Probably because there is a norm (IS0 3664:2009) in the graphic & art industry. “The standard dictates that when viewing prints, a light source that replicates the D50 light source should be used”.
My board? What for? With any COBs you can just plug and solder the lead. The idea of COB is you don’t need any MCPCB to mount the LED. Those tiny LEDs already internally pre-wired, soldered ready to use.
Many printings used Philips Master TL-D 90 Graphica 965 before led took the market. Do not know much about the norms,but D65 is also a standart I guess.
I would love to upgrade the 5 meters of LED strip above my desk to high CRI. I only paid $2.42 for this 5 meter strip.
But I calculate 5 meters of your SunLike LED strip would cost $392.70. Did I calculate that correctly? Is that price assembled?
there is no 0.05w or 0.1w sunlike leds in this world, so, there is no led strip… I could not find any pcb like I need, so, I drawed it by myself. It is not led strip, it is pcb what need heat sink. Also you can use only 2S (2pcs) leds in one board, it will about 12v, but be carefull, use resistor.
Also the same 12w will cost 17$ from me (20 leds and 10pcb boards 99mm long) or 14.5$ if if will be 22mm pcbs.
22mm can be used in flashlights because there is not high voltage (36v) like in COB sunlike. For growing I use another leds. But if someone already use sunlike bulbs where it is possible, he can use sunlike for plants. Eyes first, plants after =) Will go to sleep, sorry.
I drawed this 99x12.5mm for alluminium profile for led lamp 60sm, but also it can be in another size. It will be about 30-36w led lamp 60sm long.
One suggestion, it's much better practice to connect LEDs in series first, and connect those series strings in parallel.
Reason for this is LEDs Vf variance, if you connect multiple LEDs in parallel, current distribution could be unequal, LED with lowest Vf will draw highest current, and because of that if will become hotter, and Vf would drop even more, current would rise even more.. etc. I've seen this problem in LED T8 tube light, shadows and bright spots were visible because of unequal current distribution and measurements confirmed that.
With 3 (or more) LEDs connected in series first, all strings would have total Vf closer to average (more leds - more equal average total Vf among strings because of probability laws).
1. seoul semico recommended to use their 3030 leds to 150mA, I recomend to use it on 85mA and I will use it with 0.5w
2. quality of leds is really good and it is almost with the same voltage.
3. when 1 led will die (shit happens) when those series strings in parallel, string will not work. If here, for example, 1 of 4 pcs will die, another 3pcs will work only 1.333 times more than 4pcs
4. in my situation it is possible to use it 3S4P and 2S4P and 1S8P
I changed price to 3030 leds on my web-site to 0.5$ and power too (now it is 0.5w, was 0.6w)
But seoul semico say that it is 150mA and 200mA max current. It is not good power to this leds, because the size of crystal not 1w. I mean it will die really fast with 150mA.
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