John Duchek's Page -Welcome

I am constantly updating, so watch for changes.....

Screenshot of eyepiece selection software
Eyepiece selection software calculates the % light lost for your pupil size and various telescope/eyepiece combinations.  This software is available on this site with versions for Windows, Linux, and Mac for free.  Also available is a pdf explaining how you can turn your 8" telescope into a 3" telescope with the wrong combination. 
 Links to weatherstations:
Carrizozo/Nogal, NM Weatherstation (Weather Underground)
Carrizozo/Nogal, NM Weatherstation (NOAA)
Carrizozo/Nogal, NM Allsky Cam

Concord/Sunset Hills, MO Weatherstation (Weather Underground)

Links to Linux OS Astronomy Versions:
Astronomy Linux - An amazing amount of linux astronomy
software, bootable from CD, or HD installable

Distro Astro - Linux Astronomy Software with some
 preinstalled windows software thru 'wine'

John's Pictures (on Flickr)-main page:
The Lunar 100 (all but 2, so the Lunar 98)
Hi Resolution wallpaper (1900x1200 approx)
2014 Timelapse, 2015 Timelapse, 2016 Timelapse, 2017 Timelapse

GPS video inserter project
3D Printed Newtonian OTAs
Cloud Detector (Transparency Measurement)
Technique for taking daylight moon photos
Lunar Meteor Detection


Below are the graphs of the cooling study on my 9.25" Celestron SCT. On the left is the curve of the uninsulated tube.  On the right is the insulated tube.  The insulated tube does a better job of keeping the whole OTA at an uniform temperature throughot the evening.  The uninsulated tube has the tube cooling at a faster rate than the interior of the tube
 Old talk LO Impress file downloads -
Files available:
3D Printer Filaments - 2018-10
Aging Pupils - 2011
Getting Started in Astronomy (2 nights)
Basics of Observing and Photographing the Moon
Lens Experiments
Moonlight Madness (light pollution)
Lunar Challenges (LC)
Shooting with a Canon