Imaging the Skies with the Tele Vue-NP127is
We’re quite impressed with Frank Wielgus’ exquisite collection of wide-field, deep-sky images on SmugMug. Photographed with a Tele Vue-NP127is APO refractor, the attention to image capture and software craftsmanship is evident in his collection of galaxies and nebulae. His images have often been selected as winners in the Amateur Astronomers Association of Pittsburgh’s Kevin J. Brunelle Photography Contest.
In his guest blog, Frank shows and tells us the story of his astrophotography.
I started astrophotography in the early ’90s using film. It was a Pentax camera with screw mount lenses, piggybacked on an SCT using slide film. Boy, I’m glad those days are gone! I have recently started using those lenses again on a wide field DSLR set up. I then moved to imaging through the SCT. At some point, I wanted to up my game in quality, and for me, that meant a refractor.
Ever since I first acquired Tele Vue Plössls in the early ’90s, I have always admired Tele Vue products. Quality, design, and locality of service were important considerations for me. For these reasons, the NP127is was a dreamed-for acquisition for a number of years. So when the opportunity arose and with the prompting of a good friend, I acquired one. I remember being blown away by the quality. Now stars look like stars and the sharpness with flat field are incredible things to see. Barring any unusual circumstances, this scope and I are in it together for the long haul.
I do most of my imaging from Cherry Springs Park Pa, Calhoun Park WV, and from home near Pittsburgh. Due to light pollution, home is primarily used for shaking down new hardware or software versions and if test image runs happen to turn out well, I process them. I am a spring through fall imager. Snow and cold hold me back in winter but someday – who knows.
Cherry Springs State Park in Pennsylvania is a special place for astronomical observers and imagers in the northeastern United States. In 2008, due to its isolated location and 2,300-ft altitude, it became the second recognized International Dark-Sky Association Dark Sky Park in the world. The Pennsylvania Department of Conservation and Natural Resources has developed the site for amateur observers with electrical pedestals, telescope pads, WiFi and even four enclosed observatories for rent. Albany, New York City, and Philadelphia are less than a 5-hours drive — making it a destination for amateur astronomers escaping the light domes from these cities. The site is popular enough with dark sky enthusiasts to host two star parties: Cherry Springs Star Party (CSSP) in the spring and Black Forest Star Party (BFSP) in the fall. See the Stargazing and Astronomy at Cherry Springs page at PA Dept. of Conservation and Natural Resources website.
Calhoun Park, West Virginia is located on a ridge in the unincorporated community of Mount Zion. The sparse population surrounding this 1,100-ft altitude site has contributed to the park being locally designated a Dark Sky Site. The park’s volunteer Board of Directors endeavors for it to become an official International Dark Skies Park. See the park’s Stargazing page for updates.
I met Al Nagler about 4-years ago at Cherry Springs during one of the star parties. He was stationed inside one of the large white vendor tents. I discussed with him my version of the Tele Vue-NP127is with an end ring of 4 attaching thumb screws vs the newer model with 3 and he indicated that the newer version could be purchased if needed. Al also mentioned – humorously – that the way the Starbeam has the black tapered end is because “he liked it.” Gotta love that spirit.
Currently, all luminance, red, green, and blue (LRGB) broadband filter exposures are 300-seconds while narrowband filter exposures are 1,000-seconds. Luminance is binned 1×1 while R, G, and B, are binned 2×2. For narrowband, Hydrogen-α (Hα) is binned 1×1, while Sulfur (SII) and Oxygen (OIII) are binned 2×2. I’m sure there are many alternate exposure formulas out there, but this keeps it simple to two numbers. The exceptions to this are star clusters – which are infrequent targets – I then half my LRGB exposures. The 660mm Tele Vue-NP127is focal length makes using an off-axis guider (OAG) easy. I have always been able to find a guide star and have the benefit of minimal, if any, flexure.
Meet the Tele Vue-NP127is APO Refractor.
The largest and fastest scope on offer by Tele Vue is the 5-inch, f/5.2, flat-field Tele Vue-NP127is. It is the ultimate incarnation of the Nagler-Petzval design (4-element/2-group) which continues our 40-year heritage of making exemplary multi-purpose refractors. The “Imaging System” scopes come with additional features to make imaging easier and more flexible without any compromise to visual observing. Imaging System features include: large rear group elements to maximize illumination, a 2.4″ focuser to allow those additional light rays to illuminate across 52-mm diagonal chips, a lockable, tilting end-ring to square the camera to the image plane if necessary, and 10:1 FocusMate dual-speed focuser for fine-focus. The focuser accepts the optional motorized FDF-2004 Focusmate Driver for vibration-free, variable-speed, electronic motor control. For automated focusing, it is compatible with Starlight Instruments Focus Boss II system.
Sky & Telescope’s review of this versatile photo/visual scope raves that “if you expect better from a 5-inch, f/5 refractor, you probably haven’t been living on this planet.” They also reported, “no focus shift when switching between standard red, green, and blue filters used for conventional tricolor imaging — a tribute to the TV-NP127is’s superb color correction.”
The focuser is built to carry 12-lbs / 5.4-kg of payload, so it can handle most any filter-wheel / camera combinations or the heaviest Tele Vue eyepiece with ease. With a 4° maximum visual field of view, using our optional 55mm Plössl or 41mm Panoptic, this scope can act as its own finder. The OTA has a captive, sliding, metal dew shield, and screw-on metal lens cover. It comes in a custom-designed hard-shell carry case with room for all standard accessories.
“There’s no such thing as an all-purpose optical system for astrophotography, but if you’re looking for a 5-inch f/5.2 refractor that can cover today’s 37-mm-square CCDs, then you’ll be hard-pressed to do better than the TV-NP127is,” is how Sky & Telescope concluded their review.
Over the years I have learned that simpler is better – in astrophotography as well as other aspects of life. So, for astrophotography, the past several years have focused on setup simplification. The main camera/filter wheel/off-axis guider/guide camera are combined and attached to the scope as one unit (simple). An electronics box, containing the power distribution hub/USB hub/focuser controller, along with connecting wires, attaches as one unit (simple).
Closeup: Frank’s Gear
In the image below is Frank’s Tele Vue NP127is (127mm, f/5.2, Nagler-Petzval) APO Refractor with Robo Focus motor replacing the left-side focus knob and electronics box on top. On the imaging end is the Atik 383L camera in the back behind an Atik Filter Wheel. On the side is an Atik Off Axis-Guider that holds an Atik 314E camera. All this equipment rides on a CGEM mount.
This electronics box contains a finder base, Robo Focus control box, USB Hub, and Power Block. “The box lid is kept on to minimize dew on the electronics. The only time the lid is off is when I use a red dot finder for alignment – which is very rare – after which the lid goes back on.”
See more photos of Frank’s gear on his Equipment page on SmugMug.
I have used several types of image capture software over the years. Currently, for capture, I use CCDciel to manage an entire night’s run. I love this software. Once set up and running, I only check in periodically which allows me to take a nap or, if I feel brave, tuck in for the night.
For image processing, I am now exclusively using Astro Pixel Processor (APP) for image calibration, stacking, combining channels, and Digital Development Processing. After APP it is Photoshop for everything else. In Photoshop there is a general flow to the processing but I have found that no image is ever 100% like another, so there is some customization and personalization to each image.
Did you observe, sketch, or image with Tele Vue gear? We’ll like your social media post on that if you tag it #televue and the gear used. Example:
#televue #np127is #ethos #jupiter
Do you want your Tele Vue images re-posted on Tele Vue Optics’ Social Media accounts? Use this hashtag for consideration:
#RPTVO
- Frank’s SmugMug site.
- Frank’s Facebook page.
- Tele Vue-NP127is on our website (mobile site).
