A painting of a man writing a letter in front of a hot air balloon

An medieval engineer drawing a plan of a hot air baloon on paper, an old medieval man weaing glasses drawing the plans of a (hot air baloon: 1.5) the lines in the plan are the hot air baloon to exteme details, it is painted paper, with pencil, medival study room background, high details, best quality, 16k, [ultra detailed], masterpiece, best quality, (ultra detailed), full body, ultra wide shot, photorealism 3d rendering 3DMM