User SunLike from sunlikelamp.com sent me their SunLike8 SMD SAW E27 LED bulb for testing.
Store page: SunLike∞
Options as tested
The main specs by the manufacturer:
–4200K color temperature (4000K + 5000K mix with 2:1 ratio)
-CRI (Ra) 98
-SunLike SMD 3030 SAW emitters
–8W power rating
-AC voltage of 220/230V (also available in 110/120V and 3-35V DC)
-Couple of options for reflector and lens instead of diffuser
Measurements
Measurements were made in a 50cm integrating sphere with an x-rite i1pro spectrometer after the bulbs had warmed up for 1 hour. Intensity (lux at 1 meter, candela) was measured outside the sphere at 50cm.
The bulbs were connected to mains power which at the time of testing was at 225V.
Power consumption at the time of measuring the CRI parameters was 7.8 watts at 225 volts with a low power factor of 0.59. Total bulb efficacy is ok for an ultra high CRI light source at 80 lumens per watt.
Output at 1 hour is 631 lumens. The output drops 8.5% during the first hour from 690 lumens at turn on. This is a sign of good heatsinking, which is also evident by just looking at the bulb.
Maximum output is reached immediately. Light output in lumens was plotted over one hour. Output is stable after the intial warmup.
Color rendering
The CRI data was measured integrated after a 1 hour warmup in an integrating sphere.
Color rendering is excellent at CRI Ra of 99 and R9 of 98. TM-30-18 fidelity index Rf of 98 and gamut index Rg of 101 are also excellent. There’s three distinct but small humps in the spectrum at different wavelengths (450, 520 and 620 nm). There’s no near UV content.
Visually the light is neutral white with excellent saturation to all the colors it illuminates.
Load IES TM-30-18 Color Rendition Report by clicking the thumbnail:
CGATS CRI Data file:
Color temperature and tint
Tint is right on the black body line. Remember that when LEDs heat up, their duv value almost always decreases and becomes less green/yellow. This was measured after 1 hour in an integrating sphere.
Tint is very even around the bulb thanks to the heavily diffused bulb.
Flicker
The switching frequency of of 33kHz is not visible to the eye. The snob index of 0% guarantees that it’s easy on the eyes. High frequency flicker is probably not visible to a camera at high shutter speed either.
AC power draw
Current is drawn in short pulses 100 times a second as the input voltage gets high. There’s no power factor correction which results in a power factor of 0.6.
Cyan line: mains line voltage
Yellow line: current draw of the bulb
Violet line: power draw (voltage * current)
Verdict
A neutral ultra high CRI bulb from SunLikeLamp is battling with the best of them. The Korean Seoul Semiconductor SAW SMD emitters produce a beautiful 4200K beam emulating sunlight very well. The light is flicker free and very stable in output thanks to the good heatsink and good driver.
Please note that the test was done when the bulb was brand new. I can’t guarantee that they will perform similarly after months or years of use.
