Retina iMacs/Thunderbolt Displays

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Macrumors has a good overview on the next gen of Thunerbolt Displays and subsequent upgraded (Retina) displays for iMacs.

For the 21.5 inch iMac, a true "Retina" (doubling of pixels) would make it exactly 4k resolution (3840 x 2160 pixels) - and thus HiDPI mode would make the entire UI the same relative size, effectively 1920x1080, but incredibly sharp like the current MacBook Pro Retinas.

For 27 inch displays, it seems nearly impossible on many fronts to do anything higher than 4k, so they can't just double the pixels like they usually do. DisplayPort 1.2 standard used in Thunderbolt 2 only supports a maximum of Cinema 4K at 4096 x 2160 pixels. This means the 27 inch displays will also likely "just" be 4k. But in order to have a useable UI, the relative UI in HiDPI mode would actually be larger than the current displays.

It would essentially be the same situation you see between the iPad Mini and iPad air - same exact screen resolutions, just different sizes.

To me, the UI elements and text on current 27 inch displays is actually rather small, so I don't really see it as a terrible thing to sacrifice some screen real estate to run in HiDPI mode. Running at full resolution in 4k would be basically unusable, without a magnifying glass.

To get an idea, you can set your resolution on 27 inch to 1920x1080 and see what the relative size of the UI would be - imagine a "Retina" version of that.

I do not know if there is a way they could scale the UI to something in between as to not sacrifice as much real estate, and still call it "Retina".

My understanding is that OSX doesn't even yet have a setting for HiDPI mode for 4k displays, and that they just run at full scale, making most UI elements unusable.

Thoughts?
 
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You would almost think that they would have to make a non4k and a 4k if they do it in the near future, otherwise if anyone wanted to hook up one to their iMac you would have different looks on the screen completely. The other option is to update all of the iMacs to 4k but we know that will probably come in steps.
 
Macrumors has a good overview on the next gen of Thunerbolt Displays and subsequent upgraded (Retina) displays for iMacs.

For the 21.5 inch iMac, a true "Retina" (doubling of pixels) would make it exactly 4k resolution (3840 x 2160 pixels) - and thus HiDPI mode would make the entire UI the same relative size, effectively 1920x1080, but incredibly sharp like the current MacBook Pro Retinas.

For 27 inch displays, it seems nearly impossible on many fronts to do anything higher than 4k. DisplayPort 1.2 standard used in Thunderbolt 2 only supports a maximum of Cinema 4K at 4096 x 2160 pixels. This means the 27 inch displays will also likely "just" be 4k. But in order to have a useable UI, the relative UI in HiDPI mode would actually be larger than the current displays.

It would essentially be the same situation you see between the iPad Mini and iPad air - same exact screen resolutions, just different sizes.

To me, the UI elements and text on current 27 inch displays is actually rather small, so I don't really see it as a terrible thing to sacrifice some screen real estate to run in HiDPI mode. Running at full resolution in 4k would be basically unusable, without a magnifying glass.

To get an idea, you can set your resolution on 27 inch to 1920x1080 and see what the relative size of the UI would be - imagine a "Retina" version of that.

I do not know if there is a way they could scale the UI to something in between as to not sacrifice as much real estate, and still call it "Retina".

My understanding is that OSX doesn't even yet have a setting for HiDPI mode for 4k displays, and that they just run at full scale, making most UI elements unusable.

Thoughts?

Quote: "Though prices on 4K panels have begun to drop, the graphics requirements needed to drive high-resolution displays may lead Apple to continue to offer either the current Apple Thunderbolt display or a redesigned version of it in order to offer a product compatible with the MacBook Air and other Macs lacking the graphics capabilities to drive the number of pixels in an upgraded display."

I think the above paragraph from your MR Thunderbolt display link, is a plausible explanation for the delay. Also Apple wouldn't sell the 4K Sharp display in their stores if their own upgraded displays were imminent.

If that premise turns out to be correct, upgraded displays from Apple could make an appearance by the summer.
 
Quote: "Though prices on 4K panels have begun to drop, the graphics requirements needed to drive high-resolution displays may lead Apple to continue to offer either the current Apple Thunderbolt display or a redesigned version of it in order to offer a product compatible with the MacBook Air and other Macs lacking the graphics capabilities to drive the number of pixels in an upgraded display."

