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A big thing not often spoken about with eye strain is dry eye caused by the lack of blinking due to focusing on screens too close to our face. This is an evolutionary phenomenon--close dangers cause extreme focus without blinking. Extreme focus on close items reduces our blinks. Our eye lids have glands in them that release oils on your eye with each blink. These oils help prevent the watery part of your tears from e…
> An even, diffused lighting environment is best for the eyes indeed. i am unsure where the love for those "spotlights" embedded into the ceiling comes from. every time i enter a room that has them i want to crouch like gollum. the only thing they seem to do is blind you. indirect lights can be expensive and hard to find though. i built 12 hanging lamps that illuminate the ceiling instead of the floor myself, which s…
The office-style solution is big diffuse ceiling lights. The easy but rather inefficient solution is indirect lighting. The expensive solution is to use high-end architectural lights that have a trim or lens design that makes the light source almost invisible from shallow angles. An excellent and cheap solution is to use highly recessed lights with standard, inexpensive designs. A PAR30S lamp in an ordinary (not "shallow") 5" or 6" ceiling can, with a trim that allows it to be installed at a respectable recess, can work very nicely. (That "S" is important. The whole point is that it's a "short neck" light, so the bottom surface is farther above the ceiling. And the PAR part is important, too -- PARs are reflectors, not floods, and they emit over a narrower angle.)
Here's a decent article about it:
https://www.agcled.com/blog/glare-and-ugr.html
As far as I can tell, this is almost completely ignored for residential and small business lighting, especially with LED lights from places like Costco and Home Depot. You do not want a bright light that emits over 180 degrees installed in plane with your ceiling.
> When it comes to light brightness, too much is just as problematic as too little Recently moved into a house with on/off light switches. Having the ceiling lights on full brightness was downright oppressive. I installed dimmer switches, and it's so much nicer it's hard to really convey.
How do you source lightbulbs? I have yet to find a reliable LED bulb that doesn't hum or flicker on a dimmer despite being advertised as "dimmable" . . .
Earlier quoted context omitted.
that's probably a problem with your dimmer switch, not the bulbs.
Explain. Isn't a dimmer switch just a variable resistor? Do you need fancy dimmer switches if you want them to work with LED bulbs?
The worst choice is a no-neutral-required forward-phase dimmer. Neutral-required forward-phase dimmers are usually better. Reverse-phase dimmers can be excellent for LEDs (but disastrous for magnetic transformers) and always require neutrals. Some dimmers can operate in both modes.
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There's a good chance its due to dry eye. If so, you need to blink more. Get an eye compress (heat it up in microwave, toss on eyes for 10 minutes). That can help release oils from glands onto your eyes. Artificial tears can help with comfort but wont solve the underlying problem--we don't blink (enough) when we focus on screens that are close to our face.
I don't think that is the case but I could be wrong. My eyes do not feel dry at all and drops or hot washclothes haven't made much difference. Maybe that compress you speak of is better though
https://www.amazon.com/Bruder-Activated-Recommended-Professi...
I got a fancier one from Tear Restore that has little cut outs, so I can see while using it (instead of keeping eyes closed). It may not work quite as good as the bruder, but it lets me get things done while using it.
Earlier quoted context omitted.
that's probably a problem with your dimmer switch, not the bulbs.
Explain. Isn't a dimmer switch just a variable resistor? Do you need fancy dimmer switches if you want them to work with LED bulbs?
Pretty much all dimmers now are TRIAC-based, which is a semiconductor that turns on partway through the AC wave, then turns off at the next zero-crossing, repeat. It chops the waveform so the light only gets power for a fraction of the time.
An incandescent bulb works largely the same with either type. (You may hear the filament "sing" on a TRIAC dimmer since the fast-rising waveform edge has a lot of harmonic content, but this is usually very faint.)
LED bulbs are non-dimmable by default. The typical job of a power supply is to ignore variations in the source and deliver uniform power to the load, and that's just what they do, driving the emitters at a constant brightness regardless of what the dimmer does, until it's letting through so little power that the poor thing just shuts off. Or flickers madly.
Dimmable LED bulbs are actually super tricky, because the power supply has to measure the distortions in the incoming waveform, interpret that as a dimming command, and use that to control the output to the emitters. Any jitter in the measurement sampling means the resulting brightness will bounce around. Any jitter in the waveform, which an incandescent might've ignored as long as the area-under-the-curve was equal, might be picked up by the LED power supply and misinterpreted as a changing dimming level.
It all sucks and we should abandon it immediately. LEDs should be driven with DC. But there's an awful lot of installed fixtures to keep us from that utopia.
> When it comes to light brightness, too much is just as problematic as too little Recently moved into a house with on/off light switches. Having the ceiling lights on full brightness was downright oppressive. I installed dimmer switches, and it's so much nicer it's hard to really convey.
How do you source lightbulbs? I have yet to find a reliable LED bulb that doesn't hum or flicker on a dimmer despite being advertised as "dimmable" . . .
[0]: https://www.lutron.com/europe/Service-Support/Pages/Technica...
A big thing not often spoken about with eye strain is dry eye caused by the lack of blinking due to focusing on screens too close to our face. This is an evolutionary phenomenon--close dangers cause extreme focus without blinking. Extreme focus on close items reduces our blinks. Our eye lids have glands in them that release oils on your eye with each blink. These oils help prevent the watery part of your tears from e…
Interesting. Could an external stimulus trigger a subconscious blink?
The web app can trigger a notification if your blinks / minute drop too low. Only challenge is modern browsers throttle websites that aren't visible, so the blink counting gets messed up.
A big thing not often spoken about with eye strain is dry eye caused by the lack of blinking due to focusing on screens too close to our face. This is an evolutionary phenomenon--close dangers cause extreme focus without blinking. Extreme focus on close items reduces our blinks. Our eye lids have glands in them that release oils on your eye with each blink. These oils help prevent the watery part of your tears from e…
Interesting. Could an external stimulus trigger a subconscious blink?
you could set something up where a water gun squirts you on a random interval between 2-5 minutes. heh i think i would kill someone if they did that to me.