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The subpixel-AA debacle and font rendering
- Thread starter mathcolo
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It is, but I (and many) also use it generically to indicate a display with the same resolution as a retina display. When it comes to scaling, it doesn't matter who makes the display, it matters what its resolution is. So if you have a 27" iMac (which has a 5k Retina display) and attach, as an external display, a 27" LG 5k (which is also a retina display, in the sense that it has retina resolution, i.e., the same number of ppi for the same display size), both will scale identically.
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I have a 1080p monitor (at the moment) and fonts look AWFUL. They're great on Windows and Ubuntu, however, so I don't understand why my Mac fonts look so bad. Something to do with "retina" displays, perhaps? I'm tempted to buy a 4K monitor just to fix this issue...
Happy to help. If it's within your budget (~$1300), and your Mac is new enough to drive it, I believe the best-performing option (other than the super-expensive 6k Apple Pro display) is the 27" 5k LG. I've not used it myself but, in addition to being retina resolution, I believe it has the same panel used on the 27" iMac. Essentially, if you like how Catalina looks on a 27" iMac, then you should like this as well, since the two should look the same (unless there are calibration differences, which you can adjust yourself).
Apple actually sells this on their website, but it can also be obtained from other sources, like B&H photo:
LG UltraFine 27MD5KLB-B 27" 16:9 5K IPS Monitor
Buy LG UltraFine 27MD5KLB-B 27" 16:9 5K IPS Monitor featuring In-Plane Switching (IPS) Panel, USB Type-C | Thunderbolt 3 Inputs, 5120 x 2880 5K Resolution, 1100:1 Static Contrast Ratio, 500 cd/m² Brightness, 178°/178° Viewing Angles, 14 ms Response Time (GtG), 60 Hz Refresh Rate, 1.07 Billion...
I've not heard any complaints about Catalina's text rendering from people using retina resolution monitors.
The second-best option would be a 27" or 24" 4k, which are in the $500 range.
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That's an extremely expensive budget :/ I've been a PC gamer all my life and I've never spent so much on a screen.
Yup. The Ultrafine is quite pricey, IMO.
Unfortunately, there are very, very few choices if you want a true "Retina" display.
However, you can get 4K displays for ~$300 now, like this $288 28-inch one. That's a ppi of 157, which is well below the ~200 you want for macOS's Retina scaling, but 1) depending on how far away you sit from the screen, you might consider that good enough, and 2) you can probably scale it a little further. Maybe even to 2560*1600@2x, which would be 216ppi.
Or you can get this $340 23.8-inch one. 188 ppi is a bit closer. You'll probably still want to scale.
Scaling blurs the resulting image a little (but far less than a 1080p 28-inch screen would), and also taxes the GPU, so your mileage may vary on performance.
Yup, that's the problem with the changes Apple keeps making in how they render text. They keep forcing upgrades to successively more expensive monitors.
Up through Snow Leopard (10.6) text looked good on my 94 ppi Dell 2408WFPb (24", 1920 x 1600) monitor. But starting with 10.7 (Lion), I found you needed ~130 ppi (the resolution of my 2011 15" MBP with the high-res screen option) for text to look good, which would have required me to find a 24" WQDH (2560 × 1440), which I'm not sure were even available then (nor do I think my MBP could have driven it). So I stuck with Snow Leopard until 2015 (well past its security support end date), when my purchase of a 2014 MBP forced me to upgrade the OS to Yosemite (10.10)
By then I was due for a new monitor, and fortunately Yosemite looked good with a 160 ppi 27" 4k, which I was able to purchase for a reasonable $500. But now I'm in the same boat -- just as I did with Snow Leopard, to avoid headaches from blurry text, I'll have to stick with 10.13 (High Sierra) well past its security support ending date until I can afford to buy both a new laptop and monitor (even if I could afford the 5k, my laptop is too old to drive it).
Yes, you can re-enable subpixel rendering on Mojave, but it doesn't look as good (at least to my eye) as it did natively on High Sierra. Probably High Sierra was optimized to look good with subpixel rendering, while Mojave (understandably, since it was disabled there by default) was not.
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All that and it's 60hz, which is unacceptable for fast moving games ...
FWIW I bought a ASUS ROG XG279Q 1440p monitor and this issue is not nearly as bad as my similarly pixel sized Dell U3417W (ultrawide 1440p that is curved). Can't tell you why.
Finally, at one point I bought the UltraFine 5K and returned it because my 2017 MPB ran hotter than hell when running it (and it was expensive). I will admit it looked amazing and the colors were excellent for photography. My ASUS had good colors according to the reviews. Can't have it all.
Maybe it depends on the monitor. Maybe my eyes need checked.
That's correct. High Sierra is the last OS to incorporate subpixel rendering natively.
It can be added back using a Terminal command in Mojave, and many feel that improves Mojave, but it still doesn't make it look quite as good as High Sierra. I would guess that is because High Sierra was built to work with subpixel rendering, while Mojave was not, but I don't know the exact reason. I just know that when I tried Mojave with the Terminal hack, it improved things, but text was still more fatiguing to read than in High Sierra.
You can test yourself whether you do or don't mind the change in the newer OS's. Just create a new partition (I don't know what the minimum is, but you don't need that much space -- I used 100 GB, so I'd also have room to install apps and test how they worked, but I think you can do it with much less), and install one of the newer OS's on it, and see for yourself. That's what I did before upgrading, which made me decide not to upgrade.
