Image Products

Yes! The THEMIS standard processing is described in the documents here, but you are, of course, always welcome to ingest the published products into your favorite image processing tools. However, we also have created an online processing tool which allows you to complete your own specialized processing using the THEMIS toolset and the ASU-MARS computers. Many exciting and new features for this tool are being developed based on feedback from users like you.

Long, narrow images represent a single observation with the THEMIS camera.

Large, boxy "images" represent a mosaic of multiple, overlapping images collected throughout the mission and saved as a single file. Various image processing techniques may be applied to hide the edges of the individual images.

The THEMIS Standard Data products (EDR, RDR, ABR, & BTR) are not projected into any coordinate system. The pixels in these products maintain the time, row, and column ordering (per band) of the raw observation; this arrangement is commonly referred to as "camera coordinates". Be aware that the bands of the QUBE products are not spatially registered within a single image.

The THEMIS Special Geometry products (GEO, LOC, PBT, and DCS) are map projected, with the coordinate system details documented in the headers and/or available labels. The following guidelines are used in routine processing:

The THEMIS team provides several Standard data products and several Special data products through this website. All products are described in detail in the Product and Geometry documentation.

The five color filters of the THEMIS VIS camera do not span the full range of colors available to the human eye, so extensive processing, and an artistic touch, is applied to convert a raw image into an approximately "true color" image. Several of the THEMIS Team members are experts in VIS spectroscopy and have used their experience with the Hubble Space Telescope (HST) observations of Mars to generate a limited number of VIS color images. Their multi-step process:

The four panels of the IR-DCS browse product are (from left to right):

• DCS where RGB = bands 875
• DCS where RGB = bands 964
• DCS where RGB = bands 642
• Stretched Brightness Temperature

The four panels of the IR-DCS browse product are (from left to right):

• DCS where RGB = bands 875
• DCS where RGB = bands 964
• DCS where RGB = bands 642
• Stretched Brightness Temperature

The nominal resolution of the IR camera is about 100m/pixel.
The nominal resolution of the VIS camera is about 18m/pixel.

The resolution of either camera can be modified by spatial summing applied onboard before the images are downlinked; the image header and the Image Data table on the Details tab include the actual pixel resolution for each image.