Hi there Guy'sI am trying to make a Photoreal ground texture for a small airstrip called "Rowland Flat" in the Barrossa Valley South Australia.Can anyone point me in the direction of a tutorial for making a blend mask for photoreal scenery using Gimp 2.I have been using different resourses ie"Modifying Default Airport Terrian with SBuilderX/OZX Developers Guide,{Making scenery for country airstrips}""to try to work out what is going on but to no avail.I am able to create a BGL that is photoreal in SBuilderX that is the size of the initial BMP but after changing the INI file adding [source2] etc...and trying to compile with my blend TIFF resample does not seem to work.It just flashes and no new BGL is produced.Any help or Direction would be much appreciated.RegardsMichael Haines

Can you post your .inf file?What I do in GIMP, is first load my tiff (I use Geotiff so I don't have to mess with the parameters in inf, but I have GIS software to help me!) in the normal RGB mode. Then I create a new layer set to "white" (255,255,255) and edit the layer. I adjust the layer properties setting transparent to 40-60% so I can see my main bitmap "underneath". I use selections to set the area that's "all black" (and then fill with black) and "all white", then invert the selection so I am left with a selection where I want to get gray (to do the actual blending). Then I play with the gradient tool and the dodge/burn tool to get the "grays" I want. When you use those tools, try things like "additive" or "subtractive" modes.An alternative is to load your image and convert to 8 bit grayscale. Then again use selections and bucket fill to set your all black and all white areas. The transition area is now gray from your original image. Sometimes just using that gives a good result, but again experiment with gradient and dodge/burn. scott s..

Can you post your .inf file?What I do in GIMP, is first load my tiff (I use Geotiff so I don't have to mess with the parameters in inf, but I have GIS software to help me!) in the normal RGB mode. Then I create a new layer set to "white" (255,255,255) and edit the layer. I adjust the layer properties setting transparent to 40-60% so I can see my main bitmap "underneath". I use selections to set the area that's "all black" (and then fill with black) and "all white", then invert the selection so I am left with a selection where I want to get gray (to do the actual blending). Then I play with the gradient tool and the dodge/burn tool to get the "grays" I want. When you use those tools, try things like "additive" or "subtractive" modes.An alternative is to load your image and convert to 8 bit grayscale. Then again use selections and bucket fill to set your all black and all white areas. The transition area is now gray from your original image. Sometimes just using that gives a good result, but again experiment with gradient and dodge/burn. scott s..

Hi there ScottThanks for your reply.Your instructions have shed some light on what I am doing wrong.Guess I will need more time playing with GIMP@ to nail this.Seems like I have messed up in the layer proccess of GIMP2 I did not create another layer but another BMP the converted to TIF for the blend mask and saved it as a seperate file in the work folder of SBuilderX. :( Here's a copy of my INI File just for a laugh.[source] Type = MultiSource NumberOfSources = 2[source1] Type = BMP Layer = Imagery SourceDir = "." SourceFile = "L16X116122X116128Y78959Y78963.BMP" Variation = All NullValue = 255,255,255 Channel_BlendMask = 2.0 SamplingMethod = Gaussian ulyMap = -34.558597459864 ulxMap = 138.938598632813 xDim = 1.07288360595703E-05 yDim = 8.83509452520581E-06 [source2] Type = TIFF Layer = None SourceDir = "." SourceFile = "L16X116122X116128Y78959Y78963_B.TIF" SamplingMethod = Gaussian ulyMap = -34.558597459864 ulxMap = 138.938598632813 xDim = 1.07288360595703E-05 yDim = 8.83509452520581E-06 [Destination] DestDir = "." DestBaseFileName = "Rowland_Flat_MH" DestFileType = BGL LOD = Auto UseSourceDimensions = 1 CompressionQuality = 100Kind RegardsMichael Haines

Are you trying to compile this using SBuilderX, or running resample directly? If you haven't, you might try opening up a command window and run resample in it so you can see whatever info resample is giving you as it runs (it isn't always that helpful as to specific problem though). A quick look at your .inf I don't see any obvious problems.scott s..