Thank you so much for your post!
I had the same problem! Everything looked too small. But... How can I know if my display is using the RGB mode or the another one?
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Guide: Fixing External Monitor Scaling and 'Fuzziness' Issues with MBP and OSX
- Thread starter seb101
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Thank you so much for your post!
I had the same problem! Everything looked too small. But... How can I know if my display is using the RGB mode or the another one?
If Apple fixed their scaling factor to be "2", how come I can select between four different "scaled" settings on my retina MacBook Air, which start with "looks like 1024x640" and end with "looks like 1680x1050"? The native resolution of the display is 2560x1600 btw -- note how out of the four "resolutions" (resolutions look-alikes, rather) it offers me, only one corresponds to an integral scaling factor (that's 1280x800), and that one isn't even the default one (which is 1440x900)!
The scaling factor was indeed fixed to be "2" for the very first retina displays (in the iPhone 4 IIRC), but I believe it was never that simple on macOS (where retina was introduced a bit later). The old flexible Quartz UI scaling that you mention was something completely different btw, because it relied on rendering all UI elements as vector graphics. How the current scaling works I'm not completely sure, but my guess is that applications render into high-resolution backing stores which are then scaled as necessary by the compositor (i.e the window manager). How good that looks would then not depend on the output size, but rather on the resolution of the backing store.
In general, I want to remark I find your tone towards the OP is unnecessarily condescending. If you don't have anything helpful to say, why do you feel the need to comment in this thread at all? It's certainly not for you to decide whether his attempt at running his 1440p monitor with 125% UI scaling is sensible or not! And given that he opened the thread with a very detailed explaining of how to achieve this despite being unsupported, telling him in a condescending way that what he wants is unsupported is a tad absurd.
Because Apple's scaling is implemented as a two-step process. What you choose is a logical resolution (grid of logical pixels), say, 1024x640. The UI is then drawn to what Apple cals a backing buffer at twice the resolution, so 2048x1280. The drawing itself is done like I described in my previous post, that is, each logical pixel is mapped to a 2x2 grid of backing pixels, and what you get is essentially super sampling AA without the final averaging step (since the backing pixel grid itself is super-sampled). That is the first step. In the second step the backing buffer is drawn to the screen, using interpolation to map the backing pixels to real hardware pixels. If you choose "best for" resolution, the backing buffer and the hardware display map exactly, otherwise it is interpolated. For most resolution choices, the resolution of backing buffer is higher than the physical resolution of the machine, so image is actually drawn at a higher resolution. This ensures best possible image quality.
This two-step process allows one to emulate true scaling. The scaling factor is always 2, and that is something that algorithms can always rely on. But since you can manipulate the resolution of the backing factors, you get different mappings to the physical screen, allowing you to make the picture larger/smaller with little loss of actual spatial detail.
Note: nowadays it's a bit more complicated, because newer phones support scaling factors of 3, but the same logic applies.
It is a mixture of vector and bitmap graphics really. Frequently used vector shapes (like fonts) are pre-rendered at standard sizes to accelerate the final drawing. Same for standard UI controls like button borders etc. I don't know how (or if at all)the system changed when Apple decided to fix the backing factor to either 1.0 or 2.0, but Id'a seem that it made some optimizations easier to pull off, as you can always assume that, say, a button shadow has a specific size.
I am sorry if my tone came off as condescending. I was merely trying to point out that a) Apple doesn't give the user much official choice in the matter, since they are very opinionated with these things and b) that there are certain technical and aesthetic reasons why they force these limited choices on us. OP are of course free to do whatever they choose and one can "hack" the system by manipulating the logical resolution outside to what Apple exposes to users directly. Does not mean that it is officially supported or will result in best image quality.
Have MBP 15 2018 and can confirm: MacOS = a lot, lot issues with external displays...
1. You can use 2x scaling (so 24" 4K to FHD but it's too big, or 27" 5K => 1440p, it's ok) or see blurry/fuzzy fonts
2. One exception I now test is P2415Q - 4K on 24", so PPI is very big and on scaling to 1440p it's still ok (but not great)
3. You can't use Display Port daisy chain, because not, because it's Apple...
4. On non-HDPi everything looks terrible. Last time I tested 25" WQHD (1440p native) and on MacOS fonts were terrible, on Windows still ok.
