My Other Telescope is an 8.4 Meter - Part III: Polishing
May 08 2019 11:24 AM by Gork
I've started writing about this aspect of fabricating the world's largest monolithic mirrors a number of times. Each time I get to about ten pages before I realize how truly complex this phase of fabrication is. So, I am going to assume, for the sake of this account, that everything works as planned and there are no side tracks. That won't be true, but if I tell the real story, I'll never get done.
Filter Comparison For Imaging Broad Spectrum Objects In Light Pollution Areas
May 07 2019 12:03 PM by JTYoder2017
The primary purpose of imaging with a filter in the city is to mitigate light pollution and help suppress the noise so that the signal of the target object becomes easier to identify. This is rather easily achieved for nebula type objects that emit at very specific wavelengths but much more challenging to accomplish for full-spectrum sources such as galaxies and globular clusters. Cutting down on city glare is becoming even more challenging as city lighting transitions from Mercury type lighting that emits at defined wavelengths to LED lighting that generally emits broad spectrum lighting.
My Other Telescope is an 8.4 Meter: Part II - Casting
Apr 14 2019 12:48 PM by Gork
How do you create the world's largest monolithic optical mirror? As the saying goes, “One bite at a time.” It is a unique process in that it is entirely linear. No aspect of the process can be done in parallel since each step is entirely dependent upon the preceding step.
CEM25P - not overloaded but won't rotate clockwise
sonshadowcat - Today, 07:53 PM
A question about setting the grey/midpoint using the "Levels" tool
descott12 - Today, 07:43 PM
CCD/CMOS Astro Camera Imaging & Processing
EQM-35 and Explore Scientific AR102(doublet) - first contact
Sp0nG3Bo8 - Today, 06:57 PM
interstellarum Deep Sky Guide Desk Edition
Feb 03 2019 01:09 PM by Ray Cash
I’ve long preferred to have images—and/or drawings--of deep sky objects near my atlas, observing list, and, of course, my telescope. David J. Eicher’s The Universe from Your Backyard (1988) was an early, well-loved companion of mine, as was Burnham’s Celestial Handbook. So was the self-published 1994 John C. Vickers’ Deep Space CCD Atlas: North (and South). Vickers’ CCD atlases are images only, and rather primitive ones by today’s standards; but the atlases were not meant to be a compilation of ‘pretty pictures’; but rather a source of black and white images of interesting deep-sky objects that amateurs might want to hunt down with their warm, moist eyes, or sub-ambient-temperature imaging equipment. Enter the above masterpiece!
Chronicling the Golden Age of Astronomy: A History of Visual Observing from Harriot to Moore by...
Feb 03 2019 10:09 AM by Piechowski2
Chronicling the Golden Age of Astronomy: A History of Visual Observing from Harriot to Moore is a good-read for “we stargazers” and telescopists of a mellowed age. As winter approaches, I can imagine myself re-reading the hard cover version of this book, sitting in my soft recliner, snuggled into a warm throw with my dog on my lap and a steaming cup of hot chocolate or tea on the lamp stand alongside, as the snow drifts down or as the bright stars of the winter constellatory asterism appear outside my window.
Omegon Mini Track LX2 Review
Feb 05 2019 10:27 AM by project nightflight
The Mini Track LX2 is a small camera tracker that provides 60 minutes of tracking time. It was developed by Italian astrophotographer Christian Fattinnanzi and is distributed by Omegon. The device stands out among the other available sky trackers, since it is driven by a mechanical clock that needs no electrical power source. Besides that, it brings another innovation: To compensate for the camera weight, it features a spring mechanism that helps to stabilize the tracking rate.
Review of the APM 152 ED serial number 245
Dec 24 2018 12:42 PM by hfjacinto
So here are my thoughts. No matter how much you paid for a premium triplet, on most objects the 152MM can keep up with it. If you want to see no false color and need your ego stroked because the scope is not expensive, don't buy the APM. Get a TAK/TEC/AP, you'll feel better about yourself. If you consider the value, this scope is just an excellent buy. It’s like the EON version of the SW150. You get a better focuser/case/sliding dew shield/rings/ and a much prettier scope.
