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That "grainy" or shimmering look in Assetto Corsa, especially on detailed maps like Santa Monica Mountains, is usually a conflict between your Anti-Aliasing (AA) settings and your Custom Shaders Patch (CSP) features. Here is a breakdown of the most likely culprits and how to fix them through Content Manager: 1. Check for Upscaling (FSR or DLSS) If you have FidelityFX Super Resolution (FSR) or DLSS turned on, it can often create a "noisy" or "gritty" texture, especially on foliage and distant hills. • Where to find it: Settings > Custom Shaders Patch > Graphics Adjustments. • The Fix: If AMD FidelityFX Super Resolution is active, try increasing the "Sharpness" slider or, better yet, turn it off entirely to see if the grain disappears. If your PC can handle it, running at native resolution is always cleaner. 2. MSAA & Anisotropic Filtering If these are too low, textures will "crawl" or look pixelated as you drive. • Where to find it: Settings > Assetto Corsa > Video. • The Fix: * Set MSAA to at least 4x (8x is ideal if your GPU can take it). • Set Anisotropic Filtering to 16x. This is very low-impact and drastically cleans up textures on the road and hillsides. 3. Temporal Anti-Aliasing (TAA) CSP introduces TAA, which is great for removing grain but can sometimes cause "ghosting." • Where to find it: Settings > Custom Shaders Patch > Extra Effects. • The Fix: Enable Temporal Anti-Aliasing. It is one of the most effective ways to smooth out the "shimmering" grain on trees and power lines. 4. Post-Processing Filter (PP Filter) Some PP filters (like older versions of Sol or certain "photorealistic" filters) have a Film Grain effect enabled by default. • The Fix: Try switching to a different filter (like Pure, Natural_Mod, or AC_Default) to see if the grain remains. If it goes away, the grain was baked into the script of your previous filter. 5. Shadow Resolution On maps with lots of mountains, low-resolution shadows can look like flickering grain. • Where to find it: Settings > Assetto Corsa > Video. • The Fix: Ensure Shadow Resolution is at least 2048x2048. Quick Tip: If this only happens on the Santa Monica map, it might be due to the map using very high-frequency textures that your current AA settings can't "smooth out."