PWM Sensitivity or something else?

simplex

kc44135 But the lightbulb wasn't flickering or anything, just a bit dim.

Can you describe the devices with screens that you use, if you know what kind of backlight they have - it will be even better. And also the lighting in your home (LED, incandescence etc)

If computer - what monitor, grapfic card, windows build

If phone - which model, android / iOS version

kc44135

simplex Main TV is a Panasonic ST30 Plasma from like 13+ years ago. I also use a Nintendo Switch with LCD screen, a Steam Deck with OLED screen, an Amazon Fire 10 Tablet, and a Samsung Galaxy A11 (yeah it's pretty old, lol), with a UI version of 4.1 and on Android 12. The lights in my home are all LED based. My Computer is actually just a Samsung Chromebook 4, I don't really know the screen type for it but I assume it is LCD. I've had all these devices for years with no issues and then out of the blue, can't use them for more than a few hours a day without literally getting sick. I would say the Tablet, Chromebook, and Switch do still feel the most comfortable overall.

simplex

kc44135

I was thinking, old displays get blue-tint because green/red peaks become smaller, I was wrong.

The issue in old devices, is blue peak grow up

The upper test show, +10% to blue peak in 2000 hrs

I mean, old "safe" device can be dangerous in terms of blue peak which irritates the cones in the retina

The joke is, new devices use dithering/FRC and it make it uncomfortable to use

But old devices has increased blue peaks which is also not good.

Try not to use LED / OLED screens and lights for a week, just to check does they cause you discomfort. I am personally found the "great sunlike" LED spectrum with big red peak also annoys me:

WhisperingWind

kc44135

The reasons can vary. For instance, I believe that the cause of my problem is instability in the cervical spine, which causes strong sensitivity to light and flickering (however, I don't have headaches). When I consulted ophthalmologists, they couldn't find anything, but one of the neurologists suggested an X-ray of the cervical spine with functional tests and was able to identify the issue.

The cervical spine contains nerves that can influence various functions, including those related to vision and eye movement. If a nerve is compressed or irritated, it might lead to symptoms such as photophobia (sensitivity to light). I'm sure that sensitivity to flickering has the same root.

Try consulting a neurologist.

kc44135

WhisperingWind Thanks, I have checked with Eye Doctors and the eyes are ok, and yes it seems to be a general sensitivity to lights. I was actually in a store with a bunch of bright lights and felt downright woozy. Yeah, I've got a Neurology appointment, but it's not until the end of May. I was told it's because "there's lots of young people with light sensitivity and headaches these days", whatever that means. 🙁

kc44135

simplex I have taken breaks from screens for a few days, although not as long as a week. Also, it's like impossible to get away from screens these days. Heck, I'm typing this on a screen, lol. But yeah, it seems like screens are not actually the only source of discomfort, they're just kinda the worst source of discomfort atm, but I will feel weird symptoms with other stuff too. It does seem more like a general Photobia/light sensitivity, I guess.

Also, all of this is like drastically worse if I'm say, looking at a bright light or screen. Trying to play the Silent Hill 2 Remake in a dark room on my PS5 (something I've done with loads of games before) left with me full on vertigo for hours and a headache that lasted days before it calmed down. I get those same symptoms with a better lighting, but drastically less so. It's more an aching around the eyes a bit of lightheadedness in comparison. Still bad, but not as debilitating.

Anyways, I will try those light bulbs, who knows maybe it can help? 🙂

Also, for newer TV's, I was looking around a bit and I saw there is a killer sale on LG OLEDs right now, specifically the B4. Supposedly it has no PWM dimming and emits less of that blue light stuff than ye Old Plasma (despite being brighter, can't say I understand how that works, lol). Maybe worth a shot, since the store is good with returns? Idk what the reputation of LG OLED TVs is like for people here, aside from the OLED phones apparently being nightmarish.

simplex

At least, try to use 2800k temperature LED lamps without flickering. They almost always have really low blue peak:

simplex

kc44135 Maybe worth a shot, since the store is good with returns?

There are no general tips here, because you have what we call a "habit" with your personal lighting sources (lamps, screens). So if there is an opportunity to return the goods, why not? In my country, this is impossible (only if there is a quality defect, and then you need to prove it and almost gather a pro-team)

WhisperingWind

kc44135

Also, for newer TV's, I was looking around a bit and I saw there is a killer sale on LG OLEDs right now, specifically the B4. Supposedly it has no PWM dimming and emits less of that blue light stuff than ye Old Plasma (despite being brighter, can't say I understand how that works, lol). Maybe worth a shot, since the store is good with returns? Idk what the reputation of LG OLED TVs is like for people here, aside from the OLED phones apparently being nightmarish.

