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EMI 2001 camera query - dark green tint on BBC shows?

 
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EMI 2001 camera query - dark green tint on BBC shows?

Post by AidanLunn » Thu May 05, 2016 7:14 pm

Apologies if this is the wrong kind of topic here, as it mainly deals with a vintage piece of broadcast kit rather than a vintage domestic TV receiver, but this is something I've noticed when watching various (colour, of course!) programmes made over the years that have definitely used these cameras on a variety of TV sets (not just vintage colour sets, modern flat panel sets as well).

My question is, why is it only BBC programmes that were made using these cameras that have a distinct green tint to any parts of the image that are supposed to be dark or black? I've seen this green tint on BBC programmes like Dad's Army, Steptoe, Colditz, even up to programmes in the 80s made using these like Hi-de-Hi and The Young Ones.

BBC programmes made using Link 110s and 125s don't have this issue, and ITV programmes made using 2001s don't have it either - black looks as black as a TV set with black level AGC can produce. I've seen this on programmes like "Callan" and "Public Eye" from Thames, "Please Sir" from LWT, "Crossroads", "TISWAS" and "Thriller" from ATV/Central, "Nearest and Dearest" from Granada and "Rising Damp" from Yorkshire - a good cross-section of ITV companies (using the IBA's technical standard's of course, which did differ slightly in areas like gamma compared to those of the BBC) that all used these cameras that - whilst there were other large-selling colour cameras like the Marconi MkVII and that Philips/Pye/Peto-Scott one - were made when the 2001 was the de facto colour camera for British broadcasters that made the majority of large-scale, nationally-seen productions (BBC, ATV/Central, Granada, LWT, Thames and Yorkshire).

To compound my confusion, early colour BBC series like Up Pompeii (1969-1970), Doomwatch (1970-72) and earlier Monty Python don't have this green tint either - like the ITV examples above, black looks as good as black level AGC can get, and not dark green.

So why just BBC productions and why only BBC productions using these cameras from about 1972/73 until the end of their working life? (They were gradually phased out at the BBC between about 1977 and 1991.)

Did - as I suspect - the BBC made modifications to their examples of these cameras to improve the picture, which looked good on 1970s TV sets but didn't translate too well when the BBC were transferring their archive of 2" and 1" videotape material to more modern (digital) formats? I can't imagine the BBC of the 70s wanting their colour pictures to be of a very high standard allowing green tints to be seen on your average Decca Bradford or ITT CVC5.

I'd thank anyone with more knowledge of the circuitry of these cameras and of the attitude of the BBC towards modifying them for answering this question, it's puzzled me for quite a while, but I can't work out an answer to that question - why only BBC productions after about 1972 using these cameras have this green tint. Largely absent (it's during 1972 that this green tint seems to creep in) on BBC productions before this, completely absent on BBC productions using other tubed colour cameras and on all ITV productions I've seen using these 2001s.

Apologies for rabbitting on - I could probably have simply condensed this question, but I like to put as much information into questions about what I think are fascinating subjects (others might consider them boring) like this so that others don't need to ask, e.g. "Have you seen this on ITV productions, other BBC productions using different camera models?" etc.

For those who don't know what an EMI 2001 looks like, it's the "1970s Top of the Pops" camera. These things:

http://www.golden-agetv.co.uk/img/portfolio/36p.JPG



I suppose asking this question might also benefit people on here when watching period BBC programming on vintage colour TVs that might think their TV has developed a green tint on blacks - it's not your set, it's whatever the answer to the question I'm posing is.

EDIT: I think I also saw the green tints mentioned on Martin Kempton's excellent website (under title "potted history of early colour cameras"), but I can't find it now, so I know I'm not the only one to notice this.

 
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Re: EMI 2001 camera query - dark green tint on BBC shows?

Post by occiput » Fri May 06, 2016 3:37 pm

An ex-colleague has drawn this thread to my attention.

