User SunLike from sunlikelamp.com sent me a Remez E27 LED bulb for testing.
Store page: http://sunlikelamp.com/index.php?route=product/category&path=59_105
Manufacturer website: https://remezlight.com/en/production/light-for-home/led-bulbs/led-a60-7w-5700k/
The main specs by the manufacturer:
–5700K color temperature (also available in 3000K)
-CRI (Ra) 95
-SunLike SMD 3030 emitters
–455 lumens
–7W power rating (also available in a 9W version)
-Power factor >0.5
-AC voltage range of 170-260V (also available in 110/120V)
-Not dimmable
–30000 hour lifetime
–5 year warranty
The bulb is also available with an E14 candelabra base in 5 and 7 watts.
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 228V.
Output at 1 hour is 563 lumens. This is significantly brighter than the manufacturer’s spec of 455 lumens. The output drops 16% during the first hour from 667 lumens at turn on.
The bulb is very light so there’s not much heatsinking, which explains the long winded drop in output. Thankfully the power of the bulb is not very high either so it doesn’t get exceedingly hot. I don’t know if the higher power 9W version has the same configuration. In any case the manufacturer provides a 5 year warranty for the bulb.
Power consumption was measured at 6.8 watts at 238 volts with a low power factor of 0.6. Total bulb efficacy is ok for an ultra high CRI light source at 83 lumens per watt.
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 98 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 cool white with excellent saturation to all the colors it illuminates.
Load IES TM-30-18 Color Rendition Reports by clicking the thumbnails:
CGATS CRI Data file:
https://pastebin.com/YQAnduan
Color temperature and tint
Tint is very slightly above 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 A60 sized bulb.
Flicker
The switching frequency of of 56kHz 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
The cool white SunLike bulb from Remez offers neutral daylight and one of the best reproduction of colors from an LED light source. It has a reasonable 500 lumen light output and a very affordable price ($7 plus shipping). There’s no visible flicker to the eye or to a camera and the bulb turns on immediately at full power. The heatsinking could be better, but the 5 year warranty should cover any premature deaths.
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.
