hello elektrobank and others
I stumbled upon this post because I am having the exact same problem you described. A bit of a background: I have worked on iMacs and Thunderbolt Displays, MacBooks and Macbook Pros since 2008 on a daily basis. I use these machines privately and at my work. I wear glasses for driving, reading and all computer related work.
I started noticing the same problems and symptoms for the first time, when I purchased a glossy screen MacBook Pro in 2008 (New Unibody Model). At the time I did not know what to make of it and didn't blame the computer or the display. I just felt uncomfortable and hurt in my eyes. I returned the MacBook Pro and got the white Macbook. It was much better and I was happy (semi-glossy display, no LED backlight afaik).
In 2010 I started work where I sat in front of a 21.5" iMac (2010) all day. There was harsh fluorescent lighting in the office, which I soon blamed for having these eye pains, problems, etc. I noticed that turning down the fluorescent lighting and installing a halogen, warm desk lamp helped somewhat, for a while. I read about how fluorescent light and LED switch/flicker at a different Hertz rate and I concluded at that time, this was the problem. The varying frequencies of the different light sources, including the iMac backlight LED.
Moving on, I purchased a late 2013 iMac for my personal use. I realised that even in mixed light, daylight and other scenarios the problem persisted. Eye strain, blurry vision, all what you describe, sometimes more sometimes less. But now, since I started editing photographs a lot more, I noticed the floaters also (not only while looking at the screen, but also in blue skies, white surfaces, etc). I got scared so I went to my doctor, he checked my eyes and told me that my eyes were fine. He told me the floaters are a typical sign of ageing. I just turned 30 at that time, so I was not sure what to make of it. He told me some people have more, some less and advised me, if someday I would see flashes I should consult him or the hospital immediately, as this could be a sign of retina detachment. He explained how a larger than usual number of floaters could be an indicator of more severe conditions, I should just watch it. This was 4 years ago and nothing of the sort has happened since. In conclusion, I was not really satisfied and still unsure how to solve my problem, especially when working on the iMac. I noticed that the worst eye strain I get was by working on large excel sheets, or reading long black on white texts (like this one:). I could not do it for more than 10-15 minutes before needing a break.
Then I purchased a NEC MultiSync PA271W to use as my main monitor. I put the iMac on the floor (looked very odd) and worked exclusively on the NEC monitor for a while. My eyes felt much better. I reason this by the following characteristics compared to the iMac (late 2013) screen:
- Matte display
- Less aggressive LED backlight (possibly also better LED tech)
When I switched jobs I got to work with a Thunderbolt Display & rMBP. The the eye strain came back, and got worse. To put this in perspective, the Thunderbolt Display at work and my previous iMac late 2013 at home had similar display technologies, no 5k yet. I'll get to that in a minute though...
I started to accept the eye strain, disregarding the floaters and getting by just taking more short breaks and regular eye exercises (blinking, looking in the distance, etc). This was no long-term solution but it helped reduce the problem briefly.
A few months ago I started my own company. I used a rMBP 2013 as my main driver and got an excellent condition Cinema Display 30" to use it with. I was very happy. Little to no eye strain, no glare or reflections, great big display. Two weeks ago the display started to act up and cause all kinds of problems, like it has reached its end of life. Vertical coloured lines, blinking pixels, graphic glitches, etc.
As I was in the market for a new computer anyway, I jumped the gun on deal for the new 2017 iMac 5k last week. I set it up, calibrated the display multiple times with an i1Display & i1Profiler, measured the ambient light, measured the black point, contrast ratio... you name it. I made multiple custom calibrations based on local lighting conditions, adjusted the lights, played around with natural daylight, different brightness settings on the iMac, different white point settings, moved the computer away and to the window, etc.
Eye strain and blurry vision is back with the 5k!
The floaters I also had without using iMacs so I do not think they're related. I believe that when your eyes are struggling to cope, the floaters are just made much more visible.
To conclude this lengthy post, I can confirm that you are not the only one with this problem. I can also confirm, this problem, for those that encounter it, is not only apparent with the 5k iMac. In fact, at least for me, it was noticeable and severe on Macs since the LED backlight craze got started.
A few tips what you can try, that may or may not help (my opinions):
- adjust lighting, position of iMac to minimise glare
- do not place iMac in front of a window (so it is backlit by daylight)
- calibrate the display and adjust the color temperature to match the ambient light (warmer tone for light source as well as display)
- use desk lamps, not overhead lamps
- get glasses which reduce the amount of blue light from LEDs (I got those a couple of months ago, it helps!)
If nothing of this helps, get an ugly but excellent photo-centric hardware-calibrated display from a brand like NEC or EIZO with a matte screen. I can confirm, this will mitigate the eye strain and the blurry vision. This is not Apple's or anybody's fault in hardware. I believe some people are just more perceptive to Hertz or frame rate differences between lighting and LED backlight. You and me are some of those...
The floaters are here to stay. You may want to exercise, adjust to a healthy diet, cut down on caffeine, alcohol and nicotine to reduce the floaters. This will definitely help. I do not believe that the display has much to do with the floaters. It's possible that they emerge when your eyes are "strained" more than not, but nobody can confirm or deny it, because nobody knows it. Even the doctors have no clue if external factors - such as computer / mobile screens (apart from nutrition, drugs etc) - can influence the amount of floaters one has.
I myself will try to use the 5k iMac for the coming months. If I can't make it work eye-strain-free, I might need to buy another NEC display for my office. It defeats the whole purpose of buying an all-in-one computer, but what can you do, when apple no longer makes current, headless desktop machines?
Wish you all the best and let us know your progress!
Cheers,
Bastian
