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ArcticMyst Security by Avery

515nm vs 561nm

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Feb 17, 2008
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Lucky.. I had to get a module. I wonder if my module was just taken from one of these pens or was already a separate item. It's interesting because my module is almost double the 5mw output these pens were meant to have.

I know :D

I don't think it's extracted from a pen. I believe the module inside my GLP is capable of more but the power supply from CR2 is limiting it. Mine is rated at 4.4mW.
 





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Ah I see, just like pulse width modulation on some of my cheaper flashlights. Usually more expensive flashlights use a linear driver so they don't have that annoying PWM :( but on lasers it prolly isn't annoying at all :D

You should check out a pulsed flashlight driver in a dark room with a camera on it, it's interesting that you can see the scan lines go across the screen as it tries to keep up with the light. Good think our eyes don't work exactly as cameras do with a view screen, or we'd be seeing the same thing! Also very interesting if you program a micro controller to pulse an LED at different speeds, going down to 1 millisecond per pulse and the view screen looks like a screen door with only one of the directions. I did an experiment on this quite some time ago with a camera, maybe I'll be able to find some pictures - if I do I'll post them.
 

Razako

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Honestly I love the pulsed operation on my 561nm. Shining it around outside at night on objects you get a strobed tracer effect.
 
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One more

HqRRbMM.jpg
 
D

Deleted member 16589

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Wow I just tried my 515 and 561nm And am playing with the raw in Photoshop. I cant even get close. Best i can get for the 515 is using tungsten white balance setting but then the 561 looks lime green.
 
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Wow I just tried my 515 and 561nm And am playing with the raw in Photoshop. I cant even get close. Best i can get for the 515 is using tungsten white balance setting but then the 561 looks lime green.

For the last shot I had to adjust the WB a little bit in lightroom. I use shade setting for WB. Also try to keep the f stop as low as possible. I tried high f stop and both of them ended being the same color.
 
D

Deleted member 16589

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For the last shot I had to adjust the WB a little bit in lightroom. I use shade setting for WB. Also try to keep the f stop as low as possible. I tried high f stop and both of them ended being the same color.

Yea I'm just using a Sony SLT a65 with the kit lens so low light is my enemy. Other than horrible noise the best result I got was ISO 6400 at a higher shutter speed. The sensor probably has just as much if not more to do with it than the camera or settings.
 
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Trevor

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Wow I just tried my 515 and 561nm And am playing with the raw in Photoshop. I cant even get close. Best i can get for the 515 is using tungsten white balance setting but then the 561 looks lime green.

For the last shot I had to adjust the WB a little bit in lightroom. I use shade setting for WB. Also try to keep the f stop as low as possible. I tried high f stop and both of them ended being the same color.

Yea I'm just using a Sony SLT a65 with the kit lens so low light is my enemy. Other than horrible noise the best result I got was ISO 6400 at a higher shutter speed. The sensor probably has just as much if not more to do with it than the camera or settings.

Simple explanation: This has everything to do with the Bayer filter that is on your camera's sensor. That Bayer filter lets your camera see color... by throwing away 2/3 of the light that enters your camera lens.

Wikipedia: https://en.wikipedia.org/wiki/Bayer_filter

In short, how much of a particular wavelength (515, 532, and 561 for instance) gets through each component of your camera's Bayer filter will affect how the wavelength is represented.

That's the reason a lot of cameras show 405nm as blue - it only gets through to the blue pixels, and the camera can't represent it appropriately as violet.

Trevor
 
D

Deleted member 16589

Guest
Simple explanation: This has everything to do with the Bayer filter that is on your camera's sensor. That Bayer filter lets your camera see color... by throwing away 2/3 of the light that enters your camera lens.

Wikipedia: https://en.wikipedia.org/wiki/Bayer_filter

In short, how much of a particular wavelength (515, 532, and 561 for instance) gets through each component of your camera's Bayer filter will affect how the wavelength is represented.

That's the reason a lot of cameras show 405nm as blue - it only gets through to the blue pixels, and the camera can't represent it appropriately as violet.

Trevor

It looks like we need a CYGM camera
https://en.wikipedia.org/wiki/CYGM_filter
 
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You should check out a pulsed flashlight driver in a dark room with a camera on it, it's interesting that you can see the scan lines go across the screen as it tries to keep up with the light. Good think our eyes don't work exactly as cameras do with a view screen, or we'd be seeing the same thing! Also very interesting if you program a micro controller to pulse an LED at different speeds, going down to 1 millisecond per pulse and the view screen looks like a screen door with only one of the directions. I did an experiment on this quite some time ago with a camera, maybe I'll be able to find some pictures - if I do I'll post them.

Haha yeah I use to do that all the time with my old Streamlight PT2L, that flashlight had the worst case of pwm I've ever seen lol! Yeah if you do end up doing that again I'd love to see it.
 




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