OPAL v1.0.0 Changelog:

Lighting, Textures, Foliage and Blur:

added "Vanilla Side Shading Intensity" option [affects block and entity sides]
added "Vanilla Corner Shading Intensity" option [affects corners between blocks]
greatly decreased Vanilla shading intensity [both side and corner]
lava is no longer affected by vanilla shading
slightly decreased regular lava brightness
slightly increased nether lava brightness
slightly decreased Ambient Occlusion strength
expanded "Ambient Occlusion Strength" option slider
blocklights are now less visible in the sunlight
improved emissive textures of Magma Cubes, Nether Portals, Torches and Endrods
decreased sand blocks brightness
improved foliage lighting and brightness
Weeping Vines are now slightly brighter
Twisting Vines are now less affected by the wind
improved all block waving strength option sliders
added new "Distant" mode for Depth of Field option

improved morning/evening colors and color transitions
overhauled night colors
moon light brightness is now affected by moon phases
added "Moon Phases" option
added sliders to control moon light brightness for each moon phase
sun and moon will now hide under the horizon
improved skybox sun and moon colors and brightness transitions
renamed "Skybox Brightness Transition" option to "Skybox Color Transition"
improved horizon sky fog during mornings/evenings
slightly reduced sunlight-colored fog in the mornings/evenings
added "Ground Fog" option
added dynamic ground fog [density builds up at night and decreases in the morning]
added "Ground Fog Density" option
increased cloud view distance during clear weather
improved cloud colors and brightness during day/night
greatly improved cloud color and brightness transitions during mornings/evenings
improved brightness transition between bright and dark areas
slightly improved Magma Block and Sulk Sensors blocklights
expanded "Light Shaft Strength" option slider
increased light shaft strength during sandstorms
added "Sandstorm Dusty Light Shafts" option
light shafts are now dusty during sandstorms [this feature works only on Iris]
improved sandstorm colors

overhauled colors and brightness for each Nether biome
added "Nether Fog Mode" option
Nether fog is now advanced [biome fog + lava fog; multiple density gradients]
increased view distance in the Nether thanks to the new fog mode
"Per Biome Weather" option no longer affects Nether
added "Per Biome Nether" option
biome fog density now changes depending on a Nether biome
added options to change fog density of every Nether biome
added option to change Nether lava fog density
added options to change lava and biome fog intensities
added options to change lava fog colors
color and brightness transitions are now less visible while crossing biome borders
"Windy Caves" and "Dynamic Wind" options no longer affect Nether
added "Nether Wind Waving Strength" option
Nether is now slightly windy
added options to change blocklight color only in the Nether
added options to change bloom only in the Nether
added options to change chromatic aberration only in the Nether