Welcome to Images From The Cosmos
For those interested in the technical side of how my finished astrophotos were created, please read below.
The 11-inch Celestron is used at F/30 for planetary photography; it is used at F/6.3 and F/2 for wider view (.5 degree and 2.3 degrees respectively) deep-sky photography. The white 3-inch Pentax F/6.7 flat-field refractor (riding piggyback on the 11-inch) is used for wide-field (4 degrees) deep-sky photography. The 4-inch Celestron (upper right) is used to support a camera that takes very wide-field (60+ degree) views of the night sky. Cameras used are the Canon Rebel XT and the Canon Rebel XSi (both unmodified DSLR cameras) for deep-sky work. For lunar and planetary work an Olympus C-4040 Zoom camera operating in an afocal arrangement is used, or, alternatively, image projection is used with a DSLR camera. Auto guiding is accomplished by an Orion auto-guider camera connected to a laptop computer. All cameras are controlled remotely through the computer. Click on image to enlarge and read caption.
Some thoughts on technique: Telescopes used for planetary and lunar photography require longer native focal lengths and a high F-ratio (at least F/20 to 30) in order in order to achieve the necessary resolution for seeing surface or cloud belt detail. The 11-inch Celestron provides this and beyond using a 2x to 3x Barlow lens combined with the zoom feature of the Olympus C-4040. On the other hand, much fainter deep-sky objects require a telescope to operate between F/2 and F/8. Focal ratios greater than F/8 require considerably longer exposure time than lower focal ratios. The Celestron is capable of operating at F/6.3 or F/2 (using the Fastar setup). Thus, the Celestron scope is a highly versatile instrument suitable for photographing a wide range of objects. The Pentax operating at F/6.7 is reasonably fast, but the beauty is in its optical system: It provides a perfectly flat field of view of four degrees (eight full moons set edge to edge) with pinpoint stars out to the perimeter.
The final photos are always the result of several photos aligned and stacked (using RegiStax 5), the backgound light gradients evened out by use of GradientXTerminator, and then processed in Photoshop Elements using Neat Image to eliminate noise associated with long exposure times needed to photograph faint objects. Processing need not be tedious; it often is exciting because many features emerge from the data contained in the exposures that simply were not available for study prior to processing.
All deep-sky photos were taken either through a Lumicon Deep-Sky filter or a Baader UCH-S filter both of which suppress ambient city light and let through hydrogen and oxygen wavelengths that allow many faint nebulae and galaxies to be photographed much more easily. Without these filters it would be difficult to do backyard astrophotography near a city such as Santa Barbara CA, from where most of my images were taken.
The 11-inch Celestron is used at F/30 for planetary photography; it is used at F/6.3 and F/2 for wider view (.5 degree and 2.3 degrees respectively) deep-sky photography. The white 3-inch Pentax F/6.7 flat-field refractor (riding piggyback on the 11-inch) is used for wide-field (4 degrees) deep-sky photography. The 4-inch Celestron (upper right) is used to support a camera that takes very wide-field (60+ degree) views of the night sky. Cameras used are the Canon Rebel XT and the Canon Rebel XSi (both unmodified DSLR cameras) for deep-sky work. For lunar and planetary work an Olympus C-4040 Zoom camera operating in an afocal arrangement is used, or, alternatively, image projection is used with a DSLR camera. Auto guiding is accomplished by an Orion auto-guider camera connected to a laptop computer. All cameras are controlled remotely through the computer. Click on image to enlarge and read caption.
Some thoughts on technique: Telescopes used for planetary and lunar photography require longer native focal lengths and a high F-ratio (at least F/20 to 30) in order in order to achieve the necessary resolution for seeing surface or cloud belt detail. The 11-inch Celestron provides this and beyond using a 2x to 3x Barlow lens combined with the zoom feature of the Olympus C-4040. On the other hand, much fainter deep-sky objects require a telescope to operate between F/2 and F/8. Focal ratios greater than F/8 require considerably longer exposure time than lower focal ratios. The Celestron is capable of operating at F/6.3 or F/2 (using the Fastar setup). Thus, the Celestron scope is a highly versatile instrument suitable for photographing a wide range of objects. The Pentax operating at F/6.7 is reasonably fast, but the beauty is in its optical system: It provides a perfectly flat field of view of four degrees (eight full moons set edge to edge) with pinpoint stars out to the perimeter.
The final photos are always the result of several photos aligned and stacked (using RegiStax 5), the backgound light gradients evened out by use of GradientXTerminator, and then processed in Photoshop Elements using Neat Image to eliminate noise associated with long exposure times needed to photograph faint objects. Processing need not be tedious; it often is exciting because many features emerge from the data contained in the exposures that simply were not available for study prior to processing.
All deep-sky photos were taken either through a Lumicon Deep-Sky filter or a Baader UCH-S filter both of which suppress ambient city light and let through hydrogen and oxygen wavelengths that allow many faint nebulae and galaxies to be photographed much more easily. Without these filters it would be difficult to do backyard astrophotography near a city such as Santa Barbara CA, from where most of my images were taken.