In an interview for Adobe's blog NASA has revealed some of the processes its scientists use to transform technical data into images that the rest of the world can appreciate and understand. From simple tasks, such as straightening and cropping, to compositing multiple layers of scientifically calculated color, the agency uses programs including Adobe Photoshop to interpret the sometimes quite abstract images sent back to Earth from devices such as the Hubble Space Telescope and the Mars rover.

The scientific integrity of the images is of primary importance

In the interview, NASA makes it clear that the scientific integrity of the images is of primary importance, but says the enhancements it uses polish pictures, and only compensates for the short-comings of the cameras and the conditions in which they are working.

A simple example is the rotation of images taken by the Mars rover that were intended to be used to make a panoramic joiner of the planet's surface. As the rover is often standing on a rock or resting on an uneven area while recording, the horizon of the images is sometimes far from straight. NASA shows the original composite, but then uses fixes for the final image to make it more aesthetically pleasing. Software is also used to combine left- and right-eye views from the rover's camera pairs so that 3D images can be created.

The process allows us to see things we wouldn't otherwise be able to perceive

Other cameras produce images created from particular wavelengths of light, such as the Wide-field Infrared Survey Explorer. This can record individual greyscale photos from a number of specific bands of the spectrum, which can then each be colorized in software before being combined in Layers to create a full-color picture. As these are often taken from the non-visible spectrum the process allows us to see things we wouldn't otherwise be able to perceive.

In other cases, images from more than one telescope are combined to make the most of different types of data collected. An example given is a picture of the Sombrero Galaxy that is a combination of images from the Spitzer and Hubble telescopes, one in color infrared and the other recorded from light that would be visible to humans.

Imaging scientists have to be careful not to delete or remove stars,
planets or whole galaxies with a sweep of the wrong brush

The danger comes of course, when these images are being cleaned up having been through global changes such as curves and levels. In removing local defects in the image, and the effects of dust on the lens or in the atmosphere, the imaging scientists have to be careful not to delete or remove stars, planets or whole galaxies with a sweep of the wrong brush. Equally, it is important to remove these systemic defects so that they aren't mistaken for Heavenly bodies that actually don't exist.

For more information read the full interview on the Adobe blog.