The EMI 2001 cameras at Television Centre and elsewhere in the BBC were subject to a number of modifications over their service lives. In the main, the purposes of these were, in no particular order: to improve performance, to add extra operational functionality, to make the cameras easier to line up and/or maintain, to improve reliability, and to suit BBC operational and engineering practices.

If I recall correctly, the last approved modification was to add viewfinder mix operation from the pan-bar. At this point, a decision was made that any advantage accruing from further modifications was likely to be offset by a reduction in reliability and availability, due to the age of the wiring in the heads and camera control units.

During the course of a production day, a studio's complement of cameras were accurately aligned and matched for fidelity of colour reproduction, under controlled conditions, at least twice. Throughout recording, camera performance was maintained by an Engineer undertaking colour-balancing duties in the Lighting and Vision Control Room, and another monitoring the other engineering aspects of camera behaviour in the Vision Apparatus Room and making adjustments as required. In addition, the pictures produced by the cameras were under close and continuous scrutiny by the Vision Operator, the Lighting and Vision Supervisor and the Lighting Director. Any problems identified by any of these people would receive immediate engineering attention.

In view of this, it would be somewhat surprising if camera defects which apparently passed un-noticed by all these skilled, trained and highly experienced people, using professional monitoring equipment, in the studio at the time of recording, only became visible on domestic equipment some 40 years, and several generations of recording and other post-processing, later. This prompts the question as to why you believe, as you seem to, that the effect you describe is an artefact of camera performance.

Incidentally, I think is very unlikely that the two camera heads shown in the picture to which you link are ex-BBC London Studios. They would certainly not have been used on "Top of the Pops" in the condition shown.

 
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Re: EMI 2001 camera query - dark green tint on BBC shows?

Post by AidanLunn » Fri May 06, 2016 9:57 pm

Thank you for answering, this is most fascinating!

I was surmising that maybe the cause of the green tinge to the image was the result of dubbing the 2" material to D3 or DigiBeta and the transcoders for the more modern format's recorders picking up on an artefact in the analogue signal that a purely analogue playback device - say a Quad VTR - wouldn't pick up. I explain this line of thinking a little further down this post.

The reason why I come to the conclusion that it's something related to the cameras is because contemporaries (in the 2001's later life) like the Link 110s and 125s don't show up the same artefact. Also 2001s used by the ITV companies don't show the artefact at all (although Thames ones seem to be more susceptible to "smearing" on movement than the other ITV companies and the BBCs examples of the 2001). I don't know why I have an eye for this kind of detail in the image, when I'm sure 99% of people wouldn't care, I just do.

People (including myself) have noted that the Links (and the Marconi Mk9s favoured by many ITV companies around this time) produced a slightly brown-tinted colour (more so the Marconis). People who have worked with these models of cameras remember during productions at the time that the images had this tint. So far I have not heard anyone who used 2001s recall seeing a green cast on colour monitors when using them in the studio. Also, I neglected to mention earlier, the above late 70s/early 80s cameras had an *overall* brown tint to the picture, tinting everything in it, including skin colours etc so that e.g. caucasian skin colour looks a little browner or off-colour than it otherwise should do. The green tint on 2001s I am asking about only appears in parts of the picture that are supposed to be dark, the green cast doesn't seem to impact on other parts of a picture - skin tones etc all look perfect. It *looks* as though some kind of green output is superimposed on the black level. I'm sure that's technically not possible but that's what it looks like, if you can imagine the results on a colour TV screen of such an effect.

I'm thinking maybe a modification to the cameras to improve their performance in some respect related to the colourimetry of the camera which didn't produce any side effects on the technology of the time but when it came to transcoding to digital (Digital PAL for D3, Digital component(?) for DigiBeta), the technology for transcoding an analogue PAL/CVBS signal to digital picked up on a very slight difference in the video signal than what they were designed to deal with. Experience has told me that digital technology that converts to digital from analogue only really accepts analogue signals if the analogue signal being input adheres to a very strict set of parameters, even slight deviation from this and you can get odd effects or even no acceptance of the analogue input at all!

