From the Director





by Rex Parker, Director

Outcome of Voting Last Month. The Amendment and Expenditure both were approved by membership last month, as reflected in the minutes (in this issue). Thanks to all of you who participated. We’re now operating with a 7-member Board and working on the plan for the new astro video camera, discussed below

Coming Soon! – Game Changer in “Electronic-Assisted Astronomy” (EAA) at AAAP Observatory. Photos below: EAA screen shots showing deep sky objects as they look in real-time in the field without additional processing. See discussion of equipment and software below.

How the Pictures Above Were Made. EAA refers to near-real-time “live” imaging with relatively brief exposures (seconds) displayed on a laptop or PC monitor in the field or observatory. Such images don’t have the same quality as “real CCD imaging” that you see on the web and in magazines which use multiple long exposures (many hours in total) and extensiveand often tedious post-processing. But there’s almost no waiting, it’s happening right in front of you. The club began exploration of EAA a few years ago with the Mallincam color video setup at the Observatory, with great success. Of course, technology changes quickly. The newer CCD cameras are game changers: improved sensitivity, larger CCD sensor size, very fast download rates, small size and weight, and very low power requirements. This allows field use with only a laptop for power supply. Examples include cameras using the Sony EXview HAD CCD sensors such as the Sony ICX825 series. New software, usually camera-specific, is key to the near-real-time display of the RGB color images on the laptop. Software quickly aligns and stacks multiplebrief exposures, so that exact polar alignment is not needed and lightweight portable motor-driven equatorial and tracking alt-az mounts can be used with sucess. Truly a new game.

Recent tests by members have convinced me that this is where AAAP should be. At StarQuest and at the Observatory last fall I tested the Starlight Xpress Ultrastar-color, a CCD camera the size of a 1.25” eyepiece. The screen capture images above show the “real-time” display with no further processing beyond live align/stack/mean of 4 to 10 second exposures by Starlight Live software. The camera was used with these telescopes: (1) AAAP Observatory’s Mewlon-250 (10”), a powerful but “slow” f/12, 3000 mm focal length scope reflector telescope on a Paramount; (2) At StarQuest, with my Tak FS128 (5”), f/8, 1000 mm focal length refractor on a 25 year old Celestron GP mount only roughly polar-aligned.

The Famed Herschel Objects. While folks may have different astronomy observing interests most are keen to see the famous deep sky objects such as the Messier list. But what about the Herschel 400 list? The latter is renowned as an accessible subset of William Herschel’s 1864 General Catalogue of Nebulae and Clusters, the basis of the current New General Catalogue (NGC) as described by guest speaker Michael Lemonick in January. The Herschel 400 objects are all potentially visible at our latitude – they were first found by Herschel in England. My wife and I visited the Herschel house in Bath, England a decade ago. It was fantastic to see the mirrors and a remake of the telescope that William and Caroline Herschel used to discover Uranus and nebulae, on display in the very house where they lived and worked (photos below). The telescope mirror was speculum metal, an alloy of copper and tin. While our skies aren’t nearly as dark as Herschel’s in the 1700-1800’s, our equipment today is definitely better – especially when we bring EAA into the picture! How the Pictures Above Were Made. EAA refers to near-real-time “live” imaging with relatively brief exposures (seconds) displayed on a laptop or PC monitor in the field or observatory.

Board of Trustees Meeting March 26. We’ll hold the next board meeting at Peyton Hall on Monday March 26 at 7:30 pm. Among the agenda items will be a discussion of specific CCD cameras for EAA

This entry was posted in March 2018, Sidereal Times and tagged , . Bookmark the permalink.

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