Commonly Asked Imagery Questions

These are the most frequently asked aerial and satellite imagery questions by Apollo Mapping clients. If you have additional imagery and/or order questions, please reach out to at any time!

This 30-centimeter WorldView-3 image was captured over rural, western Argentina on April 26, 2016. Satellite imagery purchased from Apollo Mapping such as this WorldView-3 data can be opened with a free imagery viewer listed here.

How do I view my imagery? Why is it all black when I open my image?

If you are having issues viewing your imagery, it is possible that you opened the raw imagery data, or that you opened the 4-band image that is 16-bit. You can learn more about 16-bit depth imagery here. If you ordered processed imagery, make sure you are opening the TIF file with “color balance” in the title. If you only purchased raw imagery, it can be opened using a free imagery viewer, though you will need to apply your own custom color balance. A 4-band image can also be opened using one of these free imagery viewers.

Why doesn’t my aerial/satellite image match my other GIS/CAD base layers and files?

The images may not match the base layers you have as they both need to be orthorectified in order to line up. Alternatively, you may need to change your project coordinate system so that it matches the imagery coordinate system. Your project coordinate system is either set by the user or is assumed when the first dataset is loaded in many GIS applications. You might also try loading the imagery first or reprojecting your spatial files so they all have matching projections and datums.

Why does Windows Photo Viewer not work to open my image?

Likely the file is too large. Windows Photo Viewer is meant to open much smaller and less complex images. We recommend using a free image viewer to load your images. Also, if you ordered a processed image, make sure you are opening the TIF file with “color balance” in the title.

What is a 4-band image? Or even a 6/8-band image?

Additional multispectral bands, including the near-infrared (NIR) band, are used in spectral analysis for a variety of applications such as forest health and fire damage assessments. The image above is a 50-cm Pléiades 1 false color or color infrared (CIR) view of Hatay, Turkey – areas in bright red represent healthy vegetation.

A 4-band image is a data file that includes the standard color bands the human eye sees (i.e., red, green and blue) plus additional spectral bands, such as near infrared (NIR), that humans cannot see. 6 and 8-band images include the standard bands in a 4-band image, but have additional spectral bands such as yellow and coastal. Commonly, the additional bands humans cannot see are used for spectral analysis. More specific descriptions on each satellite’s band combinations can be found here.

Where do I find collection time and other metadata for my images? What are the raw files?

All raw images have an associated metadata file (often an .XML file) that contains information like collection time, the satellite that captured the image, etc. For directions on how to find collection information for your imagery, click here. The additional metadata files found in the raw folder are used to make color balanced and orthorectified products, please keep a copy of them along with your processed imagery.