This picture cannot be taken with a single exposure. There is a 128x difference in brightness between our Moon and the moons of Jupiter. The only way to get a photo like this is to take separate exposures of Jupiter and the Moon, then combine them into the same picture.
In this case, I placed placed the celestial objects right next to each other to enable size comparison. Both objects were captured with the same magnification. Seen side-by-side, you can see that the Jovian system is spread out at about 1/3 the apparent lunar diameter.
Click on the picture above for a larger view. Or, here is the full-res version and the full-frame version. Technical details, if anyone cares:
* Lens (both shots): Canon 70-300mm zoom at 300 (480mm equivalent for 35mm magnification).
* Moon: 1/45 second, f/9.5, ISO-200. 25 shots stacked with RegiStax.
* Jupiter: 1/2 second, f/5.6, ISO-800. 25 shots pared down to 10, then stacked with RegiStax.
In case you hadn't noticed, I'm really enjoying astrophotography with a camera and tripod! But of course it won't last much longer -- this is Oregon, after all, and the rainy season is on the way. Oh well; fortunately we have APOD, rain or shine!
