Transition based off day length speed? ( day/night system)

This is what I came up with. Sorry if it's a bit huge, but I thought it might be useful to make it decent. I tested it and it seems to work fine. Let me know if it doesn't work correctly.

 using UnityEngine;
 using System.Collections;
 using System;

 public class TimeOfDay : MonoBehaviour
 {
    public float timePerDay = 1140.0f; // In seconds
    public float sunrise = 6.0f; // In hours
    public float sunset = 17.0f; // In hours
    public float hoursPerDay = 24.0f; // In hours

    public Color dayAmbientColor;
    public Color dayBackgroundColor;
    public Color nightAmbientColor;
    public Color nightBackgroundColor;

    public float currentTime = 0.0f;

    private float NightDuration
    {
        get { return timePerDay - RelativeSunset + RelativeSunrise; }
    }

    private float DayDuration
    {
        get { return RelativeSunset - RelativeSunrise; }
    }

    private float RelativeSunrise
    {
        get { return timePerDay * (sunrise / hoursPerDay); }
    }

    private float RelativeSunset
    {
        get { return timePerDay * (sunset / hoursPerDay); }
    }

    private float Midday
    {
        get { return (DayDuration * 0.5f) + RelativeSunrise; }
    }

    private float Midnight
    {
        get { return Mathf.PingPong((NightDuration * 0.5f) + RelativeSunset, timePerDay); }
    }

    // Use this for initialization
    public void Start ()
    {
 
    }
 
    // Update is called once per frame
    public void Update ()
    {
       currentTime += Time.deltaTime;

       // If we have reached the end of day start the cycle over
       if (currentTime >= timePerDay)
           currentTime = currentTime - timePerDay; // Keep the extra time

       Color currentAmbientColor = Color.black;
       Color currentBackgroundColor = Color.black;

       float midday = Midday;
       float midnight = Midnight;
       float sampleTime = 0.0f;

       float minutesPastMidnight = (currentTime > midnight && currentTime < timePerDay) ? timePerDay - currentTime : timePerDay - midnight + currentTime;
       if (currentTime > midday && currentTime <= midnight)
       {
           sampleTime = (currentTime - midday) / DayDuration;
           Debug.Log("Sample Day: " + sampleTime);
       }
       else if (minutesPastMidnight >= 0)
       {
           sampleTime = 1.0f - (minutesPastMidnight / NightDuration);
       }

       currentAmbientColor = Color.Lerp(dayAmbientColor, nightAmbientColor, sampleTime);
       currentBackgroundColor = Color.Lerp(dayBackgroundColor, nightBackgroundColor, sampleTime);

       RenderSettings.ambientLight = currentAmbientColor;
       Camera.main.backgroundColor = currentBackgroundColor;
    }
 }