5. Connect external display to MBP => force to use dGPU (Radeon => higher temperature, much more noise etc....
Now I consider going back to Windows laptop or just use Windows/bootcamp as primary system. As hardware, MBP is great, but software (MacOS) is.... agrr...
1. You can use 2x scaling (so 24" 4K to FHD but it's too big, or 27" 5K => 1440p, it's ok) or see blurry/fuzzy fonts
2. One exception I now test is P2415Q - 4K on 24", so PPI is very big and on scaling to 1440p it's still ok (but not great)
3. You can't use Display Port daisy chain, because not, because it's Apple...
4. On non-HDPi everything looks terrible. Last time I tested 25" WQHD (1440p native) and on MacOS fonts were terrible, on Windows still ok.
5. Connect external display to MBP => force to use dGPU (Radeon => higher temperature, much more noise etc....
Now I consider going back to Windows laptop or just use Windows/bootcamp as primary system. As hardware, MBP is great, but software (MacOS) is.... agrr...
Fantastic guide!
And yes, this VERY relevant for 2020. I helped my Father set this up on his new 49" LG 32:9 super-wide monitor.
And yes, this VERY relevant for 2020. I helped my Father set this up on his new 49" LG 32:9 super-wide monitor.
I've been looking around for this thread for a while, so seems like some of you are knowledgeable to help me. Here's my problem. I have a 2017 Macbook Pro 13" Retina. In Display Preferences, I used to set scaling to "More Space", but I found the fonts/windows too big. I wanted more space and discovered for first time that"More Space" looks like 1650 x 1050 resolution. To fix that, I found a utility, that let's you change the "looks like" to "2048 x 1280" which I find to be the perfect size for my eyes and density. I'm using "Display Menu Pro" utility to do that: http://displaymenu.milchimgemuesefach.de/about.html
Recently, I got an external 4K monitor, however, I'm back to the problem where OSX only allows "More Space" scaling, and wish it had "More More Space". The "More Space" scaling works best for about 2.5 browser windows / apps side-by-side. If only I could do the same thing to the external monitor that I did to the built-in one where I could change the "effective resolution" one level higher, I could get the space that I need and run 3 windows side by side. It's a 32" 4K monitor, so there's plenty of room.
Does anyone know of a way to change scaling for external 32" 4K monitor in same way I did it for internal retina?
Recently, I got an external 4K monitor, however, I'm back to the problem where OSX only allows "More Space" scaling, and wish it had "More More Space". The "More Space" scaling works best for about 2.5 browser windows / apps side-by-side. If only I could do the same thing to the external monitor that I did to the built-in one where I could change the "effective resolution" one level higher, I could get the space that I need and run 3 windows side by side. It's a 32" 4K monitor, so there's plenty of room.
Does anyone know of a way to change scaling for external 32" 4K monitor in same way I did it for internal retina?
Really frustrated with the font issue. I "upgraded" from High Sierra to Catalina and now my fonts are really unpleasant. I've tried the smoothing in System Preferences, I've tried forcing font smoothing with terminal (defaults write -g CGFontRenderingFontSmoothingDisabled -bool NO) and can't get anything to work. Why were my fonts just fine in High Sierra (and earlier Mac OS X) but now so screwed up? Philips Brilliance 272P (2560x1440, 27" DisplayPort).
kudos to OP. this is the most fun opening post I have ever read on any subject. period.(writing skills made it too much fun)
though I wonder why he hasn't corrected the glitches for people to understand the requirment better and help if they are able. I mean the whole 4k=2560x1440 but settings show its just a 1920x1200 display.
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sorry I did not understand your problem. you can already use 3 windows side by side with native 4k resolution on 32 inch screen. or as you put the more space option. see my example above.
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did you try your monitor osd for HDMI settings. that might be the culprit. look for options there. I think it has to be corrected to rgb display.
though I wonder why he hasn't corrected the glitches for people to understand the requirment better and help if they are able. I mean the whole 4k=2560x1440 but settings show its just a 1920x1200 display.
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sorry I did not understand your problem. you can already use 3 windows side by side with native 4k resolution on 32 inch screen. or as you put the more space option. see my example above.
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did you try your monitor osd for HDMI settings. that might be the culprit. look for options there. I think it has to be corrected to rgb display.
