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Keith Walters

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Everything posted by Keith Walters

  1. Has anybody else noticed that while Mr. Guedes' English is appalling sometimes to the point of incomprehensibility, his spelling is always perfect? Are you using the Babelfish Translator by any chance, Mr Guedes?
  2. quote name='Jim Jannard' post='126576' date='Sep 11 2006, 10:44 PM'] It is not necessary for us to show you our breadbox to convince you the footage is real. Jim I think you mean "Breadboard" and no, it's not necessary for you to put it on display to convince some, or I daresay, most of the posters here. However, if you did put on some sort of actual hardware display it would go a long way toward removing any lingering doubts. I still don't understand why you're reluctant to show us even a photo of it. I mean, to play the Devil's Advocate, when you get right down to it we really have nothing but your word that the images came from your prototype, and not say, a D-20 you hired for a couple of days. In another post you challenged us to explain why you would put pixel dropouts and other defects into a computer-generated image. No disrespect, but I'd have to say that is EXACTLY what I would do if I was trying to pull such a scam! Not that I'm suggesting you are, but that is how less generous-spirited people might think.
  3. But why do you think we wouldn't? This is not a autopsy of a 3-month-dead murder victim we're talking about here, just a collection of electronic parts. After all, you are dealing with an industry that lives and dies on the makeshift, on the "she'll-be-right-if-it's not-in-shot" philosophy, the industry that invented gaffer tape, dulling spray and people standing round holding bits of cardboard to flag off highlights. What you have probably looks little different to what we've seen on the sets of a dozen mad scientist flicks. I presume it mostly works on 5 Volts, 12 at the most, so there is no electrical hazard. Or is the problem that you can't actually show realtime live images yet? If that's the issue I don't know why it would such a big deal, after all you don't get to see movie film straight away either.
  4. Those devices really only comment on the health or otherwise of the signals being received, and to a large part can be built using the same components as the communication links they are designed to test. It's another thing altogether to process real time high definition video, particularly at the resolution stated. In any event, the purpose of my original post was to clarify what sounded like an outrageous claim, which as it happened, RED deny actually making. So, as has so often been the case here and on other forums, it was either somebody's overactive imagination running away with him, or more likely somebody who simply had no idea what he was talking about.
  5. Is it possible that RED are looking at other potential markets such as surveillance? I can think of a number of government agencies that would have lots of uses for a cheap 4K reasonably portable CCTV camera. They more than anyone would be interested in 300mm lenses.
  6. What do you mean by "handling" though? 5GB/S is just the rate the raw data comes in, actual real-time video processing at that data rate would be a prodigious task, particularly for something that has to be portable and able to run off batteries. Getting the software bugs out of something that runs that fast would also be a major challenge. It's an interesting point that at present there doesn't appear to be a single manufacturer of HD digital set top boxes who has managed to get his software working reliably! Consider that they are receivers only, working with a much lower data rate, and the size of that market... As far as video camera technology goes, I have been involved in several projects over the past 20 years that required sometimes major redesign of commercial CCD cameras. Initially these were automated surveillance applications. A side effect of all this was that I had to put in a lot of in-depth study on exactly how CCD (and CMOS) sensors operate, what their limitations are and so on, as we struggled to get the last ounce of performance out of them. Later when I worked for Panavision Australia I put this to good use designing video tap cameras, among other things. For a while I was also responsible for the maintenance of their Betacam fleet, although they got out of that in the early 90s. Like other technically literate people, when somebody from a small firm with no track record in the field announces that they've suddenly made a major and long-desired technological breakthrough that has thus far defeated the combined intellectual muscle of the likes of Sony, Kodak, Philips and all the other "usual suspects", my first reaction is to ask: "That's nice. But HOW did you do it?" I'm not saying he can't possibly do it, all I (and quite a few others here) are really asking is HOW is he doing it. I have no doubt Mr Jannard has the resources to do lots of things, he just seems remarkably reluctant to tell us what they are, in anything but the vaguest terms at any rate. In any event, he'd cerainly need to do more than to "drive home with the best hyper high-speed ADC engineer in the world," he'd also need a place for him to put his designs into actual hardware. It's not just a matter of the actual design, in general he would also need a way to fabricate higher-performance chips than are currently available. If his engineer failed to deliver the goods, he could just terminate his employment, but you can't get a refund on a state-of-the-art wafer fab facility quite so easily. In any event, I doubt that even HE could afford to build one of those. I have no doubt he is going to produce some sort of camera, although how he is going to achieve this at the price quoted remains the major mystery. It all depends on what he actually means by "66dB". (I made a mistake in my calculation by the way. 60dB is about a million times power gain, another 6dB is another four times giving 4 million total, the square root of that is about 2,000 as you say, just short of 2,048 which represents 2^11 or 11 stops. For some reason I decided 6dB represents a doubling of power, not voltage!) Unfortunately "latitude" is something of a weasel word. With film, the exposure latitude is somewhat arbitrary, because even when you get past the quoted figure, there is still information being recorded on the emulsion, which could be extracted by advanced film scanning technologies such as the "double exposure" system of the Arriscan. The main point here is that there really is no point where the emulsion "stops working", it's more a matter of what level of distortion is considered acceptable. Any "mile high" pinpoints of the image tend to get "rounded-off" rather than "sliced-off" which is visually much more acceptable. With an electronic sensor, once past the quoted exposure latitude, there is usually nothing recorded but a white blob, and no amount of post-processing now or in the future will ever recover anything from those areas.
