RE: Member Photos
September 5, 2016 at 1:54 pm
(This post was last modified: September 5, 2016 at 3:01 pm by Anomalocaris.)
It cleared up last night. I put the Sidereal tracking mount to the test. In general, when there is no operator error, it performed well. However, it is not sufficiently heavy duty to track with a heavy lens, like a Nikon 200-500, mounted off-center. The mount/lens combo is also insufficiently rigid to absorb vibrations from mild breeze, or remote cable release being moved about. I didn't have a chance to process the photos yet. So here are direct JPEG conversions of raw photos:
Orion nebula: The distortion in the shape of the star comes from lens vibration, not failure of the mount to track:
Andromeda M31: This image can use a lot of post processing through stacking multiple images. Andromeda's central bulge is so much brighter than the spiral arms it is impossible to capture both together in one image, even on a Nikon, which has some of the best dynamic range characteristics of any commercial digital cameras on the market today. Here you can see faint outlines of the dust lanes in the inner spiral arms. Outer spiral arms are completely lost. The full disk of Andromeda would span almost the entire frame. The small blob underneath Andromeda is a small satellite galaxy orbiting Andromeda.
Triangulum Galaxy M33: This should be an almost ideally perfect Spiral galaxy seen face on. But I am inexperienced and underexposed the picture. So all you see is a muddy blur with the faintest hint of spiral structure. M33 is at virtually the same distance from earth as Andromeda, but it only 1/10 as large.
Eagle Nebula M16: This is the tiny smudge near the center of the picture. It is a star forming region. What you see is a cloud of glowing ionized hydrogen being lit from inside by about 8000 newly formed stars. It is about 7000 light years from earth, and lies near the line of sight between the earth and the center of the Milky Way Galaxy. It seems dim because it is far further from the earth than any of the stars surrounding it in the picture.
Now for a picture of the same Nebula by a real camera and tracking system: Hubble Space Telescope took a famous picture of the central part of the nebula, The finger like structures are areas of over density in the nebula in which protostars are forming. It has been called "Pillars of Creation".
Orion nebula: The distortion in the shape of the star comes from lens vibration, not failure of the mount to track:
Andromeda M31: This image can use a lot of post processing through stacking multiple images. Andromeda's central bulge is so much brighter than the spiral arms it is impossible to capture both together in one image, even on a Nikon, which has some of the best dynamic range characteristics of any commercial digital cameras on the market today. Here you can see faint outlines of the dust lanes in the inner spiral arms. Outer spiral arms are completely lost. The full disk of Andromeda would span almost the entire frame. The small blob underneath Andromeda is a small satellite galaxy orbiting Andromeda.
Triangulum Galaxy M33: This should be an almost ideally perfect Spiral galaxy seen face on. But I am inexperienced and underexposed the picture. So all you see is a muddy blur with the faintest hint of spiral structure. M33 is at virtually the same distance from earth as Andromeda, but it only 1/10 as large.
Eagle Nebula M16: This is the tiny smudge near the center of the picture. It is a star forming region. What you see is a cloud of glowing ionized hydrogen being lit from inside by about 8000 newly formed stars. It is about 7000 light years from earth, and lies near the line of sight between the earth and the center of the Milky Way Galaxy. It seems dim because it is far further from the earth than any of the stars surrounding it in the picture.
Now for a picture of the same Nebula by a real camera and tracking system: Hubble Space Telescope took a famous picture of the central part of the nebula, The finger like structures are areas of over density in the nebula in which protostars are forming. It has been called "Pillars of Creation".