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phred

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  1. phred

    How does bright light hurt a CCD?

    Good idea regards
  2. phred

    What's wrong with this picture?

    Good man ---- You're hired Attaching the camera housing in that way will ensure it becomes part of the same Faraday Cage so all voltages will rise and fall at the same time, just as the experts at www.lightning.org recommend. Also see this post by Rooney http://www.cctvforum.com/post-49997.html&highlight=#49997 who lives in an area where lightning is an issue. .
  3. phred

    How does bright light hurt a CCD?

    Excess light alone should not cause overheating by the mechanism you describe ie 'overvolting' CCDs have a very sharp cutoff in response beyond which additional light will not increase the output. The excess light will however cause additional heating as visible light is absorbed by many materials and becomes IR (quantum mechanics). It is actually pretty difficult to get rid of all IR without cooling the CCD. There are many different designs of CCD and some can tolerate more heat than others. Those with microlenses and filters made of plastics, for example, are more easily damaged by overexposure. The problem with using your video cameras is that they have not been designed for 24/7 use and the CCDs will not be designed with longterm overexposure in mind. I also suspect they may suffer from image burn as a result of viewing the same scene for long periods. (good questions btw )
  4. phred

    What's wrong with this picture?

    CSG your post sums you up perfectly.
  5. phred

    What's wrong with this picture?

    Ok jisaacmagee, my misunderstanding. Lightning is not something I would bother about here either. Doing a proper protection job is quite involved and at the end of the day you can still end up with toast. My objection was to the pseudo science nonsense and false claims about lightning protection and 'building zap' by CSG – I think the guy has been reading too many Marvel comics. In an area where lightning strikes are a real threat his suggestion would actually make matters worse. Regards
  6. phred

    Auto-iris lens

    Very possible you have a damaged CCD. Sometimes the tiny wire connections give up. Effects of this can vary from complete failure to false colour rendering.
  7. phred

    How does bright light hurt a CCD?

    If you have ever used a magnifying glass to focus the sun on a piece of paper you will understand the problem. The damage to the CCD is usually caused by excessive heat build up as the lens focuses the sun on the CCD. I have tested some CCDs to destruction in a lab setup, usually they just stop working but just a few have exploded You really should do all you can to avoid pointing your camera at the sun. Reflected sunlight and car headlights are less of a worry - they just tend to ruin the image. Smearing is... as Kensplace says.. Google 'CCD smearing' you should find some examples.
  8. phred

    What's wrong with this picture?

    Thank you for the reassurance - I know from past experience that what you say is true. I was however, referring to licenses for security installers. Perhaps a more likely explanation is that CSG is not who or what he claims to be.
  9. phred

    What's wrong with this picture?

    Only a good earth bond will give you protection from lightning. Plastic insulators are useless at very high voltage – the only thing that comes close are those huge glazed ceramic isolators you see on overhead power cables or the Soapstone blocks used at the bottom of high power transmitter antenna - they still need special grounding in case of lightning strikes.
  10. CCD technology has been pushed so far into low light territory for things like thermal imaging, I can't see CMOS catching up for several years, if at all. Cmos does have advantages in almost every other respect now - like 250 times the contrast ratio and twice the bit depth. What I would like to see is more cameras that have both types of imager cmos for day and CCD for night.
  11. phred

    What's wrong with this picture?

    OK, you got me, that was a wind up just to get me on my soapbox
  12. phred

    What's wrong with this picture?

    no ground - apart from the cable http://www.lightning.org/?page=faq
  13. phred

    What's wrong with this picture?

    Two of the safest places to be in an electrical storm Inside a metal clad building or a motor vehicle. The metalwork acts as an efficient conductor allowing the energy to discharge to ground. Attempting to isolate a camera from a metal building is a waste of time. There is no insulator that will hold back 100,000,000 volts. Even if you could do it you would then create a situation where, if lightning struck the camera, the path of least resistance would now be the cable from the camera. Not a good idea to put 100,000,000 volts into a DVR. There is nothing you can do that will 100% protect sensitive outdoor equipment from the effects of lightning – the best you can do is provide an efficient earth conductor. Suggesting that a plywood sheet is protection from lightning is simply nonsense. By all means use it to stabilise the camera but please, drop the pseudo science crap. CSG calls himself a professional licensed installer, I can only assume that they hand licenses out in New York in exchange for a couple of cereal packet tops.
  14. I was thinking more of the 'corporate culture'. HP used to be similar years ago while IBM were a bunch or arrogant ***** For such a large company Kodak are pretty far down the lawsuit table compared with Microsoft and Intel. Surprising when they hold over 1000 patents on camera technology alone. As for the Sony case they obviously agreed that Kodak had a valid point as they eventually paid up and signed a licensing agreement without going to court- same agreement was already in place with Sanyo and Olympus. Kodak also accepted some of Sony's technology as part payment. Courts also found in favor of Kodak in the Sun Java case. The same technology has been licensed to many, including Microsoft, for many years so why should Sun get it for free - Sun were effectively charging their own clients for technology belonging to Kodak. Many of Intel's lawsuits against Via failed despite their huge legal budget. Just thinking about it, I have lost count of the number of lawsuits Intel filed against Via and I don't remember too many succeeding.
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