This is a simple Minecraft Fabic mod that adds a configurable zoom key.
There are other mods that have this same feature but this is my first mod and I'm using this as an excuse to learn Minecraft modding.
The motivation for this particular mod is that Minecraft 1.15 is out and I personally use Optifine which includes this same zoom feature. At the time of writing,
Optifine is being updated but I would like to have the zoom feature for when I make Minecraft videos.
By default the C key is mapped for zooming (as with Optifine) but you can change this in the Controls settings of Minecraft. If you already have the C key bound then you'll need to remap it before it'll work :o)
NOTE: This mod requires Fabric API mod: https://www.curseforge.com/minecraft/mc-mods/fabric-api