This problem has just occurred and for some reason I get patches of darker colours in oceans.It shows almost perfect edges which is obviously unusual. There is a pic below, I do not get this problem when looking behind the aircraft, only in front. I use REX Sparkling effect for my waters and would like to know if anybody knows why this happens. Many thanks as always.

This problem has just occurred and for some reason I get patches of darker colours in oceans.It shows almost perfect edges which is obviously unusual. There is a pic below, I do not get this problem when looking behind the aircraft, only in front. I use REX Sparkling effect for my waters and would like to know if anybody knows why this happens.

From your picture it looks like a normal waterclass issue. Basically waterclass works the same way landclass works. In FSX there is a main waterclass file and landclass file that tells FSX where to place certain textures on the ground and in the water. The way it works is that the waterclass file splits water into many different categories like tropical, deep, inland, etc. where as landclass tells the sim where to place city, farm, residential, and swamp textures, etc., then FSX knows which water or ground textures to place in those certain areas. The problem with waterclass and landclass that the borders are square, which in many cases is fine for land textures since they blend a little better and aren't as noticable. However, when you get a transition in water textures from deep to shallow and the textures are different colors its a lot more noticble. You can see these squares in the water very easily when you fly around the tropics and notice the transition from deeper water to shallow tropical. The good news is that there are four ways to fix or disguise this problem so that its not as noticible. First you could use a freeware tool like SBuilderX which will require that you have the FSX SDK installed, and then you can modify the waterclass to your liking and make the water more of the same class or style which will eliminate the squares. The problem with doing this is that you will have to do it for each location that you want to modify, so if this is a problem that bothers you wherever you fly then it will take a lot of time and work. However, if its only a certain area then you can fix it quit easily. I always hated the tropical water that is displayed in the Rio and Miami area and the squares that go along with it, so for those two areas I placed deeper water waterclass files that blend with the water outside that area. The second way you can disguise it is to play with the REX water color settings and modify them, which is different than the water animations which in your case is the sparkling set. It will require some trial and error to get it the way you want, but depending on the waterclass for the area in which you have a problem it might not fix it completely. A 3rd option is to use FSWater Config and tweak the shaders a bit. I personally like one of the default settings called Orion. This will also fix the milky looking water reflections you get at night time with a full moon. It's a free tool and can be found by doing a google search, however it wont work with DX10 preview. Lastly, if your using a weather program like ASE, you can limit the upper visibility limits which will add a haze and will mask it a little bit so that its not so noticible. I set my upper vis distance limit in ASE to 60 miles which seems to give a pretty good look over water and helps disguise some of those imprefections you see when at higher altitudes. The other day I was flying in real life from Dallas to Miami and it was a fairly clear day, but at 37000' there was still haze which matched up pretty well with how I have it set in ASE. The fact that you say you can't see it when looking backwards towards the a/c does seem funny though and would suggest that it could be something else, although the way waterclass looks and the random way in which the textures are placed does lead me to believe that it is just coincidence that sometimes when looking back you dont see the squares. Although if you fly over the squares in the photo you provided and cant see them when looking back after you passed them, then I have no idea, expect that they aren't noticible because of reflection of the water. My guess however that its just waterclass squares. Hope this helps.