I think the above paragraph from your MR Thunderbolt display link, is a plausible explanation for the delay. Also Apple wouldn't sell the 4K Sharp display in their stores if their own upgraded displays were imminent.

If that premise turns out to be correct, upgraded displays from Apple could make an appearance by the summer.
Right - they will probably still sell the legacy Thunderbolt Displays and iMacs at the lower resolutions at lower price points.

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You would almost think that they would have to make a non4k and a 4k if they do it in the near future, otherwise if anyone wanted to hook up one to their iMac you would have different looks on the screen completely. The other option is to update all of the iMacs to 4k but we know that will probably come in steps.
Yeah - if it is easy enough from a manufacturing standpoint they could just put the lower(current) res displays into whatever the new form factor is (for Thunderbolt Displays and iMacs).

Or, they will just continue to sell the older models as is - like the Macbook Pros, iPads, etc.
 
There was an article on this topic a month ago - https://www.macrumors.com/2013/12/3...e-the-wild-west-some-4k-monitors-unsupported/


You can use tools like SwitchResX (or Quartz Debug or the necessary Terminal command) to enable a 1080p HiDPI mode, but then you end up with insanely low point density of around 68 PPI. Unfortunately it doesn’t appear to be possible to define your own HiDPI modes in OS X, you have to rely on those that Apple officially supports. I tried creating a 5120 x 2880 (2560 x 1440 HiDPI) mode but I couldn't get it working under Mavericks. I'm not sure if I was limited by the OS or if Sharp's EDID-specified max resolution of 3840 x 2160 prevented OS X from accepting what I was trying to do.

A 1080p HiDPI mode is what I initially referenced...apparently this author doesn't think that works well. Don't entirely understand what he is describing about the low point density - I would think while the UI elements and text may be larger than a native 2560 x 1440 display, it would still be incredibly sharp and more visually appealing in comparison.

I am disappointed that Apple didn’t enable any HiDPI modes on the 32” Sharp display. While I found 3840 x 2160 a great resolution for video work, for everything else it made on-screen menus and text a bit too small. I would love to see a 2560 x 1440 HiDPI option (rendering offscreen at 5120 x 2880 and but scaling down to 3840 x 2160 for display) but it looks like I may have to wait for Apple’s own display before I get something like that.

Sounds like OSX doesn't have Retina 4k support yet. A 2560 x 1440 HiDPI option would make the UI sizing the same as the current models, but I don't really understand how that would work.
 
There was an article on this topic a month ago - https://www.macrumors.com/2013/12/3...e-the-wild-west-some-4k-monitors-unsupported/




A 1080p HiDPI mode is what I initially referenced...apparently this author doesn't think that works well. Don't entirely understand what he is describing about the low point density - I would think while the UI elements and text may be larger than a native 2560 x 1440 display, it would still be incredibly sharp and more visually appealing in comparison.



Sounds like OSX doesn't have Retina 4k support yet. A 2560 x 1440 HiDPI option would make the UI sizing the same as the current models, but I don't really understand how that would work.

From my understanding of how it works, if the video card doesn't support the resolution, it can't be done. So, for example, right now there would be no way for Apple to make a 4k iMac that had a 1440p HiDPI mode because the video cards don't support 5120x2880. Of course it might be possible that they could have custom chips made that supported it just for the purpose of having 1440p HiDPI.

Edit: Nevermind. I just found another forum with a person saying they're using 5120x2880 with SwitchResX, so I'm wrong. In that case it would just be the OS needs an update to support HiDPI modes on internal and external displays.
 
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From my understanding of how it works, if the video card doesn't support the resolution, it can't be done. So, for example, right now there would be no way for Apple to make a 4k iMac that had a 1440p HiDPI mode because the video cards don't support 5120x2880. Of course it might be possible that they could have custom chips made that supported it just for the purpose of having 1440p HiDPI.
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The problem is getting a video card that is as fast for 5120x2880 as the current ones are for 2560x1440. Without that speed the 5120x2880 screen would be useless for what I use my iMac for.
 
From my understanding of how it works, if the video card doesn't support the resolution, it can't be done. So, for example, right now there would be no way for Apple to make a 4k iMac that had a 1440p HiDPI mode because the video cards don't support 5120x2880. Of course it might be possible that they could have custom chips made that supported it just for the purpose of having 1440p HiDPI.

Edit: Nevermind. I just found another forum with a person saying they're using 5120x2880 with SwitchResX, so I'm wrong.

Interesting. So are they able to run a 2560x1440 HiDPI mode?