In light of not putting this question to others the above is only a theory based on my experience of broadcast technology (mainly University in partnership with the National Media Museum, and using their "backroom" studio equipment, I'm still trying to break into the main industry but a steady job with steady income resulting in a stable bank balance usually blocks me). Nowhere near as much as people like yourself, brianc, Cathovisor and a few others on here and elsewhere, but still a lot more than those who have never operated a vectorscope in their lives :bba

The image isn't taken from Top of the Pops, it's on the "Golden-age TV" recreations website, I used that image as it's the best picture I can find of a 2001 in situ on pedestal. Those are probably supposed to be EMI 2001s pre-BBC viewfinder mod (note the white squares at the side of the monitor are present - these were removed during the viewfinder modification) but in reality I think are ex-ITV models. Apart from ATV's Elstree studios (who used yet another viewfinder mod), generally ITV companies didn't modify their 2001s as frequently as the BBC did. I think this is why whenever I've read stories about someone restoring a 2001, they've preferred an ITV example!

 
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Re: EMI 2001 camera query - dark green tint on BBC shows?

Post by occiput » Sat May 07, 2016 2:53 pm

You now appear to be saying that you think the problem is connected with the PAL signal in some way.

Firstly, PAL and CVBS are not the same thing.

Next, which component of the EMI 2001 camera channel produces a coded PAL signal?

What are the tolerances on the PAL signal at the output of a television studio (BBC spec or IBA CoP will do)?

Which professional video A to D converter(s) produce(s) no output when presented with an out-of-tolerance PAL signal, and how far out of tolerance must the signal be for the converter to reject it?

Why might the fidelity of colour reproduction of second-generation colour cameras such as the Link 110, 125 or Marconi Mk IX differ from that of the EMI 2001 or Marconi Mk VII?

 
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Re: EMI 2001 camera query - dark green tint on BBC shows?

Post by Michael Watterson » Sat May 07, 2016 3:42 pm

In view of this, it would be somewhat surprising if camera defects which apparently passed un-noticed by all these skilled, trained and highly experienced people, using professional monitoring equipment, in the studio at the time of recording, only became visible on domestic equipment some 40 years, and several generations of recording and other post-processing, later.


I can't believe it's the cameras or the source VT. It may have been some madness during transcription by one operator, hence affecting a batch of videos.

 
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Re: EMI 2001 camera query - dark green tint on BBC shows?

Post by occiput » Sat May 07, 2016 5:05 pm

Michael Watterson wrote:
In view of this, it would be somewhat surprising if camera defects which apparently passed un-noticed by all these skilled, trained and highly experienced people, using professional monitoring equipment, in the studio at the time of recording, only became visible on domestic equipment some 40 years, and several generations of recording and other post-processing, later.


I can't believe it's the cameras or the source VT. It may have been some madness during transcription by one operator, hence affecting a batch of videos.


I have the disadvantage of not having seen the effect myself, but with that reservation, I'd say you're more likely to be right than the OP. I have already tried to hint at that, but the hint wasn't taken.

I can be very confident that the pictures wouldn't have left the studio showing the effect to which the OP refers. Between there and a video-cassette or DVD, there is a long chain of electronics and quite a few humans. Distortions can be introduced at many of these stages. This is why I asked the OP why he believed the cameras to be the source. I will be polite and say that I didn't find the answer offered to be very satisfactory.

If the effect is a real one, about which I pass no comment, I have a reasonable idea where I would start to look. However, I'll say no more on this aspect, as it would be unfair to offer even implicit criticism of former colleagues without fuller knowledge of all the circumstances.

 
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Re: EMI 2001 camera query - dark green tint on BBC shows?