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no I meant color format rgb or Yuv? this will never be sRGB as that's a colourspace. most webpages are in sRGB only.
colourspace can't improve font. sRGB / Adobe RGB / Display P3 etc. depends on the content you wanna use.
After struggling with fuzzy text on a DELL P2418D (QHD) and a Benq "Mac compatible" PD2500Q (QHD) display and trying forced RGB mode etc, I finally found the following posts.
These explain the issue very clearly and provide a simple tool to create replacement display config (plist) files (which are located in Macintosh HD ▸ System ▸ Library ▸ Displays ▸ Contents ▸ Resources ▸ Overrides).
That tool and method plus the RDM app which reveals HiDPI modes (best text rendering) worked a treat.
The only snag is that macOS updates may overwrite your modified config files, so keep a copy in case you have to replace them again.
Kudos to the guy who figured it out (very clear explanation): Force HiDPI Resolutions for Dell U2515H Monitor
Display configuration file generator tool he created: PropertyList Parser and Generator
RDM app (just save it in Applications folder): RDM
These explain the issue very clearly and provide a simple tool to create replacement display config (plist) files (which are located in Macintosh HD ▸ System ▸ Library ▸ Displays ▸ Contents ▸ Resources ▸ Overrides).
That tool and method plus the RDM app which reveals HiDPI modes (best text rendering) worked a treat.
The only snag is that macOS updates may overwrite your modified config files, so keep a copy in case you have to replace them again.
Kudos to the guy who figured it out (very clear explanation): Force HiDPI Resolutions for Dell U2515H Monitor
Display configuration file generator tool he created: PropertyList Parser and Generator
RDM app (just save it in Applications folder): RDM
Okay so obviously I am deep down the rabbit hole having read to the end of this comment thread (OP was very entertaining and I identify a lot with their mindset), and I've learned quite a bit from these detailed replies even after trying for an even longer time to solve a similar issue on my own, yet I am still stuck. I don't really know where else to post this, and seeing the depth of this thread finally made me stop to make a plea for help.
I have a 4K Philips TV (yes, actually 4K... 3840x2160 and my macbook Pro 2018 can display native 4K on it @30Hz, TV model 55PUS7809), and would like 1080p HiDPI. A nice even upscaling factor of 2.0 should be easy enough to implement right? Wrong.
Before anyone asks, I have tried all the "grandpa-level" fixes such as holding option while clicking the scaled menu in Settings, and enabling HiDPI mode with the sudo terminal command.
Even after following a similar process as in moc99's post above (enabling HiDPI mode with sudo command, generating and copying plist files to the right path in both /System/Library and /Library folders, installing RDM, rebooting at every step of the process), I cannot force the HiDPI 1920x1080 resolution. It appears in the RDM menu list but doesn't do anything when I click on it.
I even downloaded the trial version of SwitchResX to see if it somehow was doing something I missed. It does create a new plist file in the /Library directory but has the same problem: the HiDPI 1920x1080 resolution is there (at several Hz options) in the list but it doesn't do anything which I click on it. (sidenote: it suspiciously works for >30Hz, so only resolutions that aren't supported for 4K output and results in regular, blurry 1080p)
Consulting the SwitchResX FAQ page led me to this gem:
Sure enough, I found this error message in my console after trying to set the 1080p HiDPI resolution.
Even the developer of the premium paid version of this whole hoop-jumping process (which is supposed to do everything seamlessly and is constantly updated), admits that there is an unavoidable "bug" in macOS that is preventing people from using the Retina HiDPI image rendering on non-Apple-approved TVs, specifically for the most common and actually-likely-to-work upscaling resolutions (50% and 25% of 4K). I don't think that this is a coincidence... rather Apple has put this in place so that people are forced to suffer with either tiny or blurry text unless they buy a Retina-compatible monitor or TV. If someone has a reasonable alternative explanation, I'm all ears, but to me this seems like a classic marketing gimmick.
In the meantime, I'll see if I can go yet another level deeper (already invested so much time at this point that its more of a vendetta than anything) to try to disable whatever MacOS boot process that is specifically disabling the 2X scaled HiDPI resolutions in the override folder upon startup. If anyone has any links to similar threads I'd be much obliged. I haven't tried the EDID overwrite but I don't think this is related to my specific issue.
