Choosing the best banner width for your reel
The banner image is the most dynamic image in the reel template and will resize based on how wide the browser window is (up to the width of the banner image). Since you cannot predict how wide a recipient's monitor is, it's best to design with a wider window in mind. The width of your image file can make a big difference in the visual experience for the recipient.
Recommended width: at least 2400px (for full width on average desktop monitors)
Minimum recommended width: 1100px wide (otherwise, the banner may appear more narrow than the rest of the reel)
Comparing banner widths - 2400px, 1100px, and 900px
In the video examples below, all three banners appear the same size when viewed in a narrow browser window (i.e., tablet or mobile). But when the windows are stretched wider, the 2400px image is much more flexible. Please keep in mind, as a banner resizes to fit a larger width, it will also increase in height. If you want to keep your artwork from becoming very large across the top of your reel you can try reducing the height of your image file.
These screen captures were taken on a 16" retina screen and the banner height was sized down proportionately as width decreased.
2400px wide x 150px tall banner
As you can see, this banner stretches across the reel at all browser sizes. Granted, if the viewer has an ultra-wide monitor and likes to open their browser window the full width, then even this banner will eventually have white on the left and right sides.
1100px wide x 69px tall banner
The 1100px banner does not stretch wider than the content of the reel. This is our minimum recommended width since the banner will align with the rest of the reel, even if it doesn't stretch across from edge to edge.
900px wide x 56px tall banner
Finally, the 900px wide banner will almost always appear shorter than the reel content unless being viewed on tablet and mobile. If this is not the visual effect you desire, you may want to resize your banners to at least 1100px wide.