Try different band combinations and contrast enhancement Edit layer properties and try a few different band combinations and contrast enhancements.įor good visibility of vegetation try Red: Band 5, Green: Band 4 and Blue: Band 1.įor a more natural look try Red: Band 3, Green: Band 2 and Blue: Band 1. Load up your favorite GIS desktop software, QGIS for me, and add your new TIFF file.ħ. Press OK and choose where you want your composite image to reside and give it a useful name (do not forget to add the. You can select Channels and reorder by choosing ‘Subset…’ (I usually include bands 1-5) and also select file format in the ‘Header’ drop box (I always stick with GeoTIFF format). Press Ctrl + R to open ‘Set Image File Format Change Specifications’ Set Image File Format Change Specificationsĥ. This is not critical for this exercise but is useful to visually inspect the image inside MultiSpec).Ĥ. For the ‘Set Display Specifications’ dialogue press OK (Try setting Bands to Red: 5, Green: 4 and Blue: 1. Go to File > Open and select all bands you want to composite into one image. The process I give below is a simplified explanation based on the MultiSpec tutorial.Ģ. I keep it at C:MultiSpec for simplicity.Ī comprehensive guide on how to composite images has been written up by the creators of MultiSpec and is available here. Download and extract to a folder of you choice. If you are a Windows or Mac user I suggest you try out MultiSpec. The next step is to composite these bands to make a coloured image to load into your GIS. For L7, that is 9 TIFF files about 60mb each except band 8 which is higher resolution band for pan-sharpening usually 200mb+. Once extracted you have a TIFF (.tif) file for each of the bands of the image. tar.gz file which can extracted using built in Windows functions or 7Zip. Once the image file is downloaded you will have a compressed. Shortly we will have Landsat 8 – it has been launched and more free imagery is not far off! Up until recently L5 was still working producing quality images but is now out of service. Note that images from L7 2003 onwards have lines of no data caused by a faulty sensor. Often you can download them directly from the basket, but sometimes they need processing time which can take a day or two. I find the USGS Global Visualization Viewer the best way to sort through and download images. This is a valuable resourse of historic and recent course resolution images covering most of the earth. As most GIS users will know the Landsat archive of satellite images is available for free download from USGS.
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