I have a 4K Philips TV (yes, actually 4K... 3840x2160 and my macbook Pro 2018 can display native 4K on it @30Hz, TV model 55PUS7809), and would like 1080p HiDPI. A nice even upscaling factor of 2.0 should be easy enough to implement right? Wrong.
Before anyone asks, I have tried all the "grandpa-level" fixes such as holding option while clicking the scaled menu in Settings, and enabling HiDPI mode with the sudo terminal command.
Even after following a similar process as in moc99's post above (enabling HiDPI mode with sudo command, generating and copying plist files to the right path in both /System/Library and /Library folders, installing RDM, rebooting at every step of the process), I cannot force the HiDPI 1920x1080 resolution. It appears in the RDM menu list but doesn't do anything when I click on it.
I even downloaded the trial version of SwitchResX to see if it somehow was doing something I missed. It does create a new plist file in the /Library directory but has the same problem: the HiDPI 1920x1080 resolution is there (at several Hz options) in the list but it doesn't do anything which I click on it. (sidenote: it suspiciously works for >30Hz, so only resolutions that aren't supported for 4K output and results in regular, blurry 1080p)
Consulting the SwitchResX FAQ page led me to this gem:
Sure enough, I found this error message in my console after trying to set the 1080p HiDPI resolution.
Even the developer of the premium paid version of this whole hoop-jumping process (which is supposed to do everything seamlessly and is constantly updated), admits that there is an unavoidable "bug" in macOS that is preventing people from using the Retina HiDPI image rendering on non-Apple-approved TVs, specifically for the most common and actually-likely-to-work upscaling resolutions (50% and 25% of 4K). I don't think that this is a coincidence... rather Apple has put this in place so that people are forced to suffer with either tiny or blurry text unless they buy a Retina-compatible monitor or TV. If someone has a reasonable alternative explanation, I'm all ears, but to me this seems like a classic marketing gimmick.
In the meantime, I'll see if I can go yet another level deeper (already invested so much time at this point that its more of a vendetta than anything) to try to disable whatever MacOS boot process that is specifically disabling the 2X scaled HiDPI resolutions in the override folder upon startup. If anyone has any links to similar threads I'd be much obliged. I haven't tried the EDID overwrite but I don't think this is related to my specific issue.
Hi I have the same monitor and it looks like crap haha, I was trying to follow your tutorial to fix it but I ran into some issues. Would you happen to have somewhere where I can DM you so you can help me out to make text look a little better? I would appreciate it a lot. Thanks. You can DM on twitter at @juanchobb_
So, your Macbook Pro - throttling sensitive CPU/GPU is rendering 75% more pixels because you want a 14.29% UI zoom (or 12.5% less screen real-estate)
Am I the only one that can't help it but laugh at this practice?
Scaling is not supposed to work like that. Even RDM, the tool, is not advertised for this but the exact opposite (claim back screen real-estate)
A proper scaling use example is that of Retina Macbooks. On their default setting (which is scaled) you get:
12.5% more pixels rendered for 12.5% more space
Plain and simple
Thank you seb101 very very very much. This last 8 awesome points saved me a lot of time.
I bought a portable 15 inch display with FullHD resolution to connect to my 15 inch MBP. With FullHD resolution the UI elements were in awful sizing, like a way smaller then the elements in the build-in MBP retina display. I had two options in default settings, 1080p and 720p. 720p was very nice in sizings, but the overall quality of the UI elements became worse. I installed this RDM tool, in MBP default settings set to 1080p, and via RDM set to 720p. And it worked all good.
Here is the first screenshot, set 720p in MBP default settings.
And the second screenshot, set 1080p in MBP default settings, then 720p via RDM tool.
At the first one you can see it was truly smaller resolution, it was 720p on my FullHD display. But the second screenshot shows that it has bigger resolution, it is now 1080p again, but scaled as if was in 720p.
So as a result I got scaled UI elements without loosing the FullHD resolution and so the image quality.
Thanks you seb101 for posting these great directions for a work around for blurry fonts resulting from DPI or native resolution scaling. I have a situation with a 2017 Macbook Pro with a broken internal 1440p display. It's using an external 1080p display and everything is blurry due to down scaling from the retina display native resolution which is what OS X is using. Is there a quick fix to simply change the native resolution of OS X to 1080p rather than keeping (2.5k) 1440p as the native resolution?