Yup, I did that with Mojave—tested on a partition. I tried some Terminal hacks including increasing the font weight (like so). I still didn't care for it and there aren't features in Mojave/Catalina that I would trade for bad font rendering. I do also have a '15 MBA currently running Catalina and the issue is subtle(?) but obvious on that machine. It really boggles my mind how Apple thinks this is OK.
I still run HS on a couple of Mini's. One has Server on it for a couple of projects. I'm too lazy to migrate that over to Linux container(s) on one of my Pi-holes for now, so it will keep on ticking after end of support in September.
Long ago I added subpixel rendering back on a Retina MBP running Mojave and it is a noticeable improvement,
Yeah, the 2015 MBA has only ~130 ppi (135 for 11", 128 for 13"), so it definitely would not look good with Mojave/Catalina. I've got 163 ppi on my 27" 4k, and even that's not good enough. You really need a retina (~220 ppi) display.
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defaults delete -g CGFontRenderingFontSmoothingDisabled
I posted this elsewhere, but just to add my opinion to this:
I completely agree that sub-pixel AA makes a significant improvement in text sharpness. I've observed this across Linux, Windows, and OS X.
Apple's reason/excuse for removing RGB antialising seems to be that it was too computationally expensive/difficult to keep track of it against non-white backgrounds. That was also Microsoft's excuse for removing Cleartype from Office versions later than 2010. However, Linux KDE seems to handle it just fine, but perhaps the desktop is rendered in a simpler way. I can imaging a problem on OS X if the background to where your text is, is a 'frosted' panel showing the desktop underneath i.e. a dynamically changing background.
Apple do have another trick up their sleeve - super sampling. Your desktop is actually rendered at twice your physical resolution, and then the GPU does hardware scaling to make it fit. This does make text sharper but still not as good as sub-pixel. This used to be enabled through a hack, but I believe in Big Sur it is default. If you go to About Mac > System Report and check the Displays/Graphics properties it should give you the framebuffer size. Is this twice your screen resolution?
I actually tried Apple's San Francisco system font in Linux with subpixel AA and it looks absolutely fantastic. Just a shame that Apple don't use it themselves.
In both Linux and Windows you can get a further increase in font sharpness using 125% desktop scaling. Worth it on a 1080p monitor in my view.
I believe Windows still uses Cleartype in their system font, and it does show.
So, currently my opinion is that the sharpness of Fonts on a non-retina monitor is Linux > Windows > Mac. I have a 1440p 24 inch from Dell and on Linux the fonts are really great. I would say nearly as good as a retina display.
I completely agree that sub-pixel AA makes a significant improvement in text sharpness. I've observed this across Linux, Windows, and OS X.
Apple's reason/excuse for removing RGB antialising seems to be that it was too computationally expensive/difficult to keep track of it against non-white backgrounds. That was also Microsoft's excuse for removing Cleartype from Office versions later than 2010. However, Linux KDE seems to handle it just fine, but perhaps the desktop is rendered in a simpler way. I can imaging a problem on OS X if the background to where your text is, is a 'frosted' panel showing the desktop underneath i.e. a dynamically changing background.
Apple do have another trick up their sleeve - super sampling. Your desktop is actually rendered at twice your physical resolution, and then the GPU does hardware scaling to make it fit. This does make text sharper but still not as good as sub-pixel. This used to be enabled through a hack, but I believe in Big Sur it is default. If you go to About Mac > System Report and check the Displays/Graphics properties it should give you the framebuffer size. Is this twice your screen resolution?
I actually tried Apple's San Francisco system font in Linux with subpixel AA and it looks absolutely fantastic. Just a shame that Apple don't use it themselves.
In both Linux and Windows you can get a further increase in font sharpness using 125% desktop scaling. Worth it on a 1080p monitor in my view.
I believe Windows still uses Cleartype in their system font, and it does show.
So, currently my opinion is that the sharpness of Fonts on a non-retina monitor is Linux > Windows > Mac. I have a 1440p 24 inch from Dell and on Linux the fonts are really great. I would say nearly as good as a retina display.
In what OS's does Graphics/Displays show framebuffer size? I've got High Sierra, and it shows framebuffer depth only. Can you post a screenshot?
In Catalina under Hardware>Graphics/Displays, it shows for me
Resolution: 4096x2304
Ui Looks like: 2048 x 1152 @ 59 Hz
Framebuffer Depth: 24 bit Colour
Yeah, I see something like that as well. But you were saying you can check for supersampling by seeing if your framebuffer depth is twice your screen resolution. But the two have nothing to do with each other -- you can't ask whether "4096x2304 is twice 24 bit Colour" -- it makes no sense, because their units are different. One is measuring no. of pixels, the other the color depth. The framebuffer depth listed here just means that each of the three color subpixels will have 8 bits of color resolution (3 x 8 = 24). It has nothing to do with screen resolution.
By framebuffer size I meant resolution, not depth. Where is says "Resolution" this is also referring to the framebuffer.
Are there expected changes in Big Sur which should further degrade the quality of text or remove any font smoothing commands? I'm experimenting with a change from a triple 4k display setup to a single Ultrawide. While the lower PPI is noticeable at first, it isn't as tragic as I expected.
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