How do I save a black & white picture to a 1-bit image file?

I need a 1-bit image file to print on a laser engraver. I used to have quite a few graphics applications that could save 1-bit black & white TIFF files. I've owned Macs since 1987. However most of my old apps won't run on current MacOS versions and I just discovered that my current graphics apps (Affinity Photo, Affinity Designer, Acorn, Pixelmator, Pixelmator Pro) won't save 1-bit files. 8-bit grayscale is as close as they get. I have no problem editing an image so that it only contains black or white pixels. Pixelmator Pro's **Format: Effects: Halftone: Dot Screen** or **Line Screen** effects are great for what I want. It's the underlying file format that I'm having problems getting to with modern software. I have a workaround. I can save an 8-bit TIFF to a USB thumb drive and open it in Microsoft Paint on the Windows PC attached to the laser cutter and save it as a 1-bit BMP or TIFF file for the laser cutter's software. However the grey haired Mac nerd in me is offended that Windows still has a feature that seems to have vanished from current Mac systems. Does anyone have suggestions for an app to convert grayscale images to 1-bit TIFF files?