THE BURGESS 24MM MODIFIED ERFLE & 10MM ULTRAMONO
Dec 24 2018 12:04 PM by wapaolini
The Burgess 24mm Modified Erfle and 10mm Ultra Monocentric eyepieces are relatively new offerings from Burgess Optical. The Ultra Monocentric has been long promised so nice to see it finally coming to fruition.
APM 140mm DOUBLET APO REFRACTOR
Sep 10 2018 08:44 AM by Larry Carlino
Some two dozen observing sessions and direct comparisons with instruments of known quality have convinced me that this APM 140ED is indeed an excellent telescope. It is well built, nicely finished, and it boasts very fine optical quality. In addition, its relatively light weight and short tube length allows the effective use of a mid-size equatorial or alt-azimuth mount. It has almost the punch of a 6-inch refractor in a package that is clearly more portable.
Comparison of the Boltwood II and Sky Alert Cloud Sensors
Jun 09 2018 06:42 AM by theastroimager
This review is a side-by-side comparison of the Boltwood II Cloud Sensor from Diffraction Limited/Cynagon , and the SkyAlert Cloud Sensor from Interactive Astronomy. Both units were purchased new by the author. The sellers were not made aware that I would be doing a review of their products, so no temptation was held to send me anything other than a typical unit.
May 05 2018 10:14 AM by astrodoc71
I would highly recommend this site for anyone who wants to image targets that can only be seen or optimally seen in the Southern Hemisphere. The cost is not prohibitive and the fast optical system makes it possible to obtain enough quality data in a reasonable time frame. The seeing at this site in Chile is excellent, and the resolution and image quality obtained make it well worth the expense, not to mention the excitement of seeing these amazing objects which we cannot see from Northern lattitudes! The user interface is very simple and customer service is superb. While you will have to throw out some subs like we all do at times, these will not come at additional cost. Best of all…they add 20% to your initial deposit if you are a CN member!
MONO & BINO VIEWING WITH THE BAADER MORPHEUS 17.5MM EYEPIECE
Mar 22 2018 11:24 AM by wapaolini
Baader markets their Morpheus line as “high-end” 76° apparent field of view (AFOV) eyepieces designed for visual / photo / video functions that can exploit the capabilities of the finest telescope optics. The eyepieces have a optical design that utilizes 8 lenses in 3 groups and includes the use of 3 low dispersion ED elements and 1 Lanthanum element. With the introduction of the 17.5mm, there are now six eyepieces in the line including 14mm, 12mm, 9mm, 6.5mm, and 4.5mm. All eyepieces can be used in either 1.25” or 2” focusers without adapters. The Morpheus line touts a rather long list of features and comes packaged with multiple accessories.
The Eye of the Flak (Das Auge der Flak)
Dec 07 2017 02:46 PM by Micah
It is a rare and wondrous thing when your hobby and passion leads you to a place where you find yourself driven to pursue discover ever deepening levels of historical and technical detail of a subject and it leads to newer discoveries. It's even more satisfying sometimes when you even uncover information once thought to be lost forever to the ravages of time and a world war. A new publication, "The Eye of the Flak" by Dr. Peter DeLaet and Francis Vermeire, is just that.
COMPARING THE MASUYAMA 25MM 52°, 25MM 65°, AND 26MM 85°
Nov 24 2017 09:39 AM by wapaolini
The modern incarnation of the Masuyama eyepieces seems to have carried forward their excellent reputation for providing high apparent contrast views. Indeed, for the globulars and nebula observed the Masuyama 85° quickly became my favorite during the testing, showing them brightly, richer in details than the other eyepieces, and with the largest contextual TFOV.
BRESSER 4 Inch f 4.5 AR 102XS Refractor visual observers’ REVIEW
Nov 24 2017 09:41 AM by TimVerst
For me, the 102SX is a solid, wide/rich-field travel scope. I’ll pimp up the finder-scope and dew shield, making this one a keeper.