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Banned on April 7, 2007 Registered Member #277
Joined: Fri Mar 03 2006, 10:15AM
Location: Florida
Posts: 157
I'm seeking to purchase a "CoronaCam" (a type of night vision cam) so I can visually document suspected corona discharge on a powerline suspended 130 feet in the air. I've Googled and Ebayed, but so far have only found brief references or posts from other people who are also seeking to buy a CoronaCam, but no source for the CoronaCam. Any solid information as to a source would be much appreciated. Thanks. CM
Banned on April 7, 2007 Registered Member #277
Joined: Fri Mar 03 2006, 10:15AM
Location: Florida
Posts: 157
Bjorn:
Thanks! I emailed the company asking for a price quote. On the likely chance the quote comes back requiring that I take a 2nd mortgage on my home to buy it, I wonder as an alternative if a good quality night-vision videocam or scope might work to visually detect corona on a powerline? Comments anyone? CM
Registered Member #15
Joined: Thu Feb 02 2006, 01:11PM
Location:
Posts: 3068
CM,
I'm pretty sure you will be shocked to see how much these units go for. Better start thinking about that second mortgage. In fact, we do quite a bit of corona testing on high voltage equipment here at Lockheed Martin and we also found it to be prohibitedly expensive - too much to justify actually purchasing one. For our testing, we simply use a digital SLR camera and long exposure photography. This works extremely well. I would recommend this method for your experiments, however you will be limited to nightime photography. You'll also need a good long focal length lens.
Also, note that the glass in camera lenses attenuates the spectrum of light that corona is mostly made up of, so you'll need a pretty considerable source to actually show up on the sensor.
Registered Member #27
Joined: Fri Feb 03 2006, 02:20AM
Location: Hyperborea
Posts: 2058
Some times you can find special lenses like the Nikon UV ones on ebay or other places at an affordable price, Combined with a DSLR with the filters removed it could be quite efficient.
Banned on April 7, 2007 Registered Member #277
Joined: Fri Mar 03 2006, 10:15AM
Location: Florida
Posts: 157
Thanks guys, will look into it. Dan, I have sent 6 PMs to you since beginning of March concerning a previous HV matter from this board, all unread so far. Pls check them out. CM
Registered Member #30
Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706
As far as I know, the CoronaCam is a combination of an ordinary visible light video camera, a special UV video camera, and digital signal processing to combine the two pictures. It's not cheap :-o What makes it expensive is the UV video camera with its optics, and the intellectual property in the DSP unit.
Registered Member #311
Joined: Sun Mar 12 2006, 08:28PM
Location:
Posts: 253
I wonder how hard it would be to make a slow-scan UV camera using laser printer optics (spinning multi-facet mirror) and UV sensitive photodiode/photomultiplier...
Banned on April 7, 2007 Registered Member #277
Joined: Fri Mar 03 2006, 10:15AM
Location: Florida
Posts: 157
Dan:
To help me avoid expensive mistakes purchasing incorrect equipment, you mind saying what SLR camera make/model you use? and also the make/model ID for the lens?
BTW, received the quote for a CoronaCam.... $80,000 !
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Seeking to purchase CoronaCam
