Post by Deleted on May 31, 2014 23:43:00 GMT
Hi from Tasmania,
Back in 2000, I had a request from the university to design & build a series of computer controlled all sky cameras for climatology research.
This I did and one of the biggest problems was of course optical domes, glass preferably. The upshot after a lot of searching was to import acrylic domes direct from China in lots of 10 or more.
The firms I contacted were often happy to send a sample at low cost. Two things I found over time about acrylic domes was how quickly they deteriorated under the harsh Australian sunlight (UV attacks acrylic), the second was how atmospheric hydrocarbons also crazed the domes- vehicle exhaust fumes-especially diesel. Not an issue in the clean air of Tasmania as my own domes are still good after two years. This was a problem in the countries where I exported my systems to, Bangkok for example with its high density traffic & air pollution.
Sony did sell spare 90mm domes for their security cameras but I could only buy these through a trade supplier and they were not cheap but excellent quality.
Eventually I found a manufacturer who made the domes (with flanges) and gave them some sort of electronically deposited invisible coating which made them very resistant to both problems.
It is worth doing a search (in China) for acrylic domes with UV coatings, there are now many suppliers.
Glass domes are also available but more expensive.
Obviously my All Sky Camera's are commercial products so it is sensitive to give away my 'secrets' but I have given you the clues you need to know about domes. Those used on dummy CCTV cameras work also but I do not know how long they last when facing upwards.
picasaweb.google.com/109921669020426367250/SkyCam?authuser=0&feat=directlink
Regards & Clear Skies,
Shevill
Back in 2000, I had a request from the university to design & build a series of computer controlled all sky cameras for climatology research.
This I did and one of the biggest problems was of course optical domes, glass preferably. The upshot after a lot of searching was to import acrylic domes direct from China in lots of 10 or more.
The firms I contacted were often happy to send a sample at low cost. Two things I found over time about acrylic domes was how quickly they deteriorated under the harsh Australian sunlight (UV attacks acrylic), the second was how atmospheric hydrocarbons also crazed the domes- vehicle exhaust fumes-especially diesel. Not an issue in the clean air of Tasmania as my own domes are still good after two years. This was a problem in the countries where I exported my systems to, Bangkok for example with its high density traffic & air pollution.
Sony did sell spare 90mm domes for their security cameras but I could only buy these through a trade supplier and they were not cheap but excellent quality.
Eventually I found a manufacturer who made the domes (with flanges) and gave them some sort of electronically deposited invisible coating which made them very resistant to both problems.
It is worth doing a search (in China) for acrylic domes with UV coatings, there are now many suppliers.
Glass domes are also available but more expensive.
Obviously my All Sky Camera's are commercial products so it is sensitive to give away my 'secrets' but I have given you the clues you need to know about domes. Those used on dummy CCTV cameras work also but I do not know how long they last when facing upwards.
picasaweb.google.com/109921669020426367250/SkyCam?authuser=0&feat=directlink
Regards & Clear Skies,
Shevill