First off, you should be able to zoom out so you can right click on the edge of your map to give access to a context menu With calibrate and properties submenus. Properties also lets you calibrate.
You can have 3 different images, each with its own calibration, as part of a "map set", the main map, land use map, and mesh map. But the default is you add the "main map" and the same image is used as the land use map and mesh map. However, each of the three maps has its own calibration, so you need to ensure that all three are identical if you are using a single bitmap. When you use different tools in SBuilder, it will shift to the appropriate map, and if you forget to adjust all 3 calibrations it can be confusing.
As far as the photo map, that only is needed if you are going to make custom photo terrain with seasonal and night variations. All the photos and main map share the same calibration. Typical is you would have a photo bitmap of summer, or maybe spring, and create the variations in a photo edit program, so the final photos are the same pixels dimension. The default is that SBuilder uses your main map for every season/night.
Where I have made mistakes, is I add a map and calibrate it, then later I want to add some landclass so switch to the landclass tool and forgot to calibrate the map for use in landclass. You need to click on photo tool to get SBuilder to use the proper calibration. If you are using different images it's pretty obvious which one is in effect, but it's when you use just a single image you can get confused. Again, the fix is to make all 3 calibrations the same when a single image is being used.
scott s.
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