Imaging the Skies Over Bavaria

Surfing through the AstroBin site’s collection of user generated astrophotos we were struck at this vivid example of M16 “The Eagle Nebula.” The image has a depth  and contrast we’ve never seen before. Created using “Hubble Pallet” filters, the rich blue (Oxygen III) surrounding the “Pillars of Creation” structure is highlighted by the ruddy bland of reds (Sulfur) and greens (Hydrogen-alpha and Nitrogen) in the “folds” of the surrounding dust clouds. The blackness of space at the edge of the dust and gas cloud is preserved against all the colors. 

The central complex star-forming region of glowing ionized atoms and molecular clouds sculpted by radiation pressure  is shown  in this crop of the central portion of the M16 photograph.  The high quality of the processing is evident upon close-up review, where dark globules are found suspended in the Oxygen-rich medium around the “Pillars.”

 

We found out that the image was actually posted to Paul Schuberth’s AstroBin.com account. He’d taken this image from Bavaria in Germany using a fast 10″ Newtonian outfitted with our BIG Paracorr Coma Corrector — an accessory virtually mandatory for creating sharp, wide-field images with fast Newtonians. 

 

Another delightful “Hubble Palette” image he produced is this “Bubble Nebula” (NGC 7635) image taken with the same imaging setup.  This emission region features a glass-like bubble formed by the shock front of stellar winds that runs into cooler, denser material in the surrounding molecular cloud. The radiation from the star in the bubble heats up the  element-rich cloud and causes it to glow a bronze color in the image. The bubble is about 10-light-years across.

 

 

In this cropped image highlighting the “bubble,” the bright star toward the bottom of the bubble is driving the expansion.  It is a young, massive (45 solar masses) O-type star that is thousands of times more luminous than our sun. It will end its life as a neutron star or black hole after undergoing a a supernova  explosion.  

Looking like a post-modern art painting, Paul’s Iris Nebula  portrait is stunning.  Named after the colorful Iris flower, light from a bright star is reflects as blue off the knotty web of dust in the cloud that surrounds it. The reddish clouds contrasting with the blue nebula are caused by glowing gas energized by the star. For this image his camera filters were used to capture the luminosity (black and white) of the object as well as red, green, and blue colors. 

 

 

Our BIG Paracorr Type-2  turns fast Newtonians into astrograph-quality scopes by fixing the problem inherent in all fast parabolic mirrors: coma. This off-axis aberration makes round stars look like little comets which all point to the center of the field.  By making color-free coma corrections to the optics, BIG Paracorr allows a fast f/3 Newtonian’s mirror to act like a longer f/12 mirror. Stars at the edge of an f/3 mirror are 25-times smaller than if the coma was left uncorrected! For amateurs and professionals using CCD formats as large as 52-mm  on the diagonal, sharp, wide-field imaging across the entire field of view becomes possible with a BIG Paracorr Type-2 on these scopes.

 

 

For years, BIG Dob owners were forced to climb ladders to enjoy the deep-sky views afforded by the mega-sized mirrors in their scopes. Making telescopes tubes with a more reasonable height would require faster mirrors — meaning diminished optical quality due to coma. Enter BIG Paracorr: by fixing the optical flaws inherent in faster mirrors the tube can be shorter — making large ladderless Dobsonian possible! You can read about this New Dobsonian Revolution (PDF) in an article from Astronomy magazine.

 

Newtonians as fast as f/3 with standard 2″ focusers, can benefit by employing our  2″ Paracorr Type-2 (VIP-2010). It’s especially useful for scopes on non-tracking mounts because your object is now sharp anywhere in the field, not only in the center. This unit features a “Tunable Top” to correct coma with 1¼” or 2″ eyepieces. Unscrewing the Tunable Top allows this smaller Paracorr to work with Tele Vue imaging system components to permit use with SLR and CCD cameras. For imaging, APS size formats 27-mm diameter are recommended to minimize field vignetting.

 

• More about our 2″ and 3″ Paracorrs on the website (mobile version)
• BIG Paracorr literature and mechanical drawing (PDF)
• For connecting BIG Paracorr to a camera consider Precise Parts
• For more images see BIG Paracorr User Profile: Jay Butler blog post