Laser Spec Questions
Posted: 14 July 2008 11:19 AM   [ Ignore ]
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1. What wave length is the best to use for this style of setup? I have seen pretty much an even split between 780nm and 850nm. Is there a benefit to one over the other?

2. What should the average cost for a laser unit be? I have seen them range greatly between $10-$90. They all appear to have the same specs, but could I be missing something?

3. What is the exact name of the lens I should be searching for?

4. Where is everyone doing there shopping for the lasers, lenses, and other accessories for this setup?

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Posted: 14 July 2008 12:45 PM   [ Ignore ]   [ # 1 ]
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There should not be much of a difference between the 780 and the 850, though the 780 may have a slight red glow to it.  The cost really can be anything from 4 to 97 dollars.  The lens you are looking for is a Line Lens.  When a dot is shown into the lens it is scattered out as a solid line.  Most of us are using 120 Degree Line Lenses, I believe.  AlexP sells his custom made lasers, though they are pretty expensive.  Many of us have been getting our lasers as Aixiz.com.  They sell cheap ones.

Also, be sure to read AlexP’s article on Laser Safety.

Good Luck!

Alex

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Posted: 14 July 2008 12:50 PM   [ Ignore ]   [ # 2 ]
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1) As i only have 850nm lasers i can’t compare this.

2) Depends very much on where you buy them

3) Line line, which is atleast 89% so you can cover your complete window from the corners..

4) Well i bought first 2x 850nm 10mw lasers from AlexP here on the forums which have a 120% line lens, but i’m having some problems with the blobs. So i orderd 4x 780nm 25mw lasers from aixiz.com, they are very cheap, but i don’t know if they are reliable yet as they aren’t shipped :( . But i did only order them last thursday smile

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Posted: 14 July 2008 01:24 PM   [ Ignore ]   [ # 3 ]
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The only reason I asked about the wavelength is because I noticed AlexP started off with 780nm and moved to 850nm. I would assume power is going to be the key factor in coverage, but I was thinking that it may have something to do with visibility by the camera. Has anyone posted results or experiences with the lasers from aixiz.com?

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Posted: 14 July 2008 03:56 PM   [ Ignore ]   [ # 4 ]
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No, I don’t think anyone has recieved them yet, only placed orders.  Vlado should be getting his soon, I as well.  Both of us by the end of the week, I think.

Ill post some videos of my success(or failure) on my blog, which is linked in my sig.

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Posted: 14 July 2008 11:00 PM   [ Ignore ]   [ # 5 ]
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Yes please post the results of the 780nm testing! Be sure to have proper eye protection while doing so.

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