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| Manfred Korn |
 Posted: Sun Mar 19, 2006 9:28 am |
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Guest
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Hello,
I've heard that CCD sensors are protected by IR filters, which should
reduce blurring of the images caused by stray light components that are
not in focus but could be detected by a uncovered CCD.
Is it possible to remove that IR filter get some improved nightsight
capability? Has anybody experience in that procedure?
Thanks in advance.
Manfred |
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| Chris Kuether |
| Posted: Mon Mar 20, 2006 7:29 pm |
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Guest
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Manfred Korn wrote:
[quote:9c1c74ee6d]Hello,
I've heard that CCD sensors are protected by IR filters, which should
reduce blurring of the images caused by stray light components that are
not in focus but could be detected by a uncovered CCD.
Is it possible to remove that IR filter get some improved nightsight
capability? Has anybody experience in that procedure?
Thanks in advance.
Manfred
We routinely do this on all our CCD cameras, there is a shift of focus[/quote:9c1c74ee6d]
because of the loss of optic thickness.
chris |
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| redbelly |
| Posted: Mon Mar 20, 2006 8:44 pm |
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Guest
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Manfred Korn wrote:
[quote:41bc537cc8]Hello,
I've heard that CCD sensors are protected by IR filters, which should
reduce blurring of the images caused by stray light components that are
not in focus but could be detected by a uncovered CCD.
Is it possible to remove that IR filter get some improved nightsight
capability? Has anybody experience in that procedure?
Thanks in advance.
Manfred
[/quote:41bc537cc8]
Many people seem to have removed IR-block filters from digital cameras,
according to this site:
http://www.jr-worldwi.de/photo/index.html?modding.html
Don't know about improved night vision; silicon CCD's are only
sensitive up to 1100 nm. IIRC, thermal imagers (for night vision) are
usually at 3000-4000 nm and longer wavelengths.
If you do this, it is recommended to replace the filter with a piece of
glass of (nearly) equal thickness, to keep the focus in the same plane.
Regards,
Mark |
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| Helpful person |
| Posted: Mon Mar 20, 2006 9:45 pm |
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Joined: 22 Jun 2004
Posts: 830
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Manfred Korn wrote:
[quote:fec2293e2c]Hello,
I've heard that CCD sensors are protected by IR filters, which should
reduce blurring of the images caused by stray light components that are
not in focus but could be detected by a uncovered CCD.
[/quote:fec2293e2c]
The IR filter is used to keep the color correct. With it removed the
IR light will show up as extra energy in the red channel.
[quote:fec2293e2c]
Is it possible to remove that IR filter get some improved nightsight
capability? Has anybody experience in that procedure?
[/quote:fec2293e2c]
You will not get improved night vision. What you will get is the
capability to illuminate with an IR LED.
(In addition, at night, image contrast is generally enhanced by using a
waveband longer than 650nm. Hence by removing the filter and using
just the red channel, contrast can be improved. Of course this assumes
that you still have enough light as this is usually done in an
intensified system.)
[quote:fec2293e2c]
Thanks in advance.
[/quote:fec2293e2c]
Plaese visit my web site at www.richardfisher.com
[quote:fec2293e2c]
Manfred[/quote:fec2293e2c] |
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