A lot of the first half of the Ichabod segment was based on the color relations of pink/magenta and green/turquoise. Since this was the comedy half, the lighting was secondary and we were looking mostly at object colors with only occasionally a shadow to indicate special lighting (dawn or candle light).
However, as the story progresses towards Halloween and night time, it becomes more dramatic and colored lighting is emphasized.
Dark and gloomy sets are nothing new or extraordinary for Halloween scenes. So it’s more the subtle (and not-so-subtle) use of (painted) colored light that is interesting here.
As if influenced by the outside lighting, the atmosphere inside the barn changes from diffuse high key (without cast shadows) to harsher low key lighting as Brom performs his Halloween stories.
So far all the colored light originated from within the barn (candles, fireplace, spitting fire). The forest on the other hand is lit much more expressionistic and mainly based on blue and green which is fairly common for night-time depictions of forests.
What I like about these backgrounds is how blue and green light is used to illuminate tree trunks to add a layer of contrast that couldn’t be achieved by staying within the values of blue alone. One could argue that the blue light is caused by the moon but the inclusion of it in the early graveyard shot does not support this notion. And besides, where does the green light come from then? The leafs flying by are dark brown, so they subtly stand out in front of the trees even if they are not very different in value.
|The visual illusion reminiscent of Snow White is unmasked by a slight change of moonlight.|
In more atmospheric moments (above) the pictures are composed around value contrasts with more subtle shades of blue next to each other. Moments of tension (below) on the other hand are emphasized by clearer contrasts of hues.
|right: what a great pose!|
|green lit characters against a purple background turning up later in the villain song of The Princess and the Frog.|
The effect of double exposing backgrounds in different colors is only used very economically. Wherever it was possible, the same effect is achieved by single backgrounds that are not seen in their entirety under the camera.
Here (below) for example, the purple part is emphasized as the camera moves away from the image coinciding with the character blocking out the blue part of the background. In motion it looks as if the lighting turns to purple while the horseman is approaching.
|the green doesn't turn red in this final clash which is more comical than dramatic.|
Note how different this romantic depiction of the bridge is from the village we have seen in the beginning of the segment. So while the backgrounds of the comedy half of the picture were much more stylized, the scary second part relies on the common romantic 19th century illustration style associated with gothic horror stories.
There are a few color keys and inspirational sketches by Mary Blair and her collaborators online. It's interesting that they hardly reflect the production color palettes. But since I don't know anything about the film's production process I just paste them here for you to look at.