By the latest testing for the LED Bulbs: OSRAM, Philips, FSL, Media and Opple(FLS and Opple are Chinese local big brands), we get some interesting summary. (Reminding: we test these bulbs with Preheat 0second and preheat 3 mins, then compare these 2 sets data)
1. For all the brands, the actual lumin is much higher than the specification which is printed on the color box. For example: For OSRAM, it print 860LM on the box, actually it's > 940LM.For Philips, it prints 600LM, actually >700LM. For FLS, it prints 500LM, actually >580LM
2. After preheat 3 mins, for all the bulbs, the CCT increased 100~250k
3. After preheat 3 mins, for all the bulbs, both the Lumin efficiency and the overall output lumin reduced. Philips is the biggest reduction: about 9% overall lumin reduction. While OSRAM is the smallest reduction: about 4 %.
4. After preheat 3 mins, for all the bulbs, the Ra increased a little: from Ra82~Ra 85
5. After preheating 3 mins, for all the bulbs(except 1 pc of OSRAM), the input wattage reduced
6. We also test the SDCM, which is not shown in this reports. We find all the bulbs' SDCM reduced after 3 mins working
7. For all the bulbs, the actual CCT<Its specification which is printed on the color box.(well, only low brand make higher CCT let it looks more bright?)
We can see all the bulbs with around 100lm\w and Ra>80.Another question:
1.Is 100lm\w the popular standards now for LED bulbs?
2. Is Ra 80 the popular standards now for LED bulbs?
3. For FSL, its actual watt is only 5.88~6.13w(print 7w on the box). But its actual lumin is 20% higher than its printed specification. So: can we say it's ok or not ok? Reminding: most of the customers select bulbs by checking its watt, although finally, they need is lumin(but most of my friends who are not in Lighting industry, they totally have no idea for Lumin).
Another testing is going on, welcome your reading then.