CBS by Philips in the US - and then converted to PAL just for the BBC) - developed in the late 60s. The radio system that allowed remote racking for it was also capable of being carried on a cable that also carried power - and thus Triax was born AIUI.

Philips continued to have radio control over their cameras through the 70s (I believe both the LDK5 and the LDK14 aka LDK514 could be racked when working via microwave rather than triax) - however the Japanese manufacturers never really caught on to this as a requirement.

As the single person microwave links appeared in the late 80s, allowing remote radio links to be mounted on the camera back, making them far more useful and far more dynamic, and thus far more in need of radio racking, a system that required remote data control was needed. BBC OBs designed their own system in-house (RACS I think it was called) - using a 300 baud modem radiating data to all cameras via an audio talkback circuit - which was based on an Acorn Archimedes (by then the BBC Micro at the time) and would also interface to the Sony RCPs allowing radio cameras to be racked seamlessly with their cabled counterparts.

Wow - talk about the pot calling the kettle black.

I think most people would agree that noggin is undoubtedly one of the most valuable members of the forum - he takes a lot of time to explain things in great detail, giving information that is of real interest to both casual visitors and seasoned industry professionals.

I, for one, have never thought that noggin was arrogant - he actually knows a lot more than most of us here, and it's great of him to share that knowledge with us.

You on the other hand come across as arrogant and confrontational in the vast majority of your posts - perhaps you should consider sorting out your own attitude before pointing out flaws in others.

New elements appearing on BBC News website...

http://newsimg.bbc.co.uk/nol/shared/img/v3/icons/video_live.gif
http://newsimg.bbc.co.uk/nol/shared/img/v3/icons/audio_text.gif

Is blue to be part of the new look BBC News?

Doesn't really look like that shade of blue fits on the current homepage it has to be said.

But I thought the relaunched site would essentially do away with these "pop-up prompts" to watch a video, instead favouring embedded video in the iPlayer style?

I would be surprised if it were a major element of the video branding.

All the research suggests that significant amounts of blue are cold and distancing, and blue also suffers as an accent colour when carried by component video systems (as it is lower luminance than green and red) as it isn't carried as cleanly as other colours.

Of course there is nothing to stop it featuring in the wider brand - online etc. - where there are different issues at play.

If you are ever looking at chosing a colour scheme for graphics for digital TV - including HD - that uses 4:2:2 or 4:2:0 8 bit video it is worth knowing (though it is surprising how many designers don't) to not extensively use a predominantly blue palette - as it suffers far more through the transmission chain than red and green.

If you've ever seen a full-frame blue gradient - a bit like the 12 yard endboard - you'll know what I mean.

(In SD systems - HD is slightly different - Blue only contributes 11% of its information to the high resolution luminance signal, whilst green contributes 50% and red 39% - and this can mean that blue content appears to band /posterise and look softer and blockier)

I don't understand, how are they any different, to the ones e.g. below?

http://news.bbc.co.uk/nol/shared/spl/hi/pop_ups/07/in_pictures_10_years_of_the_bbc_news_website/img/10.jpg

(Given maybe, a slight change in the brightness of blue)

I think the embedding is more to do with pre-recorded video. Live streaming remains as a pop-up system AIUI.

This from the BBC Internet Blog:

News and Sport Embedded Media

"There will be some exceptions to using the EMP for now, generally where the media experience is heavily stylised or embedded within interactive games. We are also not moving live streams over to Flash yet, but aim to do so by the summer."

Full article here