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# Laser Brightness calculator made by nprlaser :D

#### Nprlaser

##### Active member
Ever wanted to see EXACTLY how much brighter your 500mW 635nm is than your 2W blue? Here's my first official program that will measure and compare laser brightness through a list of common wavelengths and then adding power.
I got these number and value's from the 1988 C.I.E. Photopic Luminous Efficiency Function here 1988 CIE Photopic Luminous Efficiency Function.

All I did was using some information to get exact brightness factor for each wavelength. Building this program was actually more fun than I expected :yh:

Version 1.1 Beta January 25, 2014

+Fixed bugs

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Don't worry about the windows detecting bullcrap, this was made using visual studio.
Pictures

I just noticed a bug with the 520nm and 515nm Efficiency Factor,
520=.71
515=.6082
to get these readings manually use this equation
EF*mW*0.683002=lumens

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#### XxCodyDarnellxX

##### New member
I don't particularly need a calculator, as I have a good idea of each laser's respective brightness, but this does look like a well built and easy to use program for quick and accurate comparisons. Nice work. :beer:

+Rep

#### DJNY

##### Well-known member
rhd also did one back in 2011 Beam: (559nm 1mw) vs. (476nm 1mw)

I wonder how the accuracy of these two tools is in comparison

But with this your contribution to the forum is definitely worth a +rep !

#### Nprlaser

##### Active member
rhd also did one back in 2011 Beam: (559nm 1mw) vs. (476nm 1mw)

I wonder how the accuracy of these two tools is in comparison

But with this your contribution to the forum is definitely worth a +rep !

Oh wow, looks like some one else did make a similar tool, i never knew. The factor chart is slightly different than the one I used but his calculator is better, its actually what I wanted to do with the color bars and and a more fun look. But i didn't have the time to add all 300+ wavelengths, I just stuck with the common ones. Thanks

#### ZRaffleticket

##### Well-known member
I'm fairly certain you should calculate the wavelength color, 300+ constants is just a waste.

Still, cool tool! I'd like to see if it does get better eventually.

Edit: Ahh, I see how it works now. Calculating would be annoying. What language is it coded in?

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#### Nprlaser

##### Active member
I'm fairly certain you should calculate the wavelength color, 300+ constants is just a waste.

Still, cool tool! I'd like to see if it does get better eventually.

Edit: Ahh, I see how it works now. Calculating would be annoying. What language is it coded in?

I used visual basic, and unless I could find an equation that will save me from adding hundreds of numbers, it will have to stay with the drop down list. I'm adding improvements right now since I'm in study hall

#### ZRaffleticket

##### Well-known member
VB6?

You could just have the table saved as a csv and read from that for the wavelength EF.

As for color... Hm. So the limits you'd need to place are when a certain wavelength hits
255,0,0 (say 660nm)
<between>green rises and red drops
0,255,0 (say 530nm)
<between>blue rises and green drops
0,0,255 (say 450nm)

You'd need to set where certain color values start to drop (it won't be immediate).

I'd probably do something along those lines.

#### Laserface

##### New member
This is exactly what I've been looking for. Thank you so much for doing this!

#### hakzaw1

##### Well-known member
LIKE-- "wow I just got a red projector that is 200mW!! of 650nm
WHAT a rip off that other want that much for one with 640nm
at ONLY 100mW!!"
well guess what kids??- the 638 IS BRIGHTER the numers do not lie nor do the videos-
WHY do you think no savvy PJ builder uses ANY reds above 640nm??
AT the LSO course we were told that a 1WATT 445 is only as 'bright ' as a 50 mW 532?? yeaH... go wrap your head around that fact!!

not to mention that some seller have no interest in facts when it comes to the lasers or scanners they sell- one may call his scanners 15K while another sez the same ones he has are 30K -- AND they will tell you the laser output BEFORE losses- whioch is far from what can be metered after losses.
I measured the loss from a 300 mW green last night-- is was 230mw after just the dichro losses more gets lost at the scanner too.
so going by mw /dollar is a BIG noobish mistake

brb with a very telling video

if any of you can put these links into a post 'embedded' please do that for me- I never learned the trick...

norty303's Avatar norty303 norty303 is online now
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Default Re: can you help??

I shot them in my garage so can confirm the powers used.

Quote Originally Posted by hakzaw1
I thought I saw a post by you with links to a YTube vid showing 640 red next to 650??

Some pointy heads at LPF want to argue with me saying there is no big difference- I need to show them that vid as it speaks volumes-
just a link to your post or vids ..would be great.. thanks for putting that up- I was not all that surprized by it but many will be in shock--lol

Len In TEXAS

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#### hakzaw1

##### Well-known member
+5 to the OP - nice share to be sure..