This sequence shows the eclipse of Europa and the transit and re-emergence of Ganymede on March 13, 2004 between 8:11pm and 9:39pm EDT. The image below shows an enlargement of the image of Ganymede after it emerged from transit.

All pictures were obtained at about f/30 by Barlow lens projection directly onto the CCD of a Philips ToUcam Pro using the 10-inch f/6 modified Newtonian reflector at Clif's observatory in Perrineville. The telescope has an Orion three-element Barlow inserted on-axis between the diagonal and the primary giving an intermediate focal ratio of f/18. An additional Barlow outside the tube gives a final focal ratio of f/50. One-minute AVI files were taken at settings of 15 frames per second and exposures of 1/30th of a second. Processing was done by Registax-II using the best 300 images of 900 from each AVI file. Composites were prepared in Photoshop.

These are enlarged and contrast-enhanced images of Ganymede clipped from the above photos taken at 9:30 and 9:39pm EDT. Starry Night Pro simulation of the surface of Ganymede along with a resolution-impaired version is included to simulate the resolution of the actual photos. The limiting resolution of a 10-inch aperture is about one half arc-second, and the size of the image of Ganymede was only 1.6 arc-seconds across.