Post by PYE625 » Sat May 07, 2016 5:29 pm

AidanLunn wrote:My question is, why is it only BBC programmes that were made using these cameras that have a distinct green tint to any parts of the image that are supposed to be dark or black? I've seen this green tint on BBC programmes like Dad's Army, Steptoe, Colditz, even up to programmes in the 80s made using these like Hi-de-Hi and The Young Ones.



Just to agree that I too have noticed this, but as for any technical reason, I cannot say.
I just enjoy the program on a CRT television (B&O MX7000).
Cannot stand flat screen tv sets, pictures look false and almost animated to me, but that's another subject entirely!

 
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Re: EMI 2001 camera query - dark green tint on BBC shows?

Post by Cathovisor » Sat May 07, 2016 5:45 pm

If you've seen it on the second series of The Young Ones then it definitely isn't the fault of the cameras because they were only made in Link studios; by 1984 only one studio that could take an audience was still using EMI cameras and that was TC1. TC3 was just going out of service with its cameras going to the newly-acquired Elstree 'C': TC5 was still an EMI studio but its size meant you had no chance of mounting a sitcom in it.

In 1984 the TC studio camera complements were as follows:

TC1: EMI 2001 (5, may have been 6, can't remember now)
TC2: Link 125 (4)
TC3: EMI 2001 but OOS from about June (I helped strip it out and transfer the EP5/512 to TC5). It returned with Link 125s.
TC4: Link 125 (5)
TC5: EMI 2001 (4)
TC6: Link 110 (5)
TC7: Link 110 (4)
TC8: Link 110 (5)

 
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Re: EMI 2001 camera query - dark green tint on BBC shows?

Post by occiput » Sat May 07, 2016 6:29 pm

I may well be mistaken about this: it is, after all, a long time ago now, but I have an idea that, remounts aside, all of "The Young Ones" was made somewhere down the Spur end of the corridor. TC8 springs to mind. Link 110s since 1978.

I believe TC6's 2001s went to Bangor, and I know TC7's went to the scanner at the Greenwood. Don't know what happened to TC8's, except that the one in use as a rostrum camera in the Graphics Workshop had a very low head number - 102 or 104 from memory, and I wondered whether it was from TC8.

Going back to the original topic, we have a good deal to be grateful to William of Ockham for, don't we?

 
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Re: EMI 2001 camera query - dark green tint on BBC shows?

Post by AidanLunn » Sat May 07, 2016 8:43 pm

occiput wrote:You now appear to be saying that you think the problem is connected with the PAL signal in some way.


All along I've been trying to make it clear that my thinking is a modification was made to the camera's performance in respect to colour which all pieces of equipment up until (but not including) conversion to digital in the early 90s threw no protests against and broadcast and displayed the image as the BBC intended (as close as was possible on domestic TV sets of the time). Then it gets converted to digital - *if* there is a modification to the colour performance (not the PAL signal - I never *meant* a modification to the PAL or CVBS signals so apologies for confusion) - then there is possibly something at this conversion stage or thereafter that picks up on this camera mod in some way that produced this side effect?

occiput wrote:What are the tolerances on the PAL signal at the output of a television studio (BBC spec or IBA CoP will do)?


I don't have that information to hand unfortunately, but I know from people who have worked for both organisations that there were differences, as mentioned gamma was one. I skipped a couple of your questions as in all honesty I didn't have the information to hand to answer those either.

occiput wrote:Which professional video A to D converter(s) produce(s) no output when presented with an out-of-tolerance PAL signal, and how far out of tolerance must the signal be for the converter to reject it?


This example of no acceptance was taken as an example of digital conversion technology, but mainly as seen on domestic flat panel sets when being input with an analogue source that can be unstable, e.g. a VCR or the RF output of early video games. Even so, if you were to put in something like a 405-line recording into a modern A-D converter, that wouldn't accept it. Might recognise that there is something there but it won't decode it. My point here is that for any analogue to digital converter, the analogue signal has to be in a form that the converter is expecting, if it's non-standard, then it *might* still accept it, but that obviously depends on how out of tolerance the input signal is and the tolerances accepted by the converter. This is assuming in this example there is no TBC, but even then they also have tolerances before they can no longer correct the timebases. Those of us who have tried to put a signal from Betamax or VHS into an Aurora 625>405 converter will have come across this - the Aurora doesn't like the unstable timebase jitter (it has no TBC) of these formats so switches between the input source and the default "no input" image loaded into the flash memory.

