Alan Roberts looks at the challenges of testing Cameras in a world where there are UHDTV, HDR,
large format cameras and a number of other combinations which do not fit previous experience.
Do the modern ways of “Tiering” cameras get the best pictures
– and how do you test a modern HDR camera beyond EBU R118?
Camera testing used to be easy - a camera would arrive at Kingswood Warren, I'd play with it for a while, often days or weeks, then write down what I'd found. That meant settings I'd found that made nice pictures for a variety of purposes. Then I retired and it all changed.
It became necessary to standardise what I did, because I'm not getting any younger and will have to stop at some point. That was how EBU Tech.3335 came about, a record of what I do and how I do it.
But other things were changing too, and the BBC no longer wanted to run a 'BBC approved' list of cameras, so we wrote EBU R.118 as a parent document for Tech.3335, and launched the idea of 'Tiering'. Until then, decisions on whether cameras were suitable for broadcast were largely subjective, now there were rules.
The limiting values for resolution, aliasing, and noise were all set in the early days of HDTV broadcasting in the UK, but again it's all changing. Now we have UHDTV, HDR, large format cameras and a number of other combinations which aren't properly dealt with in R.118.
How to deal with all that is a real problem, since these days the emphasis is much more on where in the Tiering system a camera stands, rather than finding some best settings.
Getting this wrong can have serious effects on a company's reputation, and this is having a major effect
on testing, because some manufacturers refuse to have cameras tested,
while others insist on editing the reports, neither of which is satisfactory.
How to get around all this requires some nifty footwork and diplomacy
- I'm reasonably good at it, but it gets harder with every camera test.
Alan Roberts joined the BBC’s R&D Department in 1968 as a Research Engineer, and worked on a wide variety of projects, including standards conversion, teletext, and digital video processing and surface-wave device fabrication, before specialising in colour science and production technology.
He was part of the team that worked on the Eureka95 HDTV project and represented the BBC
on EBU and Eureka committees as a colour scientist.
From this HDTV work in the 1980 and 90s he developed the “film-look” favoured by drama and wildlife programme-makers, devising ways to use the new technology to lower production costs without compromising quality.
Now in retirement, he continues as a consultant on colour science and TV matters, advising manufacturers and programme-makers on TV developments. He's also the only person to make scientific camera tests independently, and has been behind the development and standardisation of the TLCI (Television Lighting Consistency Index) which is now widely used to characterise luminaires for television.
You can read some of his work over the years for the EBU
Ericsson Broadcast and Media at Ealing Plaza is a short 10 minute walk from
Ealing Broadway station National Rail, Central and District lines.
Turn left outside the Station and the Right into Ealing Broadway / Uxbridge Road past Christ the Saviour church – cross to the south side of the road at the pedestrian lights outside the Town hall and continue west wards past the Police Station – Ericsson is in the building just after the Travelodge which has a small Ealing Plaza Totem and a set of arches (just before the bus stop for “E busses”) See map
If you want to travel by bus from Ealing Broadway – turn left out of the station cross the Broadway by The North Star and turn left eastwards across Windsor Road and a parade of shops to the bus stop. Get any bus 207 427 83 but NOT the Express 607 get off at the second stop Ealing Police station Stop P and walk westwards past the Travelodge to the next building .
Street Car parking in Central Ealing is never easy – But there is parking available in Mattock Lane which is one road south from the Uxbridge Road. This is one way west bound at its west end so you need to approach from the St Mary Road / Bond Street / High street round about.
If you park almost immediately and then got up the Barns Pickle Alleyway (a house east of Clifton Lodge school) to the Uxbridge Road and turn left past the Police action – Ericsson is in the building just after the Travelodge which has a small Ealing Plaza Totem and a set of arches (just before the bus stop for “E busses”)
If you cannot find a place by the time you have just beyond the Questors theatre (where right angle parking starts) – drive on until just before the end of right-angle parking – park there and walk along Mattock Lane right into Covington Road and Right again east bound on the Uxbridge Road – Ericsson at Ealing plaza is at the First Bus stop you see look for the totem and arches, see map