I am still testing this but it fits my Cut sheet film holders. Easy to read "X" side means no image on that side. "O" is the side an image will be exposed.

Estimated image size 92mm x 246mm (3.6" x 9.7")

With an Aspect Ratio of 2.69:1

The gap is a little over 5mm from each image

How to use:

1. COMPOSITION
2. Insert your film holder
3. Remove OEM dark slide
4. Insert the HF810 dark slide "O" means Go "X" means No go
5. Make your exposure
6. Remove the HF810 dark slide
7. Insert your OEM dark slide
8. Repeat the above steps with the HF810 in the opposite orientation

Best to print with a layer height of 0.1 or 0.2