  7. "or is that "bullandgoose"?" I'm sorry, I've got no idea what that means. "Nice to see you post your real name this time. " Obviously you have me confused with somebody else. I've only ever made a small number of posts here and they've always been under this name. I used to have an older account under a made-up name, but I've long since forgotten what the signin name was and I hadn't posted anything for years, just been a "lurker". When they started the crackdown on user names earlier this month it was easier to start afresh. Until recently you couldn't open an account with a "freebie" e-mail address either , but that appears to have changed. "And I acknowledge receipt of your personal email." I don't remember sending one to you. (Unfortunately my mailbox didn't save copies of what I have sent) Well anyway, 66dB means a sensor output voltage range of about 1,400 to 1 or about 11 bits. Somewhat more realistic, and not all that different to what you get from current model HDTV cameras. I must confess I'm a trifle concerned about some of the extravagant claims I've been hearing on other forums. Every time I hear reports of "noiseless" images I have to ask does that mean "Images without any noise" or "Images where the noise has been removed". When are you going to post some stills either on your site or somewhere we can access them?
  8. From the information that is now appearing on similar forums to this one and other places on the Net, RED are claiming that their "Mysterium" sensor has a 14-15 f-stop dynamic range. Can somebody tell me exactly what that means? If a "stop" means a doubling of the incoming photon intensity in the normal photographic sense, are they saying that the difference in brightness between the most dimly illuminated and the most brightly illuminated pixels of a captured scene can be as much as 2^15 (two raised to the 15th power) ie 32,768 times? In other words, (assuming one could actually MAKE a lens this good) for every one photon striking the darkest pixel, there could be around 32 thousand photons striking the brightest pixel! Or do they mean something else? Let's just put that into perspective for a moment. Everything you watch on TV (either broadcast or from DVD etc) at some point is going to be processed and/or delivered with/as an 8-bit luminance signal. That means that the maximum possible number of brightness steps between the darkest and brighest pixels on the screen is 256. (A lot of Plasma and LCD TV manufacturers claim some remarkable dynamic range figures eg 10,000:1 for their products, but that just means you can vary the size of those 255 "steps", over a considerable range, really an attempt to give you the same range of overall brightness and contrast that you used to get with a regular CRT-based TV). It doesn't mean that that there are 10,000 possible brightness increments in the on-screen image! If you think of the smallest possible brightness step as 1 centimetre, which is about as thick as the end of your little finger, then an 2.4 Metre (8-foot) household ceiling (which is the minimum allowed under most building codes) is pretty close to 256 little-finger widths. So if the tip of your little finger represents one bit, the minimum brightness increment, then the floor to ceiling height approximately represents an 8 bit luminance signal, which is all you are ever going to see broadcast to your TV set. Yet nobody is going to claim that 8 bits isn't enough. You see some stunning images on prime-time TV, which have been rather convincingly squeezed through that 8-bit bottleneck! So the trick is obviously to capture and compress the extremes of brightness that occur in the real world and massage them through that tiny transmission "hole". In a TV studio they normally go to a great deal of trouble to ensure that the lighting never exceeds an 8-stop range but you can do that because you're normally completely cut off from the extremes of the outside world. And how big are these extremes? Well using our building analogy, if you regard 8 bits as being the same as 8 stops, then if we have a camera with a 10-bit dynamic range, with the same iris setting as an 8-bit camera it should be able to handle a dark to bright difference of four times 256 = 1024. 