Here is a guy that setup a 4k monitor and running at 1080p HiDPI mode:

https://www.youtube.com/watch?feature=player_detailpage&v=pyqtyVx_j_o#t=285

Since it isn't yet natively supported I'm not sure if looks as good App and system wide as the macbook retinas.

I'm just curious how Apple will actually natively support 'Retina' scaling on 4k displays. I think it's clear they won't actually have a native 5120x2880 display forthcoming.

IMO, 1080p HiDPI (Retina) seems to be the what Apple will do for the Thunderbolt Display, 27 inch iMac AND the 21.5 inch iMac. It doesn't seem that bad unless you really need the extra screen real estate, in which case you could put it into a higher resolution mode that isn't retina scaled, just like the MacBook retinas.
 
Interesting. So are they able to run a 2560x1440 HiDPI mode?

Here is a guy that setup a 4k monitor and running at 1080p HiDPI mode:

https://www.youtube.com/watch?feature=player_detailpage&v=pyqtyVx_j_o#t=285

Since it isn't yet natively supported I'm not sure if looks as good App and system wide as the macbook retinas.

I'm just curious how Apple will actually natively support 'Retina' scaling on 4k displays. I think it's clear they won't actually have a native 5120x2880 display forthcoming.

IMO, 1080p HiDPI (Retina) seems to be the what Apple will do for the Thunderbolt Display, 27 inch iMac AND the 21.5 inch iMac. It doesn't seem that bad unless you really need the extra screen real estate, in which case you could put it into a higher resolution mode that isn't retina scaled, just like the MacBook retinas.

I also suspect that Apple will use 4k for all of the iMacs and the Thunderbolt Display. Personally, I find the UI to be too small at 1440p. I'd prefer to use it at 2048x1152 HiDPI. With a 4k iMac, it would be great because you could choose your preferred space, just like on the MacBooks. Need high res, use 2160p. Want the full Retina display, use 1080p HiDPI.
 
I think they'll offer 1080 hidpi retina mode,
but also they should offer the modes from the rmbp that offer different scaling sizes of the UI basically.

I NEED the screen real estate of the 1440 resolution for after effects, would even wanna have more definitely! It can't be so hard to implement that on the other macs. It's already there right in the rmbps.. I tried it out at the weekend and I thought it look absolutely brilliant in all of the modes, even the non native ones like 1080 on the macbook!
 
What Apple needs to do first is making OSX truly HiDPI-perfect and resolution independent. Not the 2x scaling method they're using now. Currently, you can only select 1 "retina"-resolution in OSX' scaling. Choose anything else and you'll see interfaces, icon's and text become less sharp than the so called "retina"-scale. It really blows my mind even text becomes fuzzy if the Retina-scale is not chosen!

The scaling should work just as the scaling-method for the Dock: fluently and sharp, independent of chosen size. Then, and only then, Apple can come with their retina-lineup of iMacs and display's.

"Why" you say? Well as the TS stated it's fairly simple for the 21.5" iMac: with a resolution of 1920x1080 it's Retina resolution would be a 4K display. Brilliant match! But for the 27" iMac or Thunderbolt Display... 2x the existing resolution of 2560x1440 gives a strange, meaningless, hard-to-drive and even more expensive to build 5120x2880 resolution. Reasons enough to NOT opt for this 5120x2880 resolution and enough reasons to be 4K:

  • Content (Movies, games) at 1920x1080 would still be pixel-sharp since 4 physical pixels of the 4K-display can act as 1 pixel and act as native 1920x1080.
  • 1920x1080 is still currently the most dominant resolution, opting for 4K eases the transition (see first point)
  • A lot of Mac Pro-users are video editors, who really want/need a 4K-display for 4K video
  • 4K displays are already being made while prices drop, which makes it easier and cheaper for Apple to use those instead of developing some other resolution
  • The more devices use 1 resolution (4K), the easier for developers
  • Go higher than 4K and it's even more difficult to drive and find appropriate GPU's
  • Is it really necessary to go higher than 4K on a 27" display? Or is it only to be able to call it "Retina"?

The list can be even longer, but the only argument I could find for the 27" displays (iMac or Thunderbolt display) to be 5120x2880 is to put the current resolution into Retina. But that's not the real problem: Make OSX truly HiDPI-capable as I explained above and every Apple computer/display would benefit from it since users will be able to choose their own preferred scale.
 
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