I ran across this question today from someone who says that he does not print that many of his images or do anything specific with them, but he would like to just simply be able to view them at maximum size, on a plain black background with no formatting or overlays of any sort.
The question is really quite valid because the emphasis in Lightroom is on doing something with the individual modules not doing nothing. Default settings in Lightroom tend to add a fair number of adjustments that are not always wanted.
There may be other ways of getting to this minimalist end but here is my version.
1. In the Library module I select what images I want to view, I click on the images and type B to make a Quick Collection of those images.
2. I click on the Quick Collection button in the Library panel, which makes only Quick Collection visible.
3. I click on the Slideshow module selector and bring the Quick Collection into the Slideshow module.
4. In the Slideshow module, I turn off and deselect almost all the options. Stroke Border, Cast Shadow, Show Guides (set all to 0 px), Identity Plate, Rating Stars, Text Overlays, Color Wash, turn off Background Color (or set to black), no Soundtrack and turn off Slide Duration.
5. Individual settings can be applied to the images if you wish, but it is best to start with a clean plate.
6. Add a template to the Template Browser (the Add button is below the Template Browser) - I call this zero settings template “Black Out”.
7. Press on Play and press your right arrow key for advancing the individual images at maximum size, on a pure black background.
8. To fill your entire screen you can select Zoom to Fill Frame in the Options but that will crop into images, unless they are already cropped for your screen.
That is it, once you have set up the parameters in the Slideshow module, it is a simple matter of selecting as many images as you like, opening the Slideshow module, selecting the “Black Out” preset and pressing the Play button.