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532nm 1W pointer is released now

rhd

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Actually if you're pointing the beam at night it can become very important. since your away from the radiation source It like how I the ehought to i use red lasers to my advantage when astrophtographing. Mesoscopic vision probably plays one of the roles in why each person sees 405 so werid. I see the beam better than a 660nm but that's due to amtospheric scattering. Yet the variation is so great amoung people.

The type of vision engaged depends on the intensity of the light you're viewing, not the time of day, or the darkness of your surroundings.

At least, that's my understanding... I've never bought the argument that the low light vision curve applies to bright beams viewed at night simply because the surroundings are dark. I've never seen any cited authority for that position.
 





joeyss

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The type of vision engaged depends on the intensity of the light you're viewing, not the time of day, or the darkness of your surroundings.

At least, that's my understanding... I've never bought the argument that the low light vision curve applies to bright beams viewed at night simply because the surroundings are dark. I've never seen any cited authority for that position.

Well I can tell you a 660nm laser appears much brighter after adjust to to the dark and defocus it and then use it as a sky pointing laser even if its only 50mw. I really depends on way you're using laser for. I 'd bet it depends on the ability of the coherent light to strip away darkness vision molecules. But if i close my eyes and light up a cyan green peak GID flashlight with a 405nm laser it looks much brighter after i've been in the dark for 30 mins. then i did the whole day in a light room. after turn the lights out its not as bright even with a 25 watt and 35 watt 6500k CFL in my room.
 
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Scotopic vision is black and white. If you're seeing the color of the beam then you're not in night vision mode ;)

As a side note, I often see 405nm low power beams (<100mW) in scotopic mode. They appear much brighter and grey instead of purple.

IMHO what applies to most of our beam viewing is mesopic vision, but there are no curves for that.
 
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joeyss

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Scotopic vision is black and white. If you're seeing the color of the beam then you're not in night vision mode ;)

As a side note, I often see 405nm low power beams (<100mW) in scotopic mode. They appear much brighter and grey instead of purple.

IMHO what applies to most of our beam viewing is mesopic vision, but there are no curves for that.

Yeah but if you're shining out side or have a low powered 473/445 in a dark room I think it helps out. I noticed laser beams seem much bright outside at night after awhile then they do in a room even against a black surface,

I know i sorted tested this out in a way I let my eyes adapt to darkness then charged up 2 glow in the dark flashlights with my 405nm laser and I closed my eyes while doing so. ( the old 2 cell style every read glowones.) they peak around cyan green. They were atleast 2x as bright even when compapred to them being full charged when i shut the light off. I could easily see my way around the room and they were annoying to have next to my bed.

I aways see 405 as purple your air might have stuff in it. my 50mw has a purple beam
 
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Try with a 30mW, that's the easiest of my lasers to see in scotopic mode. But yeah, the air here is as polluted as it gets :/
 
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Actually if you're pointing the beam at night it can become very important. since your away from the radiation source It like how I the ehought to i use red lasers to my advantage when astrophtographing. Mesoscopic vision probably plays one of the roles in why each person sees 405 so werid. I see the beam better than a 660nm but that's due to amtospheric scattering. Yet the variation is so great amoung people.

No it doesn't. The fact that you're seeing the color at all means you're not using scotopic vision. Scotopic vision is dominated by rods, not cones. Rods do not perceive color, only luminosity. Furthermore, scotopic vision does not even extend into 660nm. That's why people use red lights when looking at astronomical charts -- to not affect their scotopic vision.

One reason you're seeing the beam "better" is because your cones are not saturated from other light. It also looks different because of the contrast between dark and light.

Well I can tell you a 660nm laser appears much brighter after adjust to to the dark and defocus it and then use it as a sky pointing laser even if its only 50mw. I really depends on way you're using laser for. I 'd bet it depends on the ability of the coherent light to strip away darkness vision molecules. But if i close my eyes and light up a cyan green peak GID flashlight with a 405nm laser it looks much brighter after i've been in the dark for 30 mins. then i did the whole day in a light room. after turn the lights out its not as bright even with a 25 watt and 35 watt 6500k CFL in my room.

You're conflating two entirely different things. This is not scotopic vision affecting your ability to see colored light; this is you saturating and desaturating your cones well within the photopic range, except maybe with the 405nm laser after long durations. The 660nm is definitely relying on photopic vision via your cones, as will be the scattered light from any green.

Back to the 1W green laser: it is still entirely meaningless to talk about the lumens emitted by a 1W green laser with respect to scotopic vision unless you're measuring luminance which also requires the area over which the light is cast. You're only going to remain in the scotopic regime if your light levels are so low that you can't even perceive the color of the green laser. In that case, what is even the point of a 1W laser, in the typical sense, when the beam is so dispersed? Otherwise, you're still in the photopic regime -- which includes backscatter.
 
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wow damn 1w of 532 i can only imagine how damn bright that must be, a little too much haha.
 
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wow damn 1w of 532 i can only imagine how damn bright that must be, a little too much haha.

On a clear dark night its bright but not as much as I thought they would be once I finally got one. I haven't had a foggy night yet to break it out. I am guessing its going to be insanely bright then. I know my 400mW in the fog is pretty impressive my 900mW 532 should really be something to behold. Pics to come. C'mon fog!!!!!
 




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