The evening shots where done in blue. These were day for night (since they couldn't shoot at night in 1958 and capture all the detail) otherwise these shots would have had to be done on a soundstage. Instead they shot during the day and put the blue filters over the lens to create the illusion of night. The filters (according to the cameraman who told us this at a party one night, the filters were mostly used to hide the weather, rain and day for night shots.)
My guess is they knew the weather was causing production delays and costing money. Using a filter would hide the gray. The studio tech processing guys over staurated the color (Maybe the studio liked it, Logan didn;t and asked they be toned down. He was told it would take 6 months to de process the color and the opening was a reserved seat attraction and could not be moved since sales were already in place.
Actually some of the filters do put you into a trance and then we're back to reality, So they aren't so bad and sometines quite good
"Carousel" had been shot on location at night in 1955 and the footage was deemed unusable due to the lighting etc. Those scenes were re-shot on a Sound stage (you can notice a distinct difference)