I want very even light on my desk so I was thinking about a large COB panel.
No hard set size but something like 3 or 4 feet long and 1 foot wide.
Preferably 240v
Output should be similar to a 200 W regular light bulb.
I’ve found plenty of COB lights on AE but they are all (very) small.
Do large COB panels exist?
If you want the equivalent of a 200 Watt regular light bulb, you’re looking for something that gives you 1,500 lumen. Maybe you should be thinking of making a “cabinet” with an opaque piece of glass to mount over your desk.
In the day, a standard incandescent 100 watt bulb was rated at ~1600 lumens. Right? So he would really need more like 3200 lumens… yes? That is a lot of COBB…
Yeah maybe a cabinet with a bunch of strings of LEDs and a good diffuser? AND good heat dissipation.
I got my info from THIS (Dutch) website. The four rows are (in that order) corresponding to:
the original tungsten bulb, a Xenon lightbulb, a fluorescent lightsource, and a led light.
So a led source is emitting only 10% heat compared to the old lightbulb.
With the size you mentioned, allow a bit of airflow, and you should not be worried about overheating.
CRI: Most are 80, 90 is rare, but found a few unique 97
Color: Some panels have an adjustable tint. Unfortunately all are UGR 22
I don’t really need color adjustable but because it’s hard for me to decide which one to buy it shurely is a bonus.
Unfortunately all those panels are UGR 22 and I’m not willing to go above 19, and because I’m a lot behind my screen everyday (work + hobby) I just want something good. Meaning deep down I want UGR 16.
For what I do on my computer (desk) high cri isn’t of utmost importance. My screens are great for office work (very crisp letters) but my guess is that those working in the art world will get a heart attack when they see my color settings.
But still my aim is high CRI. I just tend to think that when all things are optimal that undefinable feeling of quality.
So I guess my wishlist is:
UGR 16 or lower - Most imporant
CRI 90 or higher
Adjustable color - Least important
And of course the light should be even, because bright spots would spoil everything, even if all above mentioned ideals are met
I want bright light everywhere on mu desk. No shade or hotspots.
The desk is diy and will be between 3 and 4 feet long and about 3 feet deep.
(I want legroom and use 3x 43")
That forces me to buy large panels.
That said all panels seem to be designed to light up large rooms like school, office and shops. AE has small ones but they have almost no specs and look inferior.
So a panel with all the right specs, but half the lm would be fine. Because it likely gonna be vast overkill I’ll pick a dimmable panel.
You don’t want a cob panel, that’s silly, and probably why you’re having trouble finding something. You just want an integrated LED light fixture. You won’t see the individual LEDs, its the same effect as a cob.
A COB is one chip. They can only be so big. Im not sure one exists in that that size. But there’s no reason you need 10,000 diodes to be built into one single 4’x1’ chip, you can just use 200 diodes built into a single fixture behind a piece of frosted glass, lined up to mimic old fluorescent tubes.
COB would be like if you want a single small 12v light to imitate the flood from a light fixture. You have the room for an actual light fixture. You can just get one of those.
I don’t think it’s too much lumens btw. Depends how high you want to mount it over the bench of course. I’ve got several times that over a similarly sized bench. You could get almost 100,000 lumens out of a 4’x1’ fixture if you wanted to, and they do sell those. I’ve got some that are 24"x20", 450w, close to 100,000 lumens, and its thinner than a cell phone
I like floody flashlights. I’ve some mules. Tried zebralight headlamp, then the better Skillhunt. Then I bought a el-cheapo cob headlight that really impresses me. No hotspot like a mule light.
Anyway, I started this thread with COB, but found led panels, and they are as you say a bunch of seperate led. How things are done varies per brand or price. The more high-end ones seem to diffuse the light with a zillion tiny reflectors.
I’ve been thinking about frosted glass, but I wonder how that affects CRI?
How high over my bench?
At the moment I have only a plan and an empty room.
I’m considering something similar like those hanging cabinets over my desk. But then the lights would be located much closer to my line of sight then when I hang then on my ceiling.
Frosted glass shouldn’t affect CRI at all. I can’t see why it would. I have 98cri LED light bulbs and they’re all inside a translucent bulb. Though I guess it’s some kind of plastic, not actually glass. Frosted glass is probably the wrong term to use. You don’t really need anything at all if the LEDs are packed close enough together
Height you would just play around with. Mine are on rope ratchet light hangers, you can lift it up and down
You might be better off mounting lights on the ceiling or simply using a chandelier with decent LED bulbs. There are some fairly inexpensive bar lights that can be ceiling mounted and run off a 12V DC converter operating on 240 V AC. I use some of these in my garage and as supplemental lighting in a bedroom. I actually have 10 of the bare strips on the way from China and they cost me $16 for 10 without any housing. You can see what a strip looks like here 1-10pcs*50cm DC12V SMD 5730 LED Hard Rigid LED Strip Bar Light Aluminium shell | eBay Each strip has 36 LEDs. is 50 cm long, and for natural white, my favorite hue, puts out 1260 lumens. Just hang as many as you need for the intensity you want. You can use an inexpensive dimmer installed between the power source and the strip if desired.