"The LOD5 gridsize is actually 257x257. I know this for sure, because I usually write the data section directly into the bgl files. That's right. I can make landclass bgl files without using resampler at all..."Now that is really slick Christian. how does that work?

That's quite hardcore. The photoshop way is much easier, so you should concentrate on that instead...Cheers, Christian

Don't worry, I wasn't even going to go there.Back to the grayscale conversion errors in Photoshop. I am puzzled still. I sent my .tif to a friend by email and he converted it to grayscale using Paintshop Pro and no errors. I wonder if it could be some obscure setting in Photoshop?

I get the feeling you don't know all that much about landclasses yet. Have you read my tmfdoc (here at avsim)?First off, colours don't mean anything!You need an 8bit picture (preferentially palette). Now in the palette index set a colour (say set colour number 20 to green). Now paint this colour onto a new 257x257 raw picture. Now send the raw file through the resampler and you should get where ever you painted 20 the appropriate landclass (read the sdk to find out what 20 means). There rest will be water (if its colour 0). get this to work first!The next bit will be converting your tiff file. You'll have to produce a similar file as you did with your handpainting, eg 8bit and each colour mapped to a landclass value.You could use b&w but it's not easy to see whats what...Cheers, Christian

Boy is my face red. I FOUND the problem with my Photoshop setup. Thanks to a friend in Norway who pointed me in the right direction. Under color settings there is an obscure (to me) 8 bit dithering check box. I unchecked it, thereby eliminating the dithering and everything works as it should. Take a look below: