I've just bought a new LG 27UL500 monitor. I want to use it with my Late 2014 iMac to extend the work area when video editing. However when connecting it via thunderbolt to the HDMI input of the monitor, it will only work when the screen mirroring option is selected. When I try to use the screen extension mode the monitor goes blank and stays blank, even though it shows up in the display dialogue box in my iMac settings as LG HDR 4K. Shifting the arrangement of the monitors in the dialogue box does nothing. I tried Command-F1 and that also achieved nothing.
I also noticed that the highest setting I can switch to is 1080p even though the external monitor is 4K.
I plugged in my 2015 Macbook Air running Sierra and it worked perfectly, switching automatically to screen extension mode.
I'm sure the problem is that I'm running Yosemite on my iMac. The reason I haven't upgraded the operating system is because it will only allow me to upgrade to High Sierra. And if I upgrade to High Sierra then Adobe After Effects CS6 will not work! I can't afford the £50 per month ($70) Adobe charges per month for Creative cloud CC, but I purchased the monitor specifically for Adobe After Effects work.
In the past I tried downloading the Sierra operating system and installing that, but encountered repeated loading errors on my iMac and had to return to Yosemite.
Is there any patch or fix for this?
I also noticed that the highest setting I can switch to is 1080p even though the external monitor is 4K.
I plugged in my 2015 Macbook Air running Sierra and it worked perfectly, switching automatically to screen extension mode.
I'm sure the problem is that I'm running Yosemite on my iMac. The reason I haven't upgraded the operating system is because it will only allow me to upgrade to High Sierra. And if I upgrade to High Sierra then Adobe After Effects CS6 will not work! I can't afford the £50 per month ($70) Adobe charges per month for Creative cloud CC, but I purchased the monitor specifically for Adobe After Effects work.
In the past I tried downloading the Sierra operating system and installing that, but encountered repeated loading errors on my iMac and had to return to Yosemite.
Is there any patch or fix for this?