You did a good job explaining all the steps of what you did, but I would like to explain in simple terms what is happening. In the past the operating system always operated at the native resolution of a display. If you had multiple displays connected to your computer with different resolutions, they wouldn't always match up perfectly but nothing was ever blurry or scaled. Today there is a thing, which I won't call a feature, that is called native DPI scaling or possibly native resolution scaling. It makes it so that regardless of whatever resolution display that you connect to your OS X (or possibly Windows 10) computer, everything on the screen will always be filled to exactly the same size. If you have a 1440p 13" display on your laptop, OS X will operate with 1440p as the native resolution, and if you plug in a 1080p display, the 1440p resolution will be down scaled to 1080p. Scaling graphics is a very ugly process when the lower resolution is close to the source resolution. There are mathematical methods of scaling an image down but there are limitations. The 1080p display will have pixels that are in between the pixels on the 1440p native resolution, and the scaler has to figure out how to fill those pixels based on surrounding pixels on the 1440p native resolution. This makes sharps edges such as fonts look terrible.
The work around you proposed is to force the native resolution of OS X to some very high resolution such as 2160p or 2880p or higher, then scale that down to the 1440p display panel and the 1080p external display. The scaler will work perfectly when the higher resolution is an exact multiple of the lower resolution. For example, 720p and 1080p scale perfectly in to 2160p, but 1440p doesn't. Unfortunately your work around has performance issues resulting from operating at very high native resolution. The lowest resolution that perfectly scales in to 1080p and 1440p is 4320p, also called 8K. That's a very high native resolution to run your system at and there will be obvious performance penalties.
You did a good job explaining all the steps of what you did, but I would like to explain in simple terms what is happening. In the past the operating system always operated at the native resolution of a display. If you had multiple displays connected to your computer with different resolutions, they wouldn't always match up perfectly but nothing was ever blurry or scaled. Today there is a thing, which I won't call a feature, that is called native DPI scaling or possibly native resolution scaling. It makes it so that regardless of whatever resolution display that you connect to your OS X (or possibly Windows 10) computer, everything on the screen will always be filled to exactly the same size. If you have a 1440p 13" display on your laptop, OS X will operate with 1440p as the native resolution, and if you plug in a 1080p display, the 1440p resolution will be down scaled to 1080p. Scaling graphics is a very ugly process when the lower resolution is close to the source resolution. There are mathematical methods of scaling an image down but there are limitations. The 1080p display will have pixels that are in between the pixels on the 1440p native resolution, and the scaler has to figure out how to fill those pixels based on surrounding pixels on the 1440p native resolution. This makes sharps edges such as fonts look terrible.
The work around you proposed is to force the native resolution of OS X to some very high resolution such as 2160p or 2880p or higher, then scale that down to the 1440p display panel and the 1080p external display. The scaler will work perfectly when the higher resolution is an exact multiple of the lower resolution. For example, 720p and 1080p scale perfectly in to 2160p, but 1440p doesn't. Unfortunately your work around has performance issues resulting from operating at very high native resolution. The lowest resolution that perfectly scales in to 1080p and 1440p is 4320p, also called 8K. That's a very high native resolution to run your system at and there will be obvious performance penalties.
Thanks, great writeup! Just got a MacBookPro for the first time ever, and got to this problem too. Mac would not let adjust scaling for external monitor, just the resolution. Set it to lower resolution for a few days, but the letters were blury and bulky, not crisp as i know it is when I worked with Windows machine. Yes, downsizing resolution is not the same as scaling.
I had this same issue today, after hours finally gave in and bought a 'mac compatible display' my monitor was a couple years old so I didn't really mind but I was pissed for a good few hours
I would like to inform you that what you describe is simply not true. Resolution and scaling on modern OSes doesn't work that way and they definitely don't use the same native resolution across every monitor.
Hints for further research:
"Why there is a differentiation of Retina and Non-retina displays and they don't simply use their pixel count as a spec?"
"Why does Apple advertise and use 5k as a resolution on their bigger size monitor displays?"
My Plugable 2x4k @ 60 hertz DisplayLink adapters gives you 3,008 x 1,692, QHD and many others that aren't fuzzy if you use the beta drivers. So DisplayLink has fixed what is still broken in macOS. My mini will do 3,008 x 1,692 clearly on the USB-C monitor but only 2K off the HDMI port.