Rasilon
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Joined: Wed Mar 11, 2015 7:30 pm

why do I have purple pics

Sat May 11, 2019 9:01 pm

Image I am using an IR lamp and the cam is noir
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jamesh
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Re: why do I have purple pics

Sat May 11, 2019 9:09 pm

I would expect that sort of colour effect when using a noir camera in daylight even with an IR lamp.
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Rasilon
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Re: why do I have purple pics

Sat May 11, 2019 9:29 pm

ah ok, any suggestions on getting better daylight video/pics, Can I use another type of picam with IR lamp?

HermannSW
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Re: why do I have purple pics

Sun May 12, 2019 1:33 am

Daylight images with NoIR camera look strange:
https://forum.arduino.cc/index.php?PHPS ... msg3268945
Image


If you want nomal daylight images, use a "normal" camera with IR filter, or a camera where you can enable/disable IR filter:
Image
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Rasilon
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Re: why do I have purple pics

Sun May 12, 2019 6:06 am

I would like to be able to use the Cam at night with the seperate IR Lamp, and take normal video by day. What pi cam do I need for this.

jamesh
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Re: why do I have purple pics

Sun May 12, 2019 7:59 am

Rasilon wrote:
Sun May 12, 2019 6:06 am
I would like to be able to use the Cam at night with the seperate IR Lamp, and take normal video by day. What pi cam do I need for this.
That's normally done in commercial camera by having a activated filter moving out of the way for low light.
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HermannSW
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Re: why do I have purple pics

Sun May 12, 2019 8:30 am

jamesh wrote:
Sun May 12, 2019 7:59 am
moving out of the way for low light.
That typically requires a motor, here is a sample Raspberry (not official) camera (I have not tried):
http://www.arducam.com/arducam-noir-ras ... ut-filter/

Quite expensive, 35$/65$ for 5MP/8MP camera on uctronics.com (normal prices: v1 camera (clone) <8$, v2 camera 25$).
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Re: why do I have purple pics

Sun May 12, 2019 9:19 am

Rasilon wrote:
Sun May 12, 2019 6:06 am
I would like to be able to use the Cam at night with the seperate IR Lamp, and take normal video by day. What pi cam do I need for this.
Your problem is caused by the R, G & B pixels being sensitive to infrared as well as to their own colour (actually they're each sensitive to the full spectrum, but have a dye on their surface to reduce their sensitivity to the wrong wavelengths. That dye lets through IR, so a separate IR filter is placed over the sensor, and that's left off in the Noir camera.)

What you need is a camera with one of the green pixels in the Bayer pattern replaced by an Infrared-sensitive pixel - RGBI instead of RGBG
Either that, or have two separate cameras (which means two Pis - maybe run a Zero in Gadget mode?) and select the right one for the conditions.

Rasilon
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Re: why do I have purple pics

Sun May 12, 2019 7:06 pm

I think I have found what I need. Would someone look at it and advise me please. https://www.amazon.ca/Raspberry-Camera- ... way&sr=8-9

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Re: why do I have purple pics

Mon May 13, 2019 9:18 am

I have no experience with that camera, but it uses the same sensor as the Official camera (and also the camera you tried a couple of years ago) so it should work.

As you found out then (viewtopic.php?f=43&t=166352&p=1098583#p1099032) the 3v3 supply to the camera module is far too delicate to drive IR LEDs, but it may be enough to drive the filter motor.

Try it and see, and report back!

Rasilon
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Re: why do I have purple pics

Mon Jun 03, 2019 11:15 pm

Works brilliant. very nice video day or night.

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