Hi guys,
The scaling & multi-monitor support in Windows 8 has been annoying me since I got my SP1, and continues to do so on my SP3. It seems so close to being awesome but falls short with a pretty severe usability flaw in my experience. I've also seen a few posts about 'blurry text' and other scaling issues so I thought I'd dig deeper into what's going on here.
Windows 8 itself supports high DPI displays and DPI scaling for apps that don't natively support high DPI. The latter are scaled by Windows using Bitmap scaling and this can lead to a clear, crisp image if it's done at integer multiples (e.g. 1x, 2x, 3x) but leads to blurriness at decimal multiples (e.g. 1.5x, 1.8x). OSX does a similar thing on the Retina displays by doubling the size of each pixel (i.e. a 2x multiple that creates clear text & images).
There's 3 categories of high DPI support that apps fall in to:
Unaware - the app has no idea about high DPI displays and without external scaling it would appear very small on the display
System-aware - the app knows about high DPI displays and can scale it's content to fit but it has no concept of scaling differently for different monitors. It takes it's 'scale factor' from an OS level property that's based on your main display. It seems that this value is effectively calculated once on login so even if you switch your main display after log in apps in this category still won't update to the new scale factor. Even if the OS value was updated dynamically the individual apps would still probably need to be restarted before they re-scaled.
A lot of desktop apps fall into this category including the Office suite and dev tools like Visual Studio.
Per-monitor-aware - the app knows about high DPI displays and is aware of the DPI of each monitor that it's displayed on so it can scale it's own content efficiently.
Modern/Metro apps & Internet Explorer are in this category and should always look clear & crisp
The biggest problem I have faced is in the 'System-aware' category when I plug in an external, lower DPI, monitor while I'm already signed in to my Surface. In this case things like Office and Visual Studio don't recognise that scaling is different per monitor and are in fact still scaled to the 150% (i.e. a 1.5x scale factor) required for my SP3 screen. Windows takes over and uses Bitmap scaling to reduce the app to 100% for my 1920x1200 24" LCD and that's when the text gets blurry.
To resolve that problem I have to re-login (by either logging out restarting). That's a bit of a pain really and makes my transition from laptop or tablet to desktop harder then I'd like. I have the SP3 dock and really 'docking' should just be dropping the SP3 in the dock and picking up where you left off. Instead I have to save all my work, close everything down and logout.
There are obviously also other, more traditional, problems that can cause blurry text & images on a monitor, using an analogue connection like VGA or S-Video instead of a digital one like DVI, HDMI or DisplayPort, modifying Windows settings like ClearType, running the screen at a non-native resolution or having it's on board settings misconfigured, but I think there's plenty of info out there on those so I won't go into it any further here.
Anyway, I thought this might help someone.
Microsoft TechNet reference here: Fixing blurry text in Windows 8.1 for IT Professionals
The scaling & multi-monitor support in Windows 8 has been annoying me since I got my SP1, and continues to do so on my SP3. It seems so close to being awesome but falls short with a pretty severe usability flaw in my experience. I've also seen a few posts about 'blurry text' and other scaling issues so I thought I'd dig deeper into what's going on here.
Windows 8 itself supports high DPI displays and DPI scaling for apps that don't natively support high DPI. The latter are scaled by Windows using Bitmap scaling and this can lead to a clear, crisp image if it's done at integer multiples (e.g. 1x, 2x, 3x) but leads to blurriness at decimal multiples (e.g. 1.5x, 1.8x). OSX does a similar thing on the Retina displays by doubling the size of each pixel (i.e. a 2x multiple that creates clear text & images).
There's 3 categories of high DPI support that apps fall in to:
Unaware - the app has no idea about high DPI displays and without external scaling it would appear very small on the display
System-aware - the app knows about high DPI displays and can scale it's content to fit but it has no concept of scaling differently for different monitors. It takes it's 'scale factor' from an OS level property that's based on your main display. It seems that this value is effectively calculated once on login so even if you switch your main display after log in apps in this category still won't update to the new scale factor. Even if the OS value was updated dynamically the individual apps would still probably need to be restarted before they re-scaled.
A lot of desktop apps fall into this category including the Office suite and dev tools like Visual Studio.
Per-monitor-aware - the app knows about high DPI displays and is aware of the DPI of each monitor that it's displayed on so it can scale it's own content efficiently.
Modern/Metro apps & Internet Explorer are in this category and should always look clear & crisp
The biggest problem I have faced is in the 'System-aware' category when I plug in an external, lower DPI, monitor while I'm already signed in to my Surface. In this case things like Office and Visual Studio don't recognise that scaling is different per monitor and are in fact still scaled to the 150% (i.e. a 1.5x scale factor) required for my SP3 screen. Windows takes over and uses Bitmap scaling to reduce the app to 100% for my 1920x1200 24" LCD and that's when the text gets blurry.
To resolve that problem I have to re-login (by either logging out restarting). That's a bit of a pain really and makes my transition from laptop or tablet to desktop harder then I'd like. I have the SP3 dock and really 'docking' should just be dropping the SP3 in the dock and picking up where you left off. Instead I have to save all my work, close everything down and logout.
There are obviously also other, more traditional, problems that can cause blurry text & images on a monitor, using an analogue connection like VGA or S-Video instead of a digital one like DVI, HDMI or DisplayPort, modifying Windows settings like ClearType, running the screen at a non-native resolution or having it's on board settings misconfigured, but I think there's plenty of info out there on those so I won't go into it any further here.
Anyway, I thought this might help someone.
Microsoft TechNet reference here: Fixing blurry text in Windows 8.1 for IT Professionals