Green vs. Violet Blue

[Kevinito]

I currently have a green laser which I bought from Think Geek and am currently looking at their violet blue version of laser. Would this violet blue (405) version do well as a star pointer (i.e. seeing the beam at night)?

Here are the specs since I cannot post a link (as of yet) . . .

# 405nm wavelength
# Output power of <5mW
# Continuous wave (not pulsed) output
# Takes two CR2, 3V batteries (not included)
# Class IIIa laser product

Thanks!

 

[ElektroFreak]

If you're needing a visible beam at night for astronomy purposes, stick with the green. Green is right at the peak of human eye sensitivity, so no other color is as visible.

 

[XCreedX]

Exactly blu-ray has florescence with it, still depends on how much it is, would be still cool to have.

 

[hydrogenman15]

If you're needing a visible beam at night for astronomy purposes, stick with the green. Green is right at the peak of human eye sensitivity, so no other color is as visible.

In the dark (were he will most likely be using it) the the most visible color is closer to 500nm. If you are in well lighted conditions then the most visible wavelength (If i remember this correctly) is closer to 555nm. I remember
seeing a chart that shows this...but I don't remember where I saw it. Although, 500nm lasers are still quite expensive and 500nm isn't incredibly much brighter than 532nm in the dark.

--hydro15

 

[rocketparrotlet]

ThinkGeek is a rip-off. Go to the Buy/Sell/Trade thread to check out our 405nm lasers for sale. You can get to about 200mW safely with a 6x diode.

-Mark

 

[Schrecken_Licht]

You could use a 405nm for star pointing, but you would need way more than 5mw... more like at least 100mw. Even so, a 5mw greenie will look brighter at night (whether it's hazy or not outdoors) than 100mw of 405nm. Also, usually you can't see the beam of a violet laser unless you are close to looking down the axis of the beam, rather like 660nm.

 

[iskor12]

ThinkGeek is a rip-off.  Go to the Buy/Sell/Trade thread to check out our 405nm lasers for sale.  You can get to about 200mW safely with a 6x diode.

-Mark

It is true, thinkgeek charges way to much for a laser pointer.  
Take this into consideration.
Thinkgeeks 5mW green laser costs $69.99
http://www.thinkgeek.com/gadgets/lights/5a47/
DX 5mW green laser costs $10.50
http://www.dealextreme.com/details.dx/sku.91

THinkgeek 5mW Violet laser $169.99
http://www.thinkgeek.com/gadgets/lights/b847/
[highlight]Make your own using a PHR diode
100mW violet laser ....less than $100 with a visible beam[/highlight]

Don't waist your money there

 

[Deleted member 8382]

first of all what others said, forget about thinkgeek absolutely.

If you have a minimum DIY skills, build it yourself.

If you don't want to build nothing, then the best option is this

http://www.o-like.com/b2b_cpinfo.asp?id=947

Yours,
Albert

 

[Switch]

blu-ray is just horrible for star pointing, the beam gets so blurry at long distances you can't even see it.