Methanol (one carbon alcohol - 'wood' alcohol) will burn mostly blue when burning with enough air (oxygen). Ethanol (two carbon 'drinking' alcohol) will burn blue but with less air mixing in will not burn as cleanly and with more carbon will produce some soot, which 'burns' orange.
In a taller glass with the alcohol level further below the rim, there will be not as good air mixing and a more of an orange flame. Also with more rapid evaporation of the alcohol, especially after it heats up, there will be more alcohol vapors produced so air mixing may not be sufficient to burn as cleanly,. Higher alcohol vapor to air ratio burns more orange.

Gently pour in the alcohol to help it not mix in. Can also try gently heated alcohol for increased vapor evaporation rate, but careful not to ignite it.

Good photos. Be careful.