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Blue laser for Astronomy?

samposs

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I recently ordered a 1W 445nm Blue laser and was wondering if that would be ok and effective to use for astronomy. I know that generally the green lasers are used for astronomy, but I enjoy the blue color a lot more and as im just now getting into astronomy im not sure if there is another benefit or reason to use green other than blue. I also figured that the higher power will make up for the brightness difference between the 445nm and the 520nm. Thanks in advance.
 

Sta

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445nm is not as good for astronomy because of the multimode nature of the diode. This means that it has a very rectangular beam. It is much easier to point at something with a round beam than a rectangular one. Also, there is greater risk to your eyes with 445nm, because of the high power.
 

samposs

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Thanks for the info, I think ill take your advice and buy a 100mw green one when I get a little more money to spare. I used to have one but I gave it to my grandfather after I saw how much he loved using it.
 
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CurtisOliver

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I have always wondered why they don't use a red laser instead. You rely on your eyes being adjusted to night vision to observe the stars. Red doesn't deter away from this, which is why astronomers often use red light to read there star maps. There are single mode 635's out there. But for ease of accessibility you can't go wrong with a green laser for brightness.
 

Eracoy

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I have to say that on the matter of eye safety, there is hardly a difference between a 100mW green and a whatever-watt blue. They will both zap your peepers pretty harshly without safety goggles.
 

Sta

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I have to say that on the matter of eye safety, there is hardly a difference between a 100mW green and a whatever-watt blue. They will both zap your peepers pretty harshly without safety goggles.
I have to disagree. A reflection from glass of a 100mW green is usually not dangerous, as most glass reflects 5-10% of light. However a 1W+ blue laser is still very dangerous when reflected from glass, as the reflected beam is at least 50-100mW.
 

Hap

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There are single mode 635's out there. But for ease of accessibility you can't go wrong with a green laser for brightness.
DragonLasers sells corrected 637nm Spartans at powers of 90mW's. Let me tell you, that is pretty bright and if shone across my house the dot is still a nice looking dot! If you are looking for a bright beam corrected multimode red this is probably the best option :yh:

-Alex
 

Sta

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DragonLasers sells corrected 637nm Spartans at powers of 90mW's. Let me tell you, that is pretty bright and if shone across my house the dot is still a nice looking dot! If you are looking for a bright beam corrected multimode red this is probably the best option :yh:

-Alex
Is the knurling on the 637nm spartan split like it is in the image, or all connected like it is with the 589? I'd get one but I want some way to distinguish between it and my 589.
 

Hap

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Is the knurling on the 637nm spartan split like it is in the image, or all connected like it is with the 589? I'd get one but I want some way to distinguish between it and my 589.
Hey Sta,

Nope, they look identical! The only difference is just looking into the aperture(while it's off of course!!!!!!! :eek:) and you'll see a difference :)

-Alex
 
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trencheel303

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I have always wondered why they don't use a red laser instead. You rely on your eyes being adjusted to night vision to observe the stars. Red doesn't deter away from this, which is why astronomers often use red light to read there star maps. There are single mode 635's out there. But for ease of accessibility you can't go wrong with a green laser for brightness.
Correct. Green and blue completely knackers your night vision. I discovered this when doing a star trails shoot out in the wilderness one day. I also took my lasers along and wondered why I couldn't see any stars afterwards. You really need to be past the 532 part of the spectrum and heading at least towards yellow to not ruin your night vision. I'd like to think my ~100mW 589 would work, but I've never tried it for star pointing.
 

Razako

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My 589nm spartan is amazing for star pointing. The beam is bright enough to see well, and yet doesn't destroy your night vision or attract a huge amount of attention.
 

trencheel303

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I thought it would be, but I didn't want to speculate. I'm gonna dig mine out tonight, it's been a while :beer:
 

CurtisOliver

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589 for star pointing. I like the sound of that :D Our own mini laser guide star. :whistle:
 




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