I recently discovered that, from below y-level 128, I couldn't see any blocks above y:128. After some experimenting, I found that the cause was the 64x texture pack I was using. With any texture pack larger than 16x, I cannot see blocks above y:128. Is there any fix for this? I am using Optifine 1.4.5 HD U D3 to provide the enhancements necessary for a >16x texture pack.