Improve doc to state when tilt is vs wavelength #278

Job	Run time
Tests on paywalled platforms	0s
Tox test (py38)	1m 44s
Tests on other platforms (windows-2019, 3.10)	3m 48s
Tox test (py39)	1m 52s
Tests on other platforms (windows-2022, 3.11)	2m 29s
Tox test (py310)	1m 45s
Tests on other platforms (windows-2022, 3.12)	2m 32s
Tox test (py311)	1m 51s
Tests on other platforms (macos-12, 3.11)	1m 28s
Tox test (py312-cover)	2m 45s
Tests on other platforms (macos-13, 3.12)	1m 42s
Tox test (docs, graphviz)	2m 4s
PyPI packaging	0s
Docker image	0s
	24m 0s

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