I know I've been rabbitting on about timebases here (these are the best real-life examples I can think of), but if an ADC doesn't like a non-standard timebase signal, then who's to say they will always accept a (suspected) slight modification made to the colour performance of a camera 20+ years previously that the equipment of the day didn't throw up any side effects when playing or passing the signal?

occiput wrote:Why might the fidelity of colour reproduction of second-generation colour cameras such as the Link 110, 125 or Marconi Mk IX differ from that of the EMI 2001 or Marconi Mk VII?


Because of the different ways in which they produced the image:

EMI 2001s took the output of the green tube to make the basic image, whilst the luminance tube only supplied fine detail between about 1.5 - 5.5MHz. I did think the fact that they took the green image as the starting point may have been the cause then of course the question is but then ITV examples don't display this.

Theory 2 - Alternatively, it may have been down to the BBC's transcoding equipment or the settings thereof that picked up on this way of generating the image in the transfer stage? Come to think of it that ties in with the "settings" theory that Michael suggested above, though I doubt it was a moment of madness as this has affected most BBC stuff from this period using these cameras that I've seen.

Marconi MkVIIIs even had a different fidelity to 2001s - those used by some ITV companies (I have a fair few programmes from Southern using these cameras in my DVD collection) that make people look tanned, whenever I've seen output from other companies using these the picture looks like black and white one coloured in - which is exactly what it was. The luminance tube output was taken as the starting point then the output from the RG&B tubes added in.

The second generation of colour cameras were (like the Philips PC60 of the first generation) all three-tube designs, which not only introduced a slightly softer image than the 4-tube ones, I've noticed at least also don't give as good skin tones and therefore colour fidelity as the 2001 (this is how I could tell it is only programmes shot using EMI 2001s that have this effect - these second generation cameras have slightly off-colour flesh tones and the resulting images as seen today don't have this green tint).



I don't want to sound brusque, as I only want to make the point clear (ironically the clearest I think I've made it - sorry for any confusion as I was trying to make points that people might have asked if I didn't make them in my speeches above), so to sum up my first theory, I will try it in a series of chronological bullet points:

1) Some EMI 2001s in a studio at, say, TVC, have been in use for some time. They might have had modifications done already and now it is time for an approved modification to their colour performance to be made. The mod is made and they sit awaiting their next assignment.

2) The cameras are lined up, a programme recorded and in the days or weeks following this, possibly edited. The quality of the image at all times is maintained to the best possible standards the hardware of the day can do, as close to BBC spec as possible.

3) The programme is then transmitted, again the playback and transmission hardware is adjusted to the best possible results. The modification made to the cameras makes the image look even closer to BBC spec as previously. At no point in the chain from the image being taken in the camera to the image being displayed on the domestic colour TV set does any piece of hardware throw up any form of protestation against this mod made to the cameras. If this is a programme recorded on Quad, the same goes for any repeat transmissions in the 1980s that may have involved a transfer to and then repeat transmission from 1" C-type format - the programme looks the absolute best the available hardware can display.

