How to Add iPhoneX Launch Image

Using Xcode Version 9.0 (9A235), I am trying to add a Launch Image for iPhoneX at the requested 2436px × 1125px (landscape). Currently I am using a Storyboard and it looks like this:

'launchimage' is an Image View linked to an Image Set:

And the Image Set is as follows:

The only place I get an iPhoneX sized image is in a Launch Image set:

But when I try to select a Launch Image in the Image View on the storyboard it can't be selected:

Any help on how to add the correct sized launch image for iPhoneX or is it back to Launch Images? I would prefer the correct sized image, not a stretched one.

UPDATE:

I would like to explain why I want the image to be exactly the same pixel per pixel. Following the Guidelines in https://developer.apple.com/ios/human-interface-guidelines/icons-and-images/launch-screen/ my launch image is a static version of the first page of the App. If the Launch Image is stretched then there is a noticeable switch from Launch Image to First Page. Which sort of defeats the object of the guidelines. Apple recommend using a storyboard launch, but it seems you can't follow their guidelines if you do. Typical, really.

If your used the LaunchImage.launchimage for Launch, the solution is (in Xcdoe 9.0):

1. Select Assets.xcassets, right click on middle pane, select App Icons & launch Images -> New iOS Launch Image . Then move the old LaunchImage.launchimage images to the new one, and add the image size with 1125×2436 px for the iPhoneX.

2. Also, you can add the following json object to Contents.json file which on LaunchImage.launchimage folder in your old project。Once Xcode refreshes, just drop in a 1125×2436px image. If you need landscape, you can add another with the orientation.

	{
      "extent" : "full-screen",
      "idiom" : "iphone",
      "subtype" : "2436h",
      "minimum-system-version" : "11.0",
      "orientation" : "portrait",
      "scale" : "3x"
    }

To the 2018 lazy devs like me who has an existing project that has an old version of launchimage (with no iPhoneX variant), here's my solution to support iPhone X - this is a shortcut one for you.

1. Open Assets.xcassets in your Xcode.
2. Right click in your LanchImage then select Show In Finder.
3. Open the Contents.json
4. Paste the follow codes inside your "images" array.

 {
  "extent" : "full-screen",
  "idiom" : "iphone",
  "subtype" : "2436h",
  "filename" : "ipxportrait.png",
  "minimum-system-version" : "11.0",
  "orientation" : "portrait",
  "scale" : "3x"
},
{
  "extent" : "full-screen",
  "idiom" : "iphone",
  "subtype" : "2436h",
  "filename" : "ipxlandscape.png",
  "minimum-system-version" : "11.0",
  "orientation" : "landscape",
  "scale" : "3x"
},

Replace of course the filename with appropriate images. Voila!