I replaced the 5mm LED with a set of 3mm LEDs to provide a little bit of extra resolution. I've reduced light pollution a bit too by painting the bottom of the LEDs and some of the topmost surfaces of PCBs, stages.
Which makes some fun patterns
And a triforce once I realised I needed to set the stepper speeds individually for each coordinate (so they arrived at the same time). The photo on the left is the same set of triforce coords, prior to this change.
At the moment I'm using Excel to manually set up a set of coordinates, it's slow but it does work!
This is heaps of fun to play around with. I'm going to come up with a few more patterns for this setup before doing anything else.
Some limitations are making themselves visible however and the pattern above is about the limit of what I can do. Not only is the resolution still pretty small, but it is also the extent of how long it can draw for. That pattern above takes exactly 15 seconds (max exposure length on my camera). I realised also that due to RAM limitations I won't be able to program more than 200 coordinates. For straight line drawings that's fine, but will make drawing curves difficult.