4) By stage four, it's the 1990s and D3 and later DigiBeta have been introduced - time for the BBC project of transferring their entire archive of 2" (and 1") format tapes to either of these two newer formats, including the example programme mentioned in stages 2 and 3. First they have to pass the signals from the 2" or 1" machine through an ADC (and other equipment? I was not part of such a project at that time) which lies between the old format and new format machines. In my theory, the snag here is that the transcoding equipment between the machines of the two different formats in a transfer of the programme picks up on this mod made to the colour performance of the camera decades earlier as the colour fidelity the transcoder is *expecting* is not there, instead it is being presented with the modified colour fidelity of a first generation colour camera. This "tinting" might have even happened in the transfer from Quad/1" to DigiBeta, or the transfer of D3 dubs of Quad/1" material made earlier in this project to DigiBeta (i.e. PAL - digital or analogue - to component via YUV 4:2:2 subsampling). I've had to read up on digital video theory again after a gap of a few years, so please forgive me if there are large gaps in my knowledge here, as much of it has been forgotten in the intervening years.

What I think we can all agree on is that if you have noticed this effect, it will have happened in a transfer from one format to another, the programmes would not have been originally transmitted with this green tint in dark parts of the picture. I concur that it could have happened at any stage after the initial transfer in the 90s or 2000s, including when being published to DVD, although I seem to remember seeing this effect on broadcast repeats of programmes even when DVD was still in relative infancy.




The above is just a theory as result of racking my brains trying to find an answer of my own, part of my question here was if I was right, but mainly what exactly is causing to be just these programmes from only the BBC with BBC examples of only the EMI 2001.

I apologise if I'm causing frustration with this theory but I can't see any way of putting this theory clearer than the two times I've tried in this post alone. In the previous posts in an attempt to be as clear and as accurate as possible I've put too much information and thus gone so far and supplied so much info that I might have gone past the point of being as clear and as detailed as I can get and so muddied the waters in my point again.



I'll see if I can find examples of this "green tint in dark parts of the image" then post screenshots here as some do and some don't notice it, it might be better if we were to all actually see what I'm asking about in this thread.

 
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Re: EMI 2001 camera query - dark green tint on BBC shows?

Post by AidanLunn » Sat May 07, 2016 10:32 pm

I have taken some images but just before I do post them, I have found the part of the article on early colour cameras on Martin Kempton's website, but from the way the website was written I can't link to it directly, so I found it by doing a ctrl+F search for "colour casts" on this page: http://www.tvstudiohistory.co.uk/tv%20c ... htm#colour cameras. (There is a space in the URL, curiously, the word "colour" is part of it.)

Although his passage doesn't mention about these colour casts being specifically green, upon actually being on the lookout for these green casts in old programmes, it seems as though they are only visible on some cameras or shots and not others, indeed a few I have seen when seeking out examples just now have very dark blue casts which aren't picked up quite as well by my cameraphone as green ones. So that has blown my theory out of the water, for the thousandth time, apologies for confusion caused. This is just a case of only noticing something when it appears but not noticing when it doesn't when casually watching - actively looking for this effect has made me notice more about it.

I did try loading these into my PC and taking screenshots of the footage with this effect but with the contrast, brightness and colour controls of my flat screen monitor matched as closely with the TV out of my collection I am currently using (this flat panel monitor is not the flat screen I referred to upthread, that was a TV I had access to at one time). But unfortunately the monitor only showed the effect if looked for very closely and so may not have been visible on other people's monitors, however the CRT TV I'm using shows the effect much more clearly (although a bit too well, it's not *quite* this obvious seen through the human eye), so I had to photograph the screen - be aware that as it's an RF-only Thorn TX9, so there is obviously some noise in the picture, but the green tint is unmistakably what I have seen on other sets using less noisier connections than RF, IIRC at one time even on a TV with RGB through SCART. At the moment, apart from a Grundig portable with DIN-style RGB connector for a BBC Micro connection, I have no TV set in my collection with any input other than RF socket. And as two other people - one on this thread and Martin Kempton - a Lighting Director for the BBC at the time - I'm now pretty confident it's not my equipment.

The two BBC programmes that I have taken screenshots from, in case any member has these also and would like to examine for themselves, are the 1975 Christmas special of "Porridge" and the 1976 Doctor Who story "The Brain of Morbius".
Attachments
EMI2001green1.jpg
EMI2001green2.jpg
EMI2001green3.jpg
EMI2001green4.jpg

 
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Re: EMI 2001 camera query - dark green tint on BBC shows?

