Old Lighting & Old Water v1.20_1 (for Minecraft 1.20) by Sencie
https://www.planetminecraft.com/texture-pack/old-lighting-amp-old-water/

The Ressource Pack brings back:
Old lighting (pre-Beta 1.8) Lighting is not colored but white
Old Water (pre-Beta 1.8) Classic texture, saturation and underwater fog
Old Lava (pre-1.5) Classic lava texture
Old Day Sky (pre-Beta 1.8) with temperature variation for biomes
Old Night Sky (pre-Beta 1.5) Stars are brighter, larger and no moon phases
Old Nether Fog (pre-1.13.1) The fog has a darker tint & no color variation for biomes
Old End Sky (Between 1.0.0 and 1.3.1) The sky is dark grey as it was when The End was released
Old Grass & Foliage (between Alpha 1.2 and Beta 1.7.3) Greener in forests and in cold biomes
Old Splash Texts (from Beta 1.7.3)

Also:
No air particles (pre-1.16)
No underwater particles (pre-Beta 1.8)
Mob eyes are not glowing (pre-1.15)
Ghast is glowing (pre-Beta 1.8)
Sugar cane uses old color (pre-1.7.2)

OPTIFINE REQUIRED www.optifine.net/downloads 
Make sure that Custom Color, Custom Sky and Emissive Textures are ON. 

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RECOMMENDATIONS FOR A CLASSIC EXPERIENCE:
-My other pack 'Old Sounds' https://www.planetminecraft.com/texture-pack/old-sounds-4911323/
-My add-on 'No Enchantment' (pack that removes enchantment glint & makes orbs silent and invisible as pre-1.0.0) https://www.planetminecraft.com/texture-pack/old-lighting-amp-old-water/
Programmer Art pack or another retro pack:
-Developer Art Classic https://www.planetminecraft.com/texture-pack/devart-classic/
-Golden Days https://www.planetminecraft.com/texture-pack/golden-days-beta-reversion-for-modern-minecraft/
-Simpler Times https://www.planetminecraft.com/texture-pack/the-og-minecraft/
Settings:
-FOV: 70
-Brightness: Moody
-Render Distance: 10 (normal) or less (short)
-Fog Start: 0.2
-Mipmap Levels: OFF
-Smooth Lighting: OFF (which is pre-Beta 1.3)
-Biome Blend: 3x3
-Attack Indicator: OFF
Deactivate spawn of Phantom, Wandering Trader and Patrol at world creation or by changing level.dat with NBTExplorer with https://sourceforge.net/projects/nbtexplorer.mirror/
Use Forge mods to restore the old gameplay experience: restore old Hud, remove sprint, customise fog distance, restore old damage tilt, allow mob spawning when sleeping etc... (Sorry the links I had are now outdated)

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Q&A:
How did you make this pack?
I worked with side-by-side screenshot comparisons using previous versions of Minecraft to get the best results.

Why is the Nether darker than normal Minecraft?
Pre-Beta 1.8 Nether was darker and more scary. If it is too dark for you, you can adjust the Brightness setting.

Is the water like pre-Beta 1.8 or pre-1.13 (pre-Aquatic Update) in the pack?
The water is the pre-Beta 1.8 water. However, the underwater fog used to be closer and blocks used to be very dark underwater. There is no way around it except changing the code.
If you want the water (between Beta 1.8 and 1.12.2). Just delete the files you don't need (including underwater.json) in the .zip file.

How do I get the Old Night Sky (between Beta 1.5 and 1.2.5)? I prefer when stars are less bright. 
It is included in the pack. Just delete night.png, and rename greystars.png as night.png to use it.

How can I get the sides of the grass block to not be affected by the biome temperature (pre-Beta 1.5)?
It is included in the pack. Go to assets\minecraft\models\block. Delete grass_block.json and rename grass_block_graphics_fast.json as grass_block.json

Can I use your pack for my own ressource pack?
Yes. Please credit me (Sencie) with a link to my pack in your description.

