The upper image was taken at prime focus and then enlarged 200 percent in photoshop. The lower image was taken with 2x barlow and is actual size. The air was too turbulent for the magnification. This was the first time I set up the ETX 125 in Polar Alignment. Successful alignment on the first try. It makes the telescope look much more astronomical.
Archive for April 2009
Saturn 4/25 Leave a comment
Third Quarter Moon Leave a comment
On the roof at 5am this morning with chair and binoculars. Perfect third quarter moon in the southeast, with Jupiter in the east. Very clear, light wind. Here’s what I saw through the binoculars:
Alright, that crater wasn’t quite so prominent, but the two mountain ranges seemed about as defined as the drawing, which is by Galileo Galilei published in Sidereus Nuncius, 1610. As Galileo describes it, “brighter ridges of mountains rise loftily out of the darkness.”
The lower range is the Appenine Mountains, and the upper range the Alps. The best guess for Galileo’s crater is Albategnius, from Ewen A. Whitaker in “Galileo’s Lunar Observations and the Dating of the Composition of ‘Sidereus Nuncius,’ ” Journal for the History of Astronomy 9 (1978): 155-69.
Plato, Imbrium, Frigoris, Iridum Leave a comment
A bit oversharpened to bring out the subtle colorings of the floor of Plato and the maria.
The last exposure before I accidentally unplugged the controller. Registax V was just released, and it has an automatic feature to estimate registration points and align in one pass. All I did in photoshop is autolevels, cropping, and convert to greyscale before saving to web as jpeg. No extra sharpening.
Bay of Rainbows: Registax 4 vs Registax 5 1 comment
April 5, about 9pm. Philips SPC900c webcam, ETX-125 telescope f/15 prime focus. Very steady at the eyepiece even at 300 power. Conditions for imaging the moon ideal. Calm night, clear skies, 60 degrees. The moon is 82% illuminated.
Redone with Registax V. About 40 alignment points.
Inwood Star Fest Dyckman Fields April 3: Umbrellas and eypieces required 1 comment
Over fifty people attended the Inwood Star Fest at Dyckman Fields April 3. Adrian Benepe, the New York City Parks Commissioner had the lights in the park turned off from 8:15 pm to 10:45 pm. The National Weather Service had rain predicted for April 3, and it rained all day. The Clear Sky Clock held out hope for eight hours of clear skies starting at 7 pm. About 6 the skies cleared, only to cloud over at 7, and 8, with a few sprinkles and lightning. The crowd was pretty game; Jason Kendall made a few remarks, I kept looking at the sky. About 9:30, a few breaks in the clouds showed the Moon, Saturn, Castor and Pollux, Sirius, Arcturus, and finally the entire Big Dipper and Polaris. I pointed my telescope at the Moon, and the other astronomers there found Saturn and the Moon as well. Everyone got a chance to look through a telescope. Although I planned to do astrophotography, there were a line of kids at my telescope. The eyepiece was too far off the ground so I took my eyepiece case (an American Tourister suitcase) and used it as a step, and all the kids could see the craters, mountain ranges and maria on the moon. Something to remember for next time, for, according to Jason, the Parks Commissioner is willing to do another Star Fest. So Dyckman Fields becomes the unofficial Dark Sky Park of Manhattan.