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I recently purchased a Mac Mini.

I have it hooked up to my Samsung Syncmaster via a KVM.

The font is quite blurry. I have the monitor set to native resolution. I have font smoothing turned on, and the font's are still quite blurry.

My windows 7 machine looks perfect.

I disconnected the Mac Mini from the KVM and did a direct plug in and still blurry.

My Mac Mini takes an HDMI input, so I have to go DVI-HDMI with the adapter provided.

Am I missing something? Font smoothing is enabled (using OSX Lion).

Sample pics: enter image description here

Without: enter image description here

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Try taking a screenshot of some text with and without font smoothing and post a magnified crop here as an update to your question.

Font Smoothing

As I understand it, the way some Font-smoothing works is essentially by blurring the edges of the glyph. So it should be expected - to some extent.





There are several mechanisms for improving the appearance of fonts at low resolutions or low sizes. (e.g. Sub-Pixel Rendering) Not all of these are suited to modern LCD/LED displays.

Note that Sub-Pixel Rendering depends on the computer knowing the order and geometric arrangement of individual color pixels on the physical display. If this is wrong the results would be very poor.

pixel geometry

from Wikimedia, photo by Peter Halasz. (User:Pengo)


Since some decades ago, displays have communicated their capabilities back to the computer using a Display Data Channel on one wire of the VGA, DVI or HDMI connector. I don't know if this includes pixel geometry or if the system could operate at all with this connection broken, but it might be worth testing.


Update: In the example OSX screenshot images, the main problem is JPEG artefacts, here is an enlarged section:

OSX screenshot jpeg

All that blotchy muddiness is the result of JPEG compression. To compare font smoothing you need a lossless format without artefacts - PNG is a good choice.

P.S. subpixel rendering won't show up in screenshots made using the computer alone. You need to use a digital camera with macro capability.

Resolution and Font size

To achieve maximum legibility with an LCD display you should always set the resolution to the native resulotion of the display. To increase the size of lettering used in windows, desktop-icons, system-dialogues and in applications you should use other means. For example or screen magnification

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Thanks. I'll post some pictures when I get home tonight. – Jack Marchetti Sep 7 '11 at 15:49
posted two pics. – Jack Marchetti Sep 8 '11 at 2:31

Although other people wrote a long and informative explanation about subpixel rendering and antialiasing, I don't think this is caused by that.

I have a B2230HD monitor. I know how crisp images on Mac is. The blurry thing doesn't happen only to text but overall image.

However, when I boot into Windows 7 with Samsung's device driver for the monitor is connected, it displays everything very clearly.

I think this is due to device driver. Did you install a device driver for the Samsung monitor on your Mac? There is no device driver for my Samsung B2230HD monitor. So, it will use Apple's standard HDMI/DVI monitor driver.

Then, this kind of blurry image can be presented. This symptom is exactly same to the ones happened to my old monitors on Windows. When I used standard device drivers with support for proper resolutions for the old VGA/Super VGA, etc monitors, if the standard device driver supported those monitors' characteristics fortunately well, it displayed crisp images. however, usually it didn't. Then it displayed image like this which I see right now.

Samsung and LG manufacture great monitors and electronic devices. However, their S/W support is not as good as Sony's or American brands'.

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It's quite sad, since my macbook at work is so crystal clear. I knew I should've just gotten an iMac instead of the Mac Mini. Oh well, it's not so blurry that I can't even work with it. I think it might be time for a new Monitor though. – Jack Marchetti Oct 20 '11 at 20:29

On the B2230hd display, go to Input Selection, select the HDMI where you have connected your Mac Mini, change the name to "PC" and that is it!

Works just like a Cinema display.

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I don't have a B2230hd. It connects only with DVI, I'm connected to my mac mini using a dvi-hdmi adapter. Are you saying go to the settings on the Monitor and select PC? – Jack Marchetti Nov 3 '11 at 15:41
Either this is the placebo-effect (what it believe) or it really works, at least make sure to change source after applying this change. – idmean Mar 12 '15 at 17:32

DVI-HDMI adapter also can't be to blame. The signal is digital, so if the adapter was faulty, you would notice it as missed frames, not blur.

Blur is either due to anti-aliasing done by operating system or resolution being incorrect and monitor scaling the image in-the-fly. Make sure you have selected desktop resolution that's identical to the native resolution of the display.

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I can't keep the native resolution as I have pretty poor vision, however, even at native resolution the fonts are quite blurry. – Jack Marchetti Sep 8 '11 at 2:27

Two things:

  1. Make sure your HDMI to DVI adapter supports dual-link DVI.
  2. You can try this: defaults -currentHost write -globalDomain AppleFontSmoothing -int 2

The second taken from here. I personally had this problem because I was using a single link DVI cable. Switched to dual link & it got much better. Single link may be fine for anything under 20" on OS X, but anything above seems to need dual link.

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He's using native resolution so that can't be the cause of the problem. – Daniel Beck Jan 4 '12 at 2:52
Yes it can. Single link DVI doesn't have enough bandwidth for OS X displays. Native resolution has nothing to do with it. – churnd Jan 4 '12 at 14:59
Meant to say "..doesn't have enough bandwidth for larger displays on OS X." – churnd Jan 4 '12 at 15:11
Do you have references for what you write? Single-link DVI can handle 1280x800, the resolution of his screenshots. I have used DP-to-DVI converters with 1920x1200 displays without problem. You get problems when you connect single-link DVI to an e.g. 27" screen (2560x1440) but then you don't even get the native resolution as choice. – Daniel Beck Jan 4 '12 at 15:13
No, just experience. I just bought a Samsung 22" LCD (1650 x 1080) for my Mac Pro & with a single link DVI cable, the fonts were blurry. Switched to dual link cable & the problem went away. Converters are a different issue. It may also be dependent on the power of the GPU. Older GPU's & current Intel GPUs might not be up to snuff. I don't think you will find any documentation from Apple describing this either. They'll just say "It's not supported" &/or "Get an Apple Cinema Display". – churnd Jan 4 '12 at 16:53

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