12L 17s

↖11L 16s	↑12L 16s	13L 16s↗
←11L 17s	12L 17s	13L 17s→
↙11L 18s	↓12L 18s	13L 18s↘

Brightest mode	LsLsLssLsLssLsLsLssLsLssLsLss
Period	2/1
Range for bright generator	12\29 (496.6¢) to 5\12 (500¢)
Range for dark generator	7\12 (700¢) to 17\29 (703.4¢)
Parent MOS	12L 5s
Sister MOS	17L 12s
Daughter MOSes	29L 12s, 12L 29s
Equal tunings
Supersoft (L:s = 4:3)	41\99 (497¢)
Soft (L:s = 3:2)	29\70 (497.1¢)
Semisoft (L:s = 5:3)	46\111 (497.3¢)
Basic (L:s = 2:1)	17\41 (497.6¢)
Semihard (L:s = 5:2)	39\94 (497.9¢)
Hard (L:s = 3:1)	22\53 (498.1¢)
Superhard (L:s = 4:1)	27\65 (498.5¢)

The 12L 17s MOS scale splits the small steps 1-1-2-1-2-1-1-2-1-2-1-2 between the large steps. Its chroma-positive generator is a near-perfect fourth of no more than 5\12 (500 ¢), and 53edo falls near the beginning of its boundary of "practicality" and its harmonic entropy minimum of exactly 4/3.

Scale tree

12/29					496.552
				53/128	496.875
			41/99		496.97
				70/169	497.041
		29/70			497.143
					497.211
				75/181	497.238
					497.254
			46/111		497.297
					497.353
				63/152	497.368
	17/41				497.561
				56/135	497.778
			39/94		497.842
					497.935
				61/147	497.959
					497.985
		22/53			498.113
					498.178
				49/118	498.305
			27/65		498.4615
				32/77	498.701
5/12					500