It's stylized, just like the oversized windows and so on. It doesn't have to be red, Golly has posted a bunch of Ruski ships with green bottom paint and I've posted a few with black. However, most navies uses red bottom paint, but finding out the exact shade is pretty much impossible in many cases so we just go for a basic red.
As for drawing programs, technically, all you need is MS Paint, though personally I prefer
Paint.NET since it has layer support and a bunch of other nice features. The only drawback I've run into so far is that it can't handle truly massive pictures.
I had a hard time trying to resize the blueprints of the Willemoes, since they were some 37 thousand pixels wide and half again as long.
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“Close” only counts with horseshoes, hand grenades, and tactical nuclear weapons.
That which does not kill me has made a grave tactical error
Worklist
Source Materiel is always welcome.