Solution for Indirect Sunlight? 
Posted: 07 November 2009 04:52 PM   [ Ignore ]
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I know i cannot place the table under direct sunlight, but i will have a table located under some overhead lights or near a window with indirect sunlight

Is there any solution for DSI or LLP or any other technology that would help or solve the a overhead light or sun light being picked up by the IR Camera and messing up my blob detection?

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Posted: 07 November 2009 05:34 PM   [ Ignore ]   [ # 1 ]
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I am showing my table in a university foyer next week that is surrounded with glass walls.  I am going to try and do it using shadow detection and using the sunlight as the illumination source.  It seems to work fairly well, there are a few issues surrounding the blur filter of CCV making the shadows cast around the edges of the screen getting picked up by blobs though. I guess i will have a better idea next week how well this works.

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Posted: 07 November 2009 07:13 PM   [ Ignore ]   [ # 2 ]
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thanks, but i need a solution which can be taken to multiple venues, in your situation it sounds like your making use of the sun to detect blobs which is smart but doesnt work for me

thanks

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Posted: 08 November 2009 01:57 AM   [ Ignore ]   [ # 3 ]
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I can’t really give any direct experience, but i’ve known people who have FTIR tables saying that it can cope with sunlight (indirect via windows), they have a lot of LEDs one every 1 or 2cm, and a good quality bandpass filter.

My FTIR table only has 20 LEDs (whereas other people with tables a similar size have 180!) and only works in the dark, I can’t promise how well more LEDs would work in sunlight, but hopefully someone with more experience can come in and offer advice.

The other solution might be to run CCV in invert mode during sunlight, and then run it in normal mode in the dark?

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Posted: 08 November 2009 05:39 AM   [ Ignore ]   [ # 4 ]
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I posted this a while back - http://nuigroup.com/forums/viewthread/5240/

It was regarding IR lasers but someone else said it improved their blob tracking in daylight.

Unfortunately the images seem to have disappeared? I doubt I’ve still got them but will have a look - they must have been hosted somewhere....

p.s. Looks like the hosting site is down so they may appear later on.

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Posted: 08 November 2009 06:09 PM   [ Ignore ]   [ # 5 ]
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I think that you can use IR blocking foil for windows.

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Posted: 08 November 2009 07:19 PM   [ Ignore ]   [ # 6 ]
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Well i dont want to have to put foil on the windows, is there anything i can place inside the box to take care of this?

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Posted: 09 November 2009 05:16 AM   [ Ignore ]   [ # 7 ]
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I think, what zelo was referring to was for you to place IR blocking film on the surface of your table thereby blocking the IR that is outside the table from entering the table. Get a sample from your closest commercial glass wholesaler/reseller and give it a try. Also, I have recently see a nice comparison done by lagerkoller http://nuigroup.com/forums/viewthread/7634/

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Posted: 09 November 2009 05:53 AM   [ Ignore ]   [ # 8 ]
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JSnow - 09 November 2009 05:16 AM

I think, what zelo was referring to was for you to place IR blocking film on the surface of your table thereby blocking the IR that is outside the table from entering the table. Get a sample from your closest commercial glass wholesaler/reseller and give it a try. Also, I have recently see a nice comparison done by lagerkoller http://nuigroup.com/forums/viewthread/7634/

Note that this would only work with an FTIR setup: DI relies on the IR passing through the surface, and with LLP the source of IR is above the surface so it too must pass through.

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Posted: 09 November 2009 08:00 AM   [ Ignore ]   [ # 9 ]
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does anyone know if it’s posible to get a IR foil with spesific bandwith?

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Posted: 09 November 2009 01:45 PM   [ Ignore ]   [ # 10 ]
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So what about DSI??

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