Explore Scientific AR 102
Feb 09 2016 08:10 AM by phxbird
Review: davejlec's Paralellogram Mount
Feb 08 2016 09:26 AM by tlriedel
Annals of the Deep Sky, Volumes One and Two
Feb 08 2016 08:03 AM by twatson
Discovery 17.5” Split Tube Dobsonian Telescope
Feb 07 2016 07:20 AM by clay1022
REVIEW OF SUMERIAN OPTICS ALKAID 16” TRAVEL SCOPE
Nov 26 2015 03:38 AM by alexvh
Astrotrac TP3065 Pier Review
Nov 20 2015 06:03 AM by James Waters
Apo-tmosphere: Gutekunst ADC Review
Sep 23 2015 09:18 AM by pbsastro
Optolong LRGB Filter Testing and Comparison wit...
Sep 22 2015 11:41 AM by turbo399
Converting your telescope's RA drive from an open control system to a closed control system can eliminate the need for PEC.
If you look at an old star map of the late winter sky created 250 or more years ago, you'll find a huge, unfamiliar constellation dominating the sky to the south and east of Canis Major. That's Argo Navis, a behemoth of a constellation dating from ancient Greece that depicted the mythical voyage of Jason and the Argonauts as they searched for the Golden Fleece.
Whilst driving through the Tropic of Capricorn, 140 km north of Gaborone in Botswana, I stopped one day to look at the curious structure by the side of the road and was pleased to find it was a Solstice Machine.
Head outside this evening and take a look high overhead. If you live in midnorthern latitudes, you will find a lone beacon cresting near the zenith as the sky darkens. That's Capella, the Alpha star of the constellation Auriga the Charioteer.
Highlights: Comet Journal, Martian Landers, Meteor Showers, Fat Tuesday, Leap Day, Planet Plotting, February Moon. Focus Constellations: Cassiopeia, Cepheus, Draco, Ursa Minor, Ursa Major, Lynx, Cancer, Gemini, Orion, Auriga, Taurus, Camelopardalis, Perseus.
All in all, a relatively simple build once all the wiring plan was created and design was completed beforehand. I now have a long-lasting, durable power box with room to expand if needed although with a 140Ah deep cycle battery at its heart, that should not be necessary anytime soon.
The luminosity of a telescope, I. e., the brightness of its visual field, can be mathematically defined by the ratio between the light flux reaching the eye when the observer looks through the telescope and the light flux reaching the naked eye from the same target.
To simplify my dilemma, the scope needed to be portable, quick to set up, cheap; and oh yes, and I wanted it to track the stars. Sadly, I have no machine shop at my disposal, but, and there is a big but (no pun intended), I had more time than money.
This is not so much a review of the CGEM as a detailed analysis of a problem related to guided astro-photography and only seen in some samples of the CGEM. A visual user would never encounter this problem at all.