If you draw on paper and need to storyboard a film in 2:1 format, this free PDF storyboard template is for you.
This template has two DIN A4 horizontal sheets with nine frames per page, in 2.00:1 (Univisium) aspect ratio, ready to use, awaiting your drawings.
You can print it out and start drawing on paper. Another way you can use this template: open it in Photoshop, choose crop to Art Box or Crop Box in Import PDF > Page options and draw your board on a new blank layer.
You can get an editable version of this template for Procreate here: https://storyboards.gumroad.com/l/prcrt_stb_2x1.
There is also a desktop publishing version of this template for InDesign, with much more variations and choices available here: https://storyboards.gumroad.com/l/2x1_A4_InDsgn_hrztl.