1024 cm is about 32 feet - (which is about the height of a three-story block of units, the biggest you can normally build without providing an elevator). Without touching the iris or otherwise altering the exposure, you should then be able to take the camera back into the 8-stop-lit studio an capture images there, without them becoming excessively noisy. Of course, for transmission the images can't remain the way they were captured, the 10-bit images will need to be adjusted down to the normal 8 bits, but the important think that is often overlooked is that the camera has to capture the dynamic range before it can process it! What about 15 stops? Well that's 32 feet x 2^15 (32) = 1,024 feet! Which is a just little bit shorter than the empire state building! If you consider the very maximum exposure that film emulsion can produce anything recognisable from as being 20 stops (sunlight reflecting of wet leaves or similar) well that would be 2 ^ 20 times, a little bit over a million. A million centimetres is 10,000 kilometres - about six miles - or the height of Mt Everest! But getting back to the Empire State Building claimed by RED, this sure raises some interesting questions. Unless they use some sort of analog pre-processing a 15-stop dynamic range mandates the use of a 15-bit analog-to-digital converter. But according to their figures, if it's a 5K sensor it must have around 14 million pixels. At 24 fps that equates to 336 million 15-bit samples per second. While you can get 8-bit ADCs that work at that speed, I've never heard of any 15-bit units that go anywhere near that fast. (A 15-bit ADC is 128 times the size and complexity of an 8-bit unit). The Arri D-20 sensor is divided up into 32 separate channels, each with its own (I think) 12-bit ADC. So I'd love to know where RED are getting their chips made, and also what sort of signal processing technology they have than can process over 5 Gigabits per second? And why Jim Jannard only seems interested in applying all these technological breakthroughs to a cheap movie camera. It's all quite fascinating, and I look forward to seeing the results of all this in due course.
  9. If it wasn't for "that s**t" either NTSC would have had only 240 visible scanning lines, (288 for PAL) OR you would have only been able to have three or (absolutely maximum) four TV channels in each city, OR you could have had 480 visible lines but at only 30 frames per second, which would have flickered intolerably. (288 at 25 fps for PAL which would have even worse to look at). If you went for the second option, the 12MHz or more channel bandwidth also needed would have required much more expensive antenna systems both at the transmitter and in the home, and home videotape would probably never have become affordable if it ever became practical at all. If you ever get hold of one of the television engineering handbooks written by Fink and others in the 1930s, you'll see that an enormous amount of thought went into the original NTSC TV standard, which also formed the basis of the CCIR standard used in Europe and elsewhere. Basically, the 525 line interlaced scan system they laid down in 1941 was the highest performance broadcast system that was considered practical either then, or in the forseeable future. It's taken 50 years to come up with anything that's both affordable and significantly better, so they obviously knew what they were doing.
  10. When DVD movies first began to proliferate, I kept seeing references to a brand-new species of editing professional, the "compressionist". This was supposed to be a technician whose job was to run through the uncompressed master tape and flag any picture content likely to generate compression artifacts. After that (presumably in conjunction with with other types of editor) any offending footage would then be "doctored" or even deleted altogether to minimise or remove the problem. However this idea certainly seems to have fallen by the wayside. Or maybe it was just something that somebody thought might happen, and was turned into "fact" by the media. :lol:
  11. With the greatest respect Jim, I didn't think THOSE pictures were all that "Super" and I'm certainly not the only one. (I'm not saying they were TERRIBLE, but I would have expected more form a project with a budget that size.) However if you could get pictures of that quality from something that costs under US$20K, well that would be an entirely different story, and I don't think too many people would disagree with that. Can we ask what sort of images you shot for your recent 4K screening, and how they were stored? And why can't you show us a picture of your breadboard? Most people know what a prototype looks like, nobody is going to laugh at you.
