EDIT 2016/3/6: verified the pwm frequency, which is 17.2 kHz on all modes except moonlight (8.6 kHz) and turbo (no pwm).
Astrolux S41 is a quad emitter hotrod light manufactured by Manker. It is equipped with either high CRI Nichia 219b or cool white Cree XP-G2 LEDs. My light is the Nichia variant purchased from banggood.com. The light is also available as a Manker E14.
Manufacturer specifications
- Battery type: 1x 18350, 16340 or 18650 with an optional tube
- LED: 4x Nichia 219B 5000 K (also available with 4x CREE XP-G2 6500 K)
- Body material: Aluminum/Copper
- Switch type: Reverse tailcap clicky
- Waterproof: Yes, IPX8
- Lens: TIR
- Protection: Low voltage warning (2.9-3.1 V), reverse polarity
- Modes: Selectable 4 or 7
- Special modes: 10 Hz strobe, battery check, biking flasher
- Mode memory: Selectable
- Length: 80 mm
- Width: 24 mm
- Weight: 90 g
The S41 driver is the same as in the popular BLF A6/Astrolux S1.
Astrolux S41 with a 18650 and a 18350 battery.
The light accepts protected and unprotected cells. In addition to 18350s 18650s can be used with an option 18650 tube. There’s a double spring in the tailcap.
Measurements
Please note: lumen measurements are only rough estimates
My diy 30 cm integrating styrofoam sphere has been calibrated using a Fenix E05 on high with manufacturer’s claim of 85 lumens. Verified with an Olight S10 that has been measured with a Labsphere FS2 integrating sphere by valostore.fi. Results may be more inaccurate with especially throwy or floody lights.
For spectral information and CRI calculations I have an X-rite i1Pro spectrophotometer with HCFR for the plot and ArgyllCMS spotread.exe for the data. For runtime tests I use spotread.exe with a custom script and a i1Display Pro because it doesn’t require calibration every 30 minutes like the i1Pro.
Explanation of abbreviations
CCT = correlated color temperature, higher temperature means cooler (bluish)
CRI (Ra) = color rendering index consisting of 8 different colors (R1-R8), max value 100
CRI (R9) = color rendering index with deep red, usually difficult for led based light sources, max value 100
TLCI = television lighting consistency index, max value 100
CQS (Qa) = Proposed replacement for CRI, RMS average of 15 color samples
CRI2012 (Ra,2012) = Another proposed replacement for CRI, consists of 17 color samples
MCRI = Color rendering index based on the memory of colors or 9 familiar objects
x,y = coordinates on a CIE 1931 chart
After 35 seconds on turbo with a 18650 battery, my lights drops down to moonlight and doesn’t recover before switching it back off and on again. The backward mode cycling with a long press also stops working after overheating.
*Spectral distribution
*
Color rendering
Beam and tint
Tint in different brightness modes is consistent. Mode 1 = moonlight, Mode 7 = Turbo.
Runtime
High 2 and Turbo
Medium 2 and High 1
