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ArcticMyst Security by Avery

Approximating laser power without LPM - A scientific way

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Jul 14, 2013
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well i mean i guess i could be selling Chinese lasers, or i could have bought one realized i got a Chinese laser, and want to return it or have them ship me the proper power module to replace.

What is sufficient proof?

I figured fighting fire with fire (false advertising vs. false proof) would be okay. And it really isn't false proof seeing as even at +/- 50mW (for the worst errors in calculations and readings i could have made) from the low 40s i got would be no where near the 200mW advertised to me.

ill tag some images of the laser i purchased then :p
Edit: Images not working so heres a link to my photo stream:
http://www.flickr.com/photos/98564860@N02/

Also just to make sure, i don't need to change the focus of the laser from infinity to anything else when its being measured correct?
 
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ARG

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Also just to make sure, i don't need to change the focus of the laser from infinity to anything else when its being measured correct?

As long as the whole beam is on the sensor you'll be fine :beer:
 
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I figured fighting fire with fire (false advertising vs. false proof) would be okay. And it really isn't false proof seeing as even at +/- 50mW (for the worst errors in calculations and readings i could have made) from the low 40s i got would be no where near the 200mW advertised to me.

This is false advertising. Any advertising or claims that are not 100% accurate are considered false advertising

Web definitions: False advertising or deceptive advertising is the use of false or misleading statements in advertising. As advertising has the potential to persuade people into commercial transactions that they might otherwise avoid, many governments around the world use regulations to control false, deceptive or misleading advertising. False advertising, in the most blatant of contexts, is illegal in most countries. However, advertisers still find ways to deceive consumers in ways that are legal, or technically illegal but unenforceable.

By asking us to send a LPM photo to help you trick the seller, you are asking us to break the law. You are breaking the law as well so I advise you to just be straight with the seller and see what happens, or send your laser to be metered and thus provide the TRUTH!

Also just to make sure, i don't need to change the focus of the laser from infinity to anything else when its being measured correct?

You are not using an approved measurement method so we cant comment on your method. If you were using a LPM then you would need to make sure the beam was perfectly centered on the sensor.
 
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norbyx

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Since you are new and haven't even filled in your location I sure cant help you with a false reading but I would be willing to test your laser if you ship it to me. I know there are many members with LPM that would do the same, depending on your location, my suggestion is that you find a trusted member, ship him the laser, make him do a nice LPM reading with graph and pictures and then decide if you want to make the claim to the seller.
No one here will provide you with a false reading, that is why we trust eachother in this comunity, we don't make false statements:
 
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ill offer to do the reading with my new Delta- Rubicon, you'll get the satisfaction of an accurate reading and know that your laser was one of the first to be tested on the Rubicon :D
 
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The logic seems right i give it a go although i really want a real LPM soon
 
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Oh boy, I never thought my thread would generate so much 'heat' literally.
I am in India, so there is no LPM nearby to compare.
However, coming to calorimeters, before the age of the semiconductor, calorimeter was pretty much anything anyone had. In the 19th century scientists got fairly accurate measurements. Heck, our thermodynamic unit system is based on this.

I understand the skeptism. And I like the skeptism. However, I think we all have a "scientific mindset here".
So whats wrong with experiment? Will it do any harm?
Why not experiment with water, copper, aluminum and then plug in the formula with specific heat.

Lets see how much deviation from LPM do we get!

Calling out tonyt! Please do the experiment. Take 5-6 readings and see what do you get?
 




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