Post by Cathovisor » Sun May 08, 2016 11:34 am

Aidan,

How we're supposed to make a critical judgment on those poor quality pictures you've posted I do not know.

Please download and install VLC onto your computer, play the DVD on it and use the menu to take snapshots of disc playback.

 
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Re: EMI 2001 camera query - dark green tint on BBC shows?

Post by AidanLunn » Sun May 08, 2016 12:50 pm

As I said in the above post, I have tried that (ironically, using VLC). As my monitor was not showing the effect very well no matter how close I got the picture settings on that as close as I could to my TV's settings, I wouldn't be able to tell if the effect would then be visible to others on here.

There is a green (and now I notice, sometimes a dark blue) tint on programmes using these cameras from the BBC during the 70s and 80s. It seems some people have noticed it and some people haven't at all. I was hoping upthread that my monitor would show the effect but as it doesn't, I can't be confident that other people here would see it - those images I took may be poor quality but they do definitely show a green cast to the image that is not only present on this TV but on others I have tried in the past. However it seems as though the quality of my monitor is such that I am defeated from posting "clean" images here because, as I say, I can't be confident that the effect will show up here if my monitor doesn't show the effect when my PC is playing direct from DVD (but does, very clearly, when viewing those photos I've taken).

As we are now clearly going round in circles, not helped by my PC hardware at not proving this effect, I think we'll never get an answer as to what is causing this effect that has been noticed by some others, so this may have to remain a curiosity.

 
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Re: EMI 2001 camera query - dark green tint on BBC shows?

Post by Refugee » Sun May 08, 2016 2:03 pm

It looks to me like noise being picked up by the decoder with very little getting into the reds.

 
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Re: EMI 2001 camera query - dark green tint on BBC shows?

Post by AidanLunn » Sun May 08, 2016 2:47 pm

But this happens on several TV sets I've tried, and only on BBC shows made using these cameras in the late 70. No other cameras, no ITV shows, and as other people have noticed it (Pye625 and it's mentioned on Martin Kempton's website linked above), so I strongly doubt it's anything to do with my equipment. I only took the photos because my computer monitor unexpectedly wouldn't show the issue, but any TV set I've tried does.

 
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Re: EMI 2001 camera query - dark green tint on BBC shows?

Post by occiput » Sun May 08, 2016 8:46 pm

I believe it was Prof R V Jones who explained Occam's Razor (the usual spelling) as follows:

'When I open the lecture theatre door and look into the corridor, I see many things but I would be very surprised to observe a tiger. The simplest explanation for this, and therefore the most likely, is that there is no tiger there. If I were to say that there is a tiger there when the door is closed, but he is frightened of me and hides when I open the door, you might well think me very peculiar indeed.'

You, I regret, are guilty of claiming that the tiger is frightened of you. Furthermore, you commit the error which graduates are supposed to have learned not to commit, of only attaching weight to material which supports your theory and disregarding that which doesn't. This is utterly fatal to the career of any aspirant in the engineering profession. If you want an example, drawn from one of the other disciplines, of where this ultimately leads, you might care to google "Sir Thomas Bouch" and "Tay Bridge".

There is no BBC modification to the EMI 2001 camera which is capable of producing the effect you describe. The biggest hint you have been given, but completely ignored, is that one of the programmes you claim to have seen the effect on was not made using 2001s at all.

I doubt I would be allowed to get away with the word I really want to use, so I will say that even if we dignify your ramblings with the label "theory", if they were an object they would bounce, and Leicester City would play with them.

There is another aphorism which seems relevant: 'when you are in a hole, stop digging'.

 
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Re: EMI 2001 camera query - dark green tint on BBC shows?

Post by sideband » Sun May 08, 2016 10:34 pm

As there seems to be a danger of this thread becoming unpleasant, I'm closing it before it gets out of hand.


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