Problem with scaled resolutions not available on external 4k monitor?

[sittingstill]

Hi - does anyone know why "retina mode" scaled resolutions might not be available over HDMI? I am using a 15" 2015 Macbook Pro with Retina Display, and for the last few years I have been using various 43" 4k tv's as secondary monitors for a particular work requirement, running them at a 'looks like 1440p' scaled resolution, which is perfect. I recently bought a new tv, as a location change necessitated me having something smaller, but when I connect it to my Macbook Pro via HDMI, the Retina mode / scaled resolution slider is not available...the only options I get are:

"3840x2160 (low resolution)"
"1080p" nb: this is actually 1080p, not a scaled 'looks like 1080p', thus looks terrible (and the 2 others - see screenshot below)

Option clicking simply provides a few extra non-native, non scaled resolutions. To make matters worse, the '3840x2160 (low resolution)' option, in addition to being too small, isn't even just native 2160p, its some kind of fuzzy "low resolution" thing, suggesting there is an issue somewhere.

Could anyone point me in the direction of what might be causing this problem? I have tried using a few different HDMI cables, just to see if there was an issue (all the HDMI cables work when connecting the Macbook to the old 4k tv and a 4k monitor). I can't find anything about this specific problem - I can send the TV back for a full refund and buy a new one, no problem, but I would be hesitant to buy a new one before understanding if there is some kind of variable in specs I am unaware of that causes this problem. Thanks!

 

[AdamA9]

I had a similar issue with my 4k monitor, I had to reset the monitor settings and then I saw the retina options for the monitor itself.

 

[Fishrrman]

Some thoughts:

The "30hz" looks to be a warning. Shouldn't you be getting 60hz?

Does the new tv have HDMI 2.0, or not?

If so, are you using the specific HDMI 2.0 port? (many tvs have more than one HDMI port, but only one may be HDMI 2.0)

See this page for MacBook compatibility with 4k displays:
https://support.apple.com/en-us/HT206587

Are you using a displayport-to-HDMI 2.0 adapter (the "2.0" is very important)?
Are you using a high-speed HDMI cable between the adapter and the tv (again, not all HDMI cables are equal)?

 

[sittingstill]

I had a similar issue with my 4k monitor, I had to reset the monitor settings and then I saw the retina options for the monitor itself.

Hey Adam, how do you "reset the monitor settings", or more specifically, what kind of monitor seetings are you resetting, parameters etc?
[doublepost=1530554021][/doublepost]

Some thoughts:

The "30hz" looks to be a warning. Shouldn't you be getting 60hz?

Does the new tv have HDMI 2.0, or not?

If so, are you using the specific HDMI 2.0 port? (many tvs have more than one HDMI port, but only one may be HDMI 2.0)

See this page for MacBook compatibility with 4k displays:
https://support.apple.com/en-us/HT206587

Are you using a displayport-to-HDMI 2.0 adapter (the "2.0" is very important)?
Are you using a high-speed HDMI cable between the adapter and the tv (again, not all HDMI cables are equal)?

I am pretty sure the 30hz is not a warning....HDMI 2.0/displayport isn't part of the equation, as I am using a 2015 Retina MBP (not HDMI 2.0) which produces 2160p at 30hz over HDMI 1.4. The variable is not the compatibility, the variable is why it worked for 2 years and now doesn't work

 

[cobracnvt]

You may also want to look into the deeper settings on the TV, to see why you're not getting 60 Hz. Is there a PC Monitor mode setting on the TV? Is HDR and UHD turned on, etc. Is there a certain port on the TV to use? On some Samsung TVs, you have to name the input "PC" to put it in computer monitor mode.

 

[sittingstill]

You may also want to look into the deeper settings on the TV, to see why you're not getting 60 Hz. Is there a PC Monitor mode setting on the TV? Is HDR and UHD turned on, etc. Is there a certain port on the TV to use? On some Samsung TVs, you have to name the input "PC" to put it in computer monitor mode.

I am NOT trying to get 60hz. The Macbook I have only produces 4k at 30hz via HDMI, which is fine for the application I am using it for. 60hz is not part of the equation....I only need 30hz

 

[cobracnvt]

The modes do more than just the HZ, it makes the picture appear better as well. I went through a few 40"+ 4k TVs last year trying to use them as a monitor and I wound up returning them because it would really hurt my eyes after a while.

This page has a good write up on it http://www.geeks3d.com/20141203/how...-chroma-subsampling-used-with-your-4k-uhd-tv/

 

[sittingstill]

The modes do more than just the HZ, it makes the picture appear better as well. I went through a few 40"+ 4k TVs last year trying to use them as a monitor and I wound up returning them because it would really hurt my eyes after a while.

This page has a good write up on it http://www.geeks3d.com/20141203/how...-chroma-subsampling-used-with-your-4k-uhd-tv/

Sure sure, I know. My query was in regards to scaled "retina modes" not being available when connect to a 4k display via HDMI, on a machine it had previously worked from....the increased colur gamut and frame rate of HDMI 2.0 isn't part of the equation

 

[cobracnvt]

Sorry, I guess I was going off topic...

Based on this page: https://support.apple.com/en-us/HT202471 Have you tried holding down the option button to see more resolution options?

 

[AdamA9]

Hey Adam, how do you "reset the monitor settings", or more specifically, what kind of monitor seetings are you resetting, parameters etc?
[doublepost=1530554021][/doublepost]

I am pretty sure the 30hz is not a warning....HDMI 2.0/displayport isn't part of the equation, as I am using a 2015 Retina MBP (not HDMI 2.0) which produces 2160p at 30hz over HDMI 1.4. The variable is not the compatibility, the variable is why it worked for 2 years and now doesn't work

I went into the monitor settings itself via the buttons on the back of it and reset all monitor settings. The scaled for retina options then appeared on my mac display settings to allow me to set it up.

If I go back now, I cannot see these options unless I reset my monitor again. I have an LG IPS 4K monitor.