Delvance
Enlightened
Hello all,
I conducted a quick test of several of my lights tonight, and compared them to some values that were given by AWR's hotrater spreadsheet and just wanted to share some info regarding the common back of the envelope equations and ratios that most of us CPF'ers take for granted and use.
Ok the lights i used and some background info
My custom 3D ROP LE/large
A well running top shelf ROP is usually expected to output around 700 lumens or so.
This supeROP (with high bulb) is running on 4 18650s in 2S2P and as such, the cells don't sag much and manages to deliver more power to the bulb. The magswitch is completely fixed also. I have compared this ROP to a SF m4/6 and a 2D fixed switch CBP 1650 ROP and it just ate them. So naturally i would expect at least high 700 output lumens, but more around the 800 mark.
I have measured around 7.6V at the lamp with fresh cells and plugged this value into AWR's hotrater and it gives me a figure of 892 torch lumens.
2D ROP CBP160
A standard recipe ROP (with low bulb installed). Powered by 6 CBP1650s and sporting a completely fixed switch. The expected output of this configuration would be somewhere around 300-350 and certainly looks it as it compares favourable to an SF M4 with HOLA.
Seeing as the light is running 6 CBP1650s in it, the expected voltage would be around 7.2V. Plugging 7.2V into AWR's hotrater gives a figure of 338 torch lumens
G&P R500 Scorpion
A relatively new light that has become very famous over in the incan section of CPF. It is powered by two 18650 Li-Ions in series and puts out a gorgeous beam. The claimed output lumens by G&P is 500. Many members, upon purchasing this light, have compared it to their SF M6 and advise that the R500 is putting out around 85% of the light of an SF M6.
So now we have a very rough idea of torch lumens for each light.
I then measured the overall output of each light using a lightbox apparatus (built exactly like the one featured on FLR) and got the following numbers for each light
SupeROP - 550
2D ROP (low) - 207
G&P R500 - 257
Ok now some values/equations that CPF'ers take for granted...sometimes
So with these back of the envelope equations/ratios in mind, and reports by other CPF'ers, i would expect my
-SupeROP to give 892 torch lumens (straight from the Hotrater)
-2D ROP low to give around 300-350 torch lumens (from Hotrater and comparisons)
-R500 to give around 425 lumens (based on a member saying it was about 85% of an SF M6)
Now we look at the output figures obtained from the lightbox and times that number by 1.62 due to the lights being measured being incandescents.
SupeROP: 550*1.62 = 891 torch lumens
2D ROP low: 207*1.62 = 335 torch lumens
R500: 257*1.62 = 416 torch lumens
:wow: , the torch lumen obtained from the lightbox for the supeROP is ONE output lumen off what the hotrater gives!
But wait! The lightbox gave a torch lumen figure for the 2D ROP of 335 lumens...only THREE output lumens off the figure obtained from the hotrater.
And the R500 is indeed around 80-85% of an SF M6's output at around 416 torch lumens.
Now before i get flamed and receive massive lectures lol...i just want to say yup...i know very well that this is not a scientific test or anything and does not constitute as proof that the above formulas/ratios are correct. And that my logic contained here is very loose and makes for ALOT of assumptions...but that's all we have as most CPF'ers can't exactly afford an integrating sphere. It is something i've noticed over time and i thought i would just like to share this simple observation with CPF.
I conducted a quick test of several of my lights tonight, and compared them to some values that were given by AWR's hotrater spreadsheet and just wanted to share some info regarding the common back of the envelope equations and ratios that most of us CPF'ers take for granted and use.
Ok the lights i used and some background info
My custom 3D ROP LE/large
A well running top shelf ROP is usually expected to output around 700 lumens or so.
This supeROP (with high bulb) is running on 4 18650s in 2S2P and as such, the cells don't sag much and manages to deliver more power to the bulb. The magswitch is completely fixed also. I have compared this ROP to a SF m4/6 and a 2D fixed switch CBP 1650 ROP and it just ate them. So naturally i would expect at least high 700 output lumens, but more around the 800 mark.
I have measured around 7.6V at the lamp with fresh cells and plugged this value into AWR's hotrater and it gives me a figure of 892 torch lumens.
2D ROP CBP160
A standard recipe ROP (with low bulb installed). Powered by 6 CBP1650s and sporting a completely fixed switch. The expected output of this configuration would be somewhere around 300-350 and certainly looks it as it compares favourable to an SF M4 with HOLA.
Seeing as the light is running 6 CBP1650s in it, the expected voltage would be around 7.2V. Plugging 7.2V into AWR's hotrater gives a figure of 338 torch lumens
G&P R500 Scorpion
A relatively new light that has become very famous over in the incan section of CPF. It is powered by two 18650 Li-Ions in series and puts out a gorgeous beam. The claimed output lumens by G&P is 500. Many members, upon purchasing this light, have compared it to their SF M6 and advise that the R500 is putting out around 85% of the light of an SF M6.
So now we have a very rough idea of torch lumens for each light.
I then measured the overall output of each light using a lightbox apparatus (built exactly like the one featured on FLR) and got the following numbers for each light
SupeROP - 550
2D ROP (low) - 207
G&P R500 - 257
Ok now some values/equations that CPF'ers take for granted...sometimes
- 65% light transmission efficiency from bulb lumens to output/torch lumens
- Overdrive formula i.e. base lumens*(overdrive voltage at lamp/ bulb rated voltage)^3.5
- Lightbox apparatus ratio multiplier for output figure obtained from the lightbox are 1.39 for LEDs and 1.62 for incan lights. Using these multipliers has been known to give a rough estimate of the actual torch lumens. Looking through the numbers of various lights tested on FLR. I would tend to agree. Eg. HDS U60 on max gave an overall output number of 44.3. 44.3*1.39 = 61.6 output lumens. Sounds about right for a HDS U60. (sidenote: HDS lights are configured to output the model numbers lumens from the factory. Independent integrating sphere tests have shown HDS 60 lights do put out around 60 lumens +/- 3 or so).
So with these back of the envelope equations/ratios in mind, and reports by other CPF'ers, i would expect my
-SupeROP to give 892 torch lumens (straight from the Hotrater)
-2D ROP low to give around 300-350 torch lumens (from Hotrater and comparisons)
-R500 to give around 425 lumens (based on a member saying it was about 85% of an SF M6)
Now we look at the output figures obtained from the lightbox and times that number by 1.62 due to the lights being measured being incandescents.
SupeROP: 550*1.62 = 891 torch lumens
2D ROP low: 207*1.62 = 335 torch lumens
R500: 257*1.62 = 416 torch lumens
:wow: , the torch lumen obtained from the lightbox for the supeROP is ONE output lumen off what the hotrater gives!
But wait! The lightbox gave a torch lumen figure for the 2D ROP of 335 lumens...only THREE output lumens off the figure obtained from the hotrater.
And the R500 is indeed around 80-85% of an SF M6's output at around 416 torch lumens.
Now before i get flamed and receive massive lectures lol...i just want to say yup...i know very well that this is not a scientific test or anything and does not constitute as proof that the above formulas/ratios are correct. And that my logic contained here is very loose and makes for ALOT of assumptions...but that's all we have as most CPF'ers can't exactly afford an integrating sphere. It is something i've noticed over time and i thought i would just like to share this simple observation with CPF.