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CHANGELOG:
v1.20_1 (2023-06-19)
Updated to 1.20
Removed air particles:
cherry_leaves.json

v1.19_1 (2022-06-29)
Updated to 1.19.
Removed air particles:
falling_spore_blossom.json
spore_blossom_air.json 

v1.18_1 (2021-12-07)
Updated to 1.18.
Old Day Sky improved: Added 1.18 biomes.

v1.17_1 (2021-06-13)
Updated to 1.17.

v1.16_24 (2021-03-24)
Old Day Sky improved in temperate biomes.

v1.16_23 (2021-03-19)
Old Day Sky improved in warm biomes.
Added accurate rain color and thunderstorm color for warm biomes.

v1.16_22 (2021-03-17)
Old Water improved (the tint of underwater.png is improved)
Add-on 'No Enchantment' improved (enchanted bottle contains invisible orbs for consistency)

v1.16_21 (2021-03-13)
Old Grass & Foliage improved: Added old Grass Block particles (pre-Beta 1.8).

v1.16_20 (2021-03-11)
Old Lighting improved: Ghast is brighter (pre-Beta 1.8).

v1.16_19 (2021-03-08)
Old Day Sky improved (rain, snow and thunderstorm fog looks better when using Render Distance: Far)
Old Grass & Foliage improved (added grass_block_graphics_fast.json) This is the default side of grass blocks (pre-Beta 1.5). It is not affected by the biome temperature.
To use it, delete grass_block.json and rename grass_block_graphics_fast.json as grass_block.json

v1.16_18 (2021-03-04)
Old Grass & Foliage improved: Sugar cane uses old color (pre-1.7.2).

v1.16_17 (2021-03-03)
Added Old Day Sky (pre-Beta 1.8): 
Temperature variation for biomes.
Rain and thunderstorm have an accurate color.
Solved the Optifine glitch (sky is no longer too saturated when it rains).

v1.16_16 (2021-02-28)
Old Lighting improved: The eyes of Spider, Enderman, Phantom and Ender Dragon are less glowing (pre-1.15).

v1.16_15 (2021-02-19)
Old Night Sky improved: transition is smoother between day and night.

v1.16_14 (2021-02-18)
Old Night Sky improved :
Stars are brighter (pre-Beta 1.5).
Resolution increased.
Stars shape improved. 
Added greystars.png (between Beta 1.5 and 1.2.5) available in the pack. Rename it night.png if you want to use it.

v1.16_13 (2021-01-25)
Old Night Sky improved: removed moon phases (pre-1.0.0).

v1.16_12 (2021-01-24)
Added the add-on 'No Enchantment' (pre-1.0.0).
Old Water improved: added invisible underwater particles (pre-Beta 1.8).
Grass & Foliage improvement: grass block held in hand and in inventory has an accurate color.

v1.16_11 (2021-01-23)
Nether Fog improved: added invisible Nether air particles: ash, white_ash, crimson_spore, warped_spore.

v1.16_10 (2021-01-22)
Added Old Nether Fog. The fog has a darker tint (#1b0404 on screen) (pre-1.13.1) & no color variation for biomes (pre-1.16).

v1.16_9 (2021-01-13)
Old Night Sky improved (stars size reduced slightly to match pre-1.3.1).

v1.16_8 (2021-01-09)
Old Night Sky improved (accurate constellations & increased resolution).
Underwater fog improved (it gets darker as we go deeper).
Swamp water color restored.

v1.16_7 (2021-01-06)
Added Old Night Sky (pre-1.3.1) Stars are larger.

v1.16_6 (2021-01-05)
Added Nightvision.
Overworld lightmap improved (caves darkness & surfaces at night both match pre-Beta 1.8).
Nether lightmap improved to match pre-Beta 1.8.
The End lightmap improved to match 1.0.0 (but whith white color).
The End Sky noise improved (texture repetition is less visible).
Grass & Foliage improved (grass is greener in cold biomes & forest biomes).

v1.16_5 (2020-12-30)
Improved Grass & Foliage with temperature variations for biomes.

v1.16_4 (2020-12-29)
Added Old Lava texture.
Removed Grass & Foliage because not satisfied with them (temperature variations for biomes have been developed since Alpha 1.2).

v1.16_3 (2020-12-28)
Grass & Foliage experiment: no temperature variation for biomes.

v1.16_2 (2020-12-24)
Improvements:
Water surface matches pre-1.13.
Water overlay restored (water through glass is no more white).
Underwater corrected.

v1.16_1 (2020-12-20)
Overworld surface at night matches pre-Beta 1.8. (caves are no more completely dark).
The End sky improved (The End sky is darker with colorful noise).

v1.16_0 (2020-12-08)
Pack by Sencie.