Need help identifying a bug

[Parascythe]

I have this problem across multiple packs, what happens is every few minutes in-game my screen will zoom in slightly without me even touching the keyboard then it will zoom back out. I use optifine on infinity with shaders and that's about it.

Has anybody experienced this before? I have also unbound every single key except for movement and inventory keys and it still happens.

It's such a hair ripping bug lol.

 

[Aetherpirate]

Are you playing on a laptop? Perhaps you are brushing the touchpad accidentally and it zooms.

 

[Parascythe]

Are you playing on a laptop? Perhaps you are brushing the touchpad accidentally and it zooms.

No sorry, just a desktop computer. I did not know a touchpad could zoom in minecraft though, however I have all keybinds disabled except movement.

 

[rhn]

I have this problem across multiple packs, what happens is every few minutes in-game my screen will zoom in slightly without me even touching the keyboard then it will zoom back out. I use optifine on infinity with shaders and that's about it.

Has anybody experienced this before? I have also unbound every single key except for movement and inventory keys and it still happens.

It's such a hair ripping bug lol.

Do you have any temporary Haste buffs going on? Beacons, Baubles, potions? A change in movement speed will change the view a little bit, making it look like it zooms.
It could be that one of your items apply a buff badly and when it is refreshed it actually runs out for a split second.

 

[DeathOfTime]

Just google searching for possibilities.
Are the optifine keybings also set? It seems it has a built in zoom feature (or did).

there don't appear to be to many search results. Will try again and edit this post if I find anything of interest.

Edit
http://ftb.gamepedia.com/Optifine

OptiFine adds two new Control hotkeys as well: a "Zoom" key and a "Cinematic Camera" key. The Zoom control (default LControl), when held, zooms in the camera significantly, akin to the effect gained by the user of a scoped weapon in a first-person shooter. The Zoom control is very useful for both scouting and Bow aiming. The Cinematic Camera key (default None) causes the camera to actually have inertia. Moving the mouse no longer simply whips the camera around, it causes the camera to smoothly turn in the direction of the movement. Cinematic Camera is automatically used whenever the Zoom control is held, but otherwise its usefulness is somewhat limited.

It is likely either optifine, or something interacting negatively with optifine that is in every modpack you are playing.