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Drupal 8 - Image Media Type - Manage Display Tab

1. Navigate to Manage Display Tab

Go to the Manage Display tab of the entity that the View Mode will be applied to.

In this particular case, we're applying it to an Image media type located at Admin Menu > Structure > Media Types > Image > Manage Display.

Drupal 8 - Image Media Type - Select Original View Mode

2. Select View Mode

Scroll down the screen.

Click on the Custom Display Settings vertical tab to open it.

Select the desired View Mode - in this case it's the Original view mode.

Click the Save button.

Drupal 8 - View Modes - Original Image View Mode - Enabled

3. View Mode Enabled

Looking up at the top of the screen, you'll now see some tabs added. One will be named Default and the other will be the name of the View Mode you just enabled - in this case, Original.