I haven't encountered OLED displays that don't flicker (although technically they don't use PWM). In 2018, I had an LG 55B8 OLED TV. I couldn't watch it for more than an hour without experiencing eye strain.

However, we all have different sensitivities in our eyes, so it's impossible to give a definitive recommendation. In such cases, it's better to choose something expensive only if there is a guaranteed money-back option or the possibility to sell the equipment with minimal loss in value.

P.S. It is also necessary to mention dithering here. In fact, some dithering algorithms affect my eyes more than backlight flickering, regardless of whether this flickering is caused by PWM or other factors. Dithering is a technology that allows for emulating a broader color gamut than the display actually has. Some types of dithering can cause a flicker-like effect, such as temporal dithering. Dithering can also be present in OLED displays. It may not depend on the display at all and could originate from the computer's graphics card or something similar within a TV.

kc44135

WhisperingWind Thank you for this information. The TV was on sale ($600) and the store (Best Buy) is really good with returns and such, so I have decided I'll give it a shot. I had wanted an OLED for a long time (screens hadn't been giving me problems until a few months ago), so this wasn't solely based on the eye stuff. Hopefully it will be alright, but as you said, it seems like there is no way to know without taking the plunge, unfortunately.

Also, for dithering, you say it can be caused by content rather than the TV, but how would I know if it is happening or causing me issues?

choqpi

kc44135 Hi. I think your problem is similar to mine.

I described my case HERE

In short: I have been using OLED screens (Steam Deck, Nintendo Switch) for many months and they have not caused me any problems with my eyes. One day, suddenly, they became unbearable. Why? I still don't know. Before this happened, I tested several phones that gave me headaches and eye pain (Samsung OLEDs).

Unfortunately, I suspect that for some people (me, maybe you too) staring at the PWM screen makes the symptoms worse over time or causes them to appear. Covering one eye helps. It's better than nothing.

kc44135

choqpi Thanks for the response. Just to be safe for the time being, I'll be trying to reduce/avoid watching screens with PWM untiI I have a better understanding of what is happening.

WhisperingWind

kc44135

Also, for dithering, you say it can be caused by content rather than the TV

Not exactly. Dithering directly depends on the hardware and software. There are many dithering algorithms, but in my experience, the algorithms that cause significant eye strain are implemented in hardware (dynamic dithering). Software can manage the enabling or disabling of certain algorithms by instructing the hardware.

When it comes to a computer, dithering can originate from the graphics card or the display. Or from both.

In my experience with televisions, it's enough to know whether the TV display uses dithering. If it doesn't, there's a high likelihood that the TV's video chip won't perform dithering on its own. However, as I mentioned, it's always a risk since we almost never have the necessary information about the TV circuitry.

WhisperingWind

kc44135

but how would I know if it is happening or causing me issues?

You should check reviews to ensure that the TV doesn't have FRC, as this usually indicates temporal dithering in the case of a display.

FRC stands for Frame Rate Control, a technology used in displays, including TVs and monitors, to enhance color depth. It works by rapidly switching between different color shades to create the illusion of a greater range of colors. This is particularly useful in displays that natively support fewer colors, such as 6-bit (8-bit) panels, allowing them to simulate 8-bit (10-bit) color depth. By using FRC, these displays can show smoother gradients and more accurate colors, improving the overall viewing experience.

It's very difficult to know in advance how much a device will affect your eyes. It's all individual and depends on the person. I remember when I bought a used MacBook Pro 2017 15". We sat in a cafe for 30 minutes, and I worked with it the whole time (I was buying a used item), and there was no hint of problems. But at home, after 10 minutes, I already felt very strong eye strain. Lighting conditions matter (it's usually much brighter in a store than at home), as well as how often a person looks away from the screen: in the cafe, I looked away more often to talk to the laptop seller, etc.

beyondthelight

kc44135

You can get or make an incandescent backlit monitor, incandescent light doesn't cause strain

kc44135

beyondthelight I haven't heard of this display type, but will look into it, thanks!

kc44135

WhisperingWind Yeah, that's definitely the case for me too. The better lit the environment, and the more breaks I take, the better my eyes tend to do over time. Also, thanks for the information on dithering. As I'm taking a gamble on an LG OLED getting delivered in a few days, would you know if those TVs usually use any dithering?