Judged by Tillman Kleinhans
Below are some guides for how to produce images for the mono section of the competition, if you are having trouble or would like another piece of software added to this list please ask
Snapseed
The first 2 mins of this video shows what you need to do to colorise your black and white image. Of course this example is green – you would need to combine the red and green curves to make orange.
Lightroom
Online converter
You can just us this online converter, but I’m not sure it will work with larger files
https://manytools.org/image/colorize-filter/
Photoshop
https://www.kristendukephotography.com/how-to-turn-images-to-one-color-photoshop-tip/
Affinity
You could try any of the suggestions on this forum post…