  12. You know, around 15 years ago when digital video processing was just starting to gain momentum, I predicted there would come a time when all the hundreds of individual electronic parts that make up a Betacam or similar would be replaced with software-based processing using just a couple of LSI chips, and the tape-based VTRs would be replaced with Hard Disc units. Engineering types accepted that notion readily enough, but what they wouldn't accept was that with that change, the manufacturing advantage would shift to the US and Europe with their much greater strength in software design. One startling consequence would be that the video camera market could well become dominated by non-Japanese manufacturers whom nobody had ever heard of. And so it now appears to be the case with High definition video cameras! Although the RED is principally being designed as cinematography camera, with its proposed price, I'm sure it will see plenty of action as a studio HDTV camera. Can it be done for the price quoted? Well, everybody thought that DVD players would always be based on Japanese technologies, but just about all of them now are based on the same Zoran Chipset, designed in California. Those all-in-one chips are the reason we can buy a fully-functional full-featured DVD player for less than A$40 (around US$28). They've barely been on the market for a decade, and who would have believed in that time the player price would be dropping close to the price of a movie disc! It's hard to believe that it was ten years ago that I first started to see samples of miniature colour surveillance cameras that basically consisted of a tiny circuit board with a CCD chip on one side and a single digital processing chip on the other. I can't see any reason why this can't be scaled up to 4K resolution, and once that is achieved, the HD video market will be changed beyond recognition, the same way the still camera market has. I wish I had the money to embark on a project like this, but I'd probably prefer to be remembered for something more mundane, like a range of TVs, DVD recorders etc that anyone over 40 can operate without needing a degree in electronics and linguistics!
  13. A link like this: NanoLab would be nice :D Now that you've raised the subject, I've got a Super-8 camera with about 10 feet left of a 50 foot roll of Ektachrome that I bought about five years ago. The camera has been stored in a cool dark place all this time so will the images still be viable? Also, the price included processing, but I can't remember what the procedure is, and the photo place I bought it from has closed down. Will Kodak still accept it? And another question, does your range include super-8 negative film? (I'm not really familiar with film type numbers) I've always wanted to do something with Super-8 since I found a box of 30-year-old (some nearly 40 years old!) home movies when cleaning out a garage. I bought a projector for $4 in a flea market which I got going with some rubber belts intended as VCR spare parts, and the films seem to project as well as the day they were taken! Considering how hot that garage gets in the summer, I thought it was incredible that they survived at all.
  14. Yesterday my wife persuaded me to go to the movies. She seems to get a sort of "Cabin Fever" thing every now and again where it seems she suddenly just HAS to get out and see something, nearly always when there's nothing but crap on. I'm the first to admit I'm totally un-patriotic as far as films are concerned. I think the vast majority of home-grown Aussie films are rubbish, and I rarely watch them, even when they finally come to TV. BUT she'd heard that there was an Australian film called "Kenny" which some of her friends thought was hilarious, and a reviewer in a local paper gave it 9 out of 10 (which is always a worry for me, what are they going to give a film that really IS good!) What was is it about? No idea, she said. Oh great...... So we fronted up and I bought our "half-price-tuesday" tickets, a huge bucket of popcorn and two giant cokes and we found our way into cinema #7, to see there were all of four other people in there (two of whom walked out halfway through)<_< Then when the film started the first thing I noticed was the unmistakeable edge artifacts of 576p video painfully obvious on the big screen, followed by massive "outside-world burnout" on scenes shot in the cabin of a truck. Jeezus Christ..... But DESPITE all that, the film was hilarious, and I soon stopped noticing all the technical deficiencies. Basically it's a pseudo-documentary about a guy called Kenny, who works for a company that supplies portable toilet facilities for sporting events and the like. It's a total gross-out almost from start to finish, although I only realized later that nowhere do we actually get to SEE any of the, er stuff that Kenny has to deal with. The highlight of the film was probably when, as a reward for his hard work, his company sends Kenny to a "Pumpers Convention" in Nashville Tennessee, and it's filmed at a real convention, where they actually DO have all the latest and greatest of portable sanitation equipment on display. Anyway, in the credits they mentioned "MiniDV to HD conversion" although they don't mention whether the whole thing was shot on MiniDV. I've been trying to find out how it was shot, but there's not a lot about it on the internet. But it just goes to show that you can produce worthwhile cinema-release images with quite low-cost equipment, if the story is suited to the format. The documentary style of Kenny looks OK with the rough and ready video format, although there was a really noticeable lack of background detail (even my wife noticed this). This is the sort of "cult" film that can do well at film festivals, and the themes are pretty universal. If it gets released in your country, make an effort to see it, it really is a quirky masterpiece.
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