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ArcticMyst Security by Avery

A lonely 638 beamshot

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So because of my basement flooding, the whole basement has to be rebuilt. Luckily insurance is paying for professionals to do all the rebuilding. The problem with the whole thing is my bedroom is in the basement, and since the workers need the rooms to be empty, and so their brilliant solution instead of simply moving my personal belongings upstairs was to PACK EVERYTHING UP AND PUT IT INTO STORAGE FOR 2 F@@@ING WEEKS.

Needless to say I'm pissed. I have little faith that any of my small items like the pile of micro SD cards on my shelf will be found. Also concern about people just tossing my SF501B into a box with no lens cap :(

But enough about that. My camera was lucky enough to survive the purge and I got the 638 nm ebay pen I ordered in the mail today.

slTlGd4l.jpg


Just one lonely beamshot taken in my now empty room. No fog or anything. But I wanted to share the lovely slighty-orangish-red color of 638 nm

EDIT: Here's a link to the full resolution: http://i.imgur.com/slTlGd4.jpg

EDIT2: Its been brought to my attention that this picture is misleading by showing the beam. Please note that in order to achieve this "beam" I used a long exposure
 
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Tmack

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I didn't think they made 638 in a pen. I thought only 650. Hmm. And the red pens are usually very overspec. Hmmm. Wonder what you've got there.
 
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Ill call 100% BS on that link and seller. Trust me, bought one before xmas to see the 638nm color compared to 650nm. Wanted to see it prior to builing my groove to ensure 638nm was the one I wanted. The thing is THE BIGGEST PIECE OF SHAT EVER! I swear it doesnt even have a diode in it, its a freakin LED! Im going to pull it apart now just to show how crappy it is!

DOT cant even be seen at 100 yards, never mind a beam! I have not once seen a beam out of this POS!

Proof of purchase-

 
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Well IDK what to tell you because I ordered from that seller and mine works fine. Definitely a laser diode in it because its a nice dot that I can see from 100 meters. I can't see the beam though even in the dark, which is normal of low powered red lasers. The beam in the photo is from a 15 second exposure an a decent amount of ambient dust from construction work.

Its definitely not 650 theres a slight but noticeable orange hue to the dot. It could be a bit over-spec but my method of testing by holding it against my skin yields no results.
 

Tmack

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Red is hard to get to sting. Even at high power that wavelength really doesn't heat your skin. I have a 250mw 650 and it will light a cig, but takes a very long time for me to even feel it on my skin.


The red pens I have all have that square diode in them . But my red pens are the $1-$3 ones from Tmart, and the dollar store lol. Not a traditional diode, but a diode,
 
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You might want to put a disclaimer on your photos then. Time exposure trickery and not saying it but claiming no fog or anything is kinda a cheap move IMO, its VERY misleading
 
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OP, does the laser dot have "wings" on it? (A thin line that extends either side of the dot) my 650 does and I'm lead to believe this is normal for 650 pens, but that a 635 wouldn't do it.
 
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red doesn't sting our skin as easily as other wavelengths because red light, 630nm-660nm, and maybe some beyond this range, passes through our flesh to a vastly greater degree than other light. thats why your flesh will glow orange-red with a red laser or white light passing through it. with white light, only the red is making it through, which is why I believe the glow still looks red orange and not white. too bad green light doesn't pass througth too, it'd be kinda cool to glow green.

It's true both single mode and multi mode 650 diodes I've seen have wings, but I'm not sure about single mode 638. could be a single mode 638 if indeed no wings, but I wouldnt be suprised if the diode is one not common around here due to it's low power. I mean, red lasers have pretty much been around the longest, one would think there would be more types of red diodes than other wavelengths
 

DJNY

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red doesn't sting our skin as easily as other wavelengths because red light

That´s just the case for the Aryan race :evil:

It depends on your skin color. I´m white-skinned, only got one (single-mode) 660nm laser in my LPF-history that is able to sting me (>> review soon :D)
 
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No wings. Just a clean dot.

I wish I had my 650 pen then I could take a picture of both of them next to each other for comparison.
 
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Thanks DJNY, it does help to be white. sorry darker people, all lasers like to burn you. damn rascist lasers!!!
 
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Tmack

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Haha. Yeah my skin heats up quicker than my girls. She if very fair, so when she's doing dished I have to hold it very still on the small of her back to get a scream.
 





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