Real-time shadows from blocks, trees, and mobs along with smooth terrain reflections on water require extra graphics work compared to vanilla Minecraft. If your frame rate drops in dense areas, you can tune your settings without losing the pack's clean lighting.
Adjusting Vanilla and Loader Distances
1. Open Options > Video Settings.
2. Lower Render Distance slightly so fewer distant chunks need lighting and water reflection calculations.
3. If your shader loader provides a Shadow Render Distance or Max Shadow Distance slider, reduce it so clear shadows still appear around nearby mobs, trees, and blocks without rendering far across the horizon.
4. Lower Entity Distance in crowded farms or villages to limit how many distant mobs cast shadows at once.
Using Shader Pack Options
1. Go to Options > Video Settings > Shader Packs.
2. Open the Shader Pack Settings button (usually in the bottom-right corner or beside the pack name).
3. Look through the available lighting, shadow, or reflection options and step down any high-cost toggles one at a time, clicking Apply after each change until your frame rate feels smooth during both sunny days and dark nights.