#PORTABALL318

 1. From under UTA with (L to R):

A. 3D printed Secondary Mirror in Snap-on rigid protective dust cup (bottom).

B. 3D printed oversized starpiece in the focuser for RLC/BRLC (laser collimator) dual-side projection screen with Cheshire center hole. 

TBC.

Orion 70mm Multi-Use Finder Scope

Just would like to share my impressions with this simple purchase.

At $100 it's somewhat overpriced for what it is indeed, as at the close inspection I have figured it's just the front piece of the Orion's 70mm binoculars plus the 6 adjustment screws shoe mount stalk and some threaded adapters. But overall it might worth it in the long run.

Internet of Things for amateur astronomy.

or The ultimate Telrad / QuInsight USB Power / Blinker Mod

Every light-producing telescope sighting device for astronomy use could benefit from the so called "Blinker" feature, which helps the observer to maintain the eyes darkness adaptation as much as possible during the telescope pointing flow with that type of finders simply reducing the light exposure. That allows to point with such a device using much fainter stars than with the reticle constantly shining into observer's eyes.

I had that "blinker mod" implemented over a decade ago using the trivial LM555 timer IC for my Telrad (you can easily google for that circuit and Telrad integration guides, there are plenty online). But as I have recently acquired the more advanced collimator sight the QuInsight I decided to make a more advanced blinker as well. But it turned out so advanced that I see it frankly opening the IoT era in amateur astronomy!

TPM Telrad Pattern Matching

Another writeup on the subject which is so trivial that it deserves a detailed explanation! How to use the Telrad properly? Many folks using it just as a glorified red dot finder. Which is sad to see knowing its potential rivaling even most advanced GoTo systems... But let's start from afar with the most frequent question a beginner or mature amateur astronomer is constantly concerned about: How to point a telescope to the invisible for naked eyes deep-sky target? I mean, in a reliable way? [the write up is still under development]

Photo by Guillermo Ferla on Unsplash

I bet you have heard dozens of answers to that already. After asking that question for over 40 years myself and trying what others doing to solve that problem I have finally got the definite answer: the TPM. Which stands for "Telrad Pattern Matching".

QuInsight the Telrad successor

QuInsight is the newest telescope pointing device leveraging the collimator principle similar to the Telrad. It has been designed and manufactured in 2019 by Rob Brown. Rob has a background in Optics engineering and owns a 3D printer which he is using to produce components of Quinsight.

I believe the QuInsight design is the best thing happened to the Telrad idea in the past 40 years (since the Telrad invention).

Dob Dolly. Furniture dolly mod to carry 12" Dob.

This is a really trivial construction which I've assembled in like 15 minutes from the scrap at hands to haul my Zhumell 12" pre-assembled to the other side of the high-rise multi-apartment building I'm living in (as well as to the roof in two runs). I'm observing from home right on it. It turned to be a very sturdy, mega-convenient, and fun to use system.

I think the image is selfexplanatory but folks from one of the forums begged me to share details anyway, thus they are under the cut along with all of the benefits list.

Time left before the sunset

This is the old boy scout method of determining the time left until the sunset (or elapsed after the sunrise) "manually".

And here is how I have it criticized for my backpacking group folks: