Serial Digital

The common advice when creating a PowerPoint presentation at a custom resolution is to enter the aspect ratio in the page setup box – for instance, 16in x 9in to create a 16:9 presentation, or 30in x 15in to create a 30:15 ratio presentation.

But how does the ratio relate to the resolution? You can create a 16:9 PowerPoint presentation, but output that presentation at 1920×1080 or 1280×720 (both 16:9 ratio resolutions).

Well PowerPoint will automatically scale a presentation’s slides to match the output resolution of the display – this includes letterboxing or pillarboxing to convert the aspect ratio to the output resolution (e.g. you can output a 16:9 PowerPoint presentation at a resolution of 1024×768 (4:3 ratio) and the presentation will appear letterboxed – with black bars top and bottom).

What this means is that you will need to ensure your source images and content is suitable for being scaled to the resolution that you wish to output at – for instance, if you want to insert a photograph that will consume half of the width of a slide, and you want to output your slides at 1920×1080 resolution, then you will need to ensure your photograph is at least 540 pixels in width, or else quality will be compromised.

Interestingly, though, you can use page sizes to give yourself some more screen real-estate when designing slides – for instance, if you create a presentation that is 16 in by 9 in, and insert a photograph, the photo might take up the entire slide, and you will need to size it down to fit anything else on the slide – whereas if you create a presentation with dimensions of 160 in by 90 in, and insert the same photo, it’s likely to consume only a small percentage of the slide – you can then size it up, or use the space to add other elements to the slide.

Regardless of the page size, remember that so long as your source image is at least the same resolution as your output screen resolution, the image will show up without any loss in quality.