Sentinel-2 is sharper and fresher; Landsat reaches back to 1972. Learn when to use each free dataset β and when the best answer is both.
Archive: October 2026
97 stories published in October 2026
A step-by-step guide to downloading Sentinel-2 imagery into QGIS: account setup, smart searching by cloud cover, choosing Level-2A data, and loading the right band combinations.
WebODM turns drone photos into free orthophotos and 3D models. Learn the flight settings that make it work, how to run your first task, and how to check your results.
NDVI turns satellite imagery into a plant-health map in minutes. Learn the formula, which Sentinel-2 and Landsat bands to use, and how to style and interpret the result honestly.
Overlap, altitude, and speed decide whether a drone mapping flight succeeds. Learn the settings behind good photogrammetry and the pre-flight checklist that prevents failed reconstructions.
Free open aerial imagery is often sharper than satellite data for local mapping. Learn where national programs, OpenStreetMap, and web services offer it β and how to use it legally.
QGIS is free and ArcGIS is the industry standard β but which should a beginner learn first? Compare cost, jobs, and ecosystem, and learn why the underlying skills transfer either way.
Turn a drone elevation model into readable contour lines in QGIS. Learn how to prepare the DEM, choose the right interval, style index contours, and check accuracy.
A GeoTIFF is an image with location tags that place it on the map. Learn how georeferencing works, what cloud-optimized GeoTIFFs change, and how to use them in QGIS.
QGIS is free and powerful, but beginners need a clear path. This step-by-step tutorial covers installing, adding data, styling, querying, and exporting your first map.
Sentinel-2 offers finer detail and frequent revisits; Landsat offers decades of history. Here is how to choose the right free satellite data for your mapping project.
WebODM turns overlapping drone photos into maps and 3D models for free. This beginner workflow covers flight planning, processing, and checking your first orthomosaic.
LiDAR uses laser pulses to build detailed 3D maps of terrain, forests, and cities β even under tree cover. Here is how it works and when to use it.
QGIS print layouts add titles, legends, scale bars, and clean design to your map. Here is how to build, style, and export a professional layout.
QGIS, PostGIS, GeoServer, and Python libraries now cover most GIS work for free. Here is the open-source stack that can replace commercial GIS for most users.
Georeferencing gives a scanned old map real coordinates so it can be compared with modern data. Here is how to pick control points, transform, and check the result in QGIS.
Drone photogrammetry can produce elevation models for flood, construction, and land analysis. Here is the difference between surface and terrain models and how to use them.
Free DEMs from SRTM, ALOS, Copernicus, and national lidar programs cover most of the world. Here is how to choose the right elevation source for your project.
OpenStreetMap lets anyone improve the world's free map. This beginner guide covers editors, tags, accuracy, and using OSM data in your own projects.
QGIS is free and ArcGIS is the industry standard, so beginners face a real choice. This comparison covers cost, learning curve, jobs, and which tool to start with depending on your goals.
You do not need a budget to work with satellite imagery: several major programs give it away. This guide compares the best free sources, their resolution, and how to actually download data.
Drone maps look precise, but their accuracy depends on overlap, ground control, and camera geometry, not just the drone. This guide explains how photogrammetry works and what controls its accuracy.
GIS careers range from technician roles to spatial data science, and the path in is clearer than it looks. This roadmap covers the skills employers actually ask for, the portfolio that gets interviews, and realistic timelines.
OpenStreetMap is the free map of the world, built by volunteers, and anyone can improve it. This beginner's guide walks you through your first edits, from creating an account to mapping a building correctly.