Herb's Astro and Optics stuff

This page last updated Sept 9 2005.

As of Dec 2004 my "Herb's Stuff" Web site is at Retrotechnology at http://retrotechnology.com/herbs_stuff/ . If that fails try "retrotechnology.net" instead of ".com". As of Dec 31 2004, my previous Web site at New Jersey Computer Connection http://njcc.com/~hjohnson/ may no longer be available. Check the "Herb's Stuff" reference page at retrotechnology.com or the .net equivalent for more information.

To email me, see see my ordering Web page for my email addresses.

I've been an amateur astronomer since about 1990. This page shows some of the things I've done, places I've visited to observe, and some of the local astronomy clubs I've been associated with. It's not complete or current, regretably.

My astronomy activities::

Got or gave a telescope for Christmas? Here's some advice.
Here's details on how I refigured an 8-inch mirror in 2003-2005
In 2005 I'm making a new mirror from scratch.
A Cookbook CCD Camera I built for amateur astronomy use!
Here's The Amateur Sky Survey (TASS) and the work I did with them, including some reports;
...such as some optical tests with the Orion nebula and Orion finder for the TASS group;
A picture of me and a GEM mount under renovation. The mount, not me.
A picture and info about a meteorite chip I obtained in May 1999.
Something about a local astronomy club, the AAAP of Princeton, NJ.
An astronomy club I have visited, the DelMarVa Stargazers.
Something about my current astronomy club, the NJAA of High Bridge NJ.
some astronomy books and related items I have for sale.

As my wife is a quilter, she convinced me to make a "simple" quilt in May 1999. I saw Jupiter, with its pastel bands in a black sky, as a good subject. This quilt measures about 13 inches square (the apparent short side is the camera's fault). My wife was pleased enough with the result that she showed it with her quilts at a local show of her quilt guild. The members thought it was a "great first effort". The next one will be bigger.

Meanwhile, I have other activities on this Web site: Check my Home page for links to other sections on Astronomy and Optics; Apple Macinstosh stuff; S-100 computers and 8-inch floppy drives; SGI, Sun and DEC equipment; some "odds and ends" computer stuff; electronic and other test equipment; and personal information.

Astronomy and Optics Stuff

Cookbook CCD camara

I built this digital CCD camera in 1995 for astronomical use, and I sold it a few years later. Thousands of amateur astronomers have built this model, offered as a book and circuit boards and a kit of parts.

GEM mount and author

Here's my German Equitorial Mount (GEM) and I'm standing next to it. This mount of brass and iron pipe was built in NJ, probably in the 1970's, and was previously owned by various organizations in Princeton. In 1998-99 I found an engineer, Jerry Avins, to help me restore the GEM. He cut a Delrin worm gear to drive the larger gear, which moves the mount to follow the apparent motion of the sky). And Jerry's set up the worm on a prototype platform with drive shaft and stepper motor! He and I designed the drive mechanics and some of the electronics to drive the stepper. I have an old 8-inch telescope to put on the mount, built in the 1930's. Eventually I'll either mount that tube on the mount, or I'll build something from my 12.5 inch f/7 mirror as a new telescope.

Meteorite chip

At the 1999 Rockland Astronomy Forum, I bought this bit of Gibeon meteorite. It weighs about 18 grams. The black area is the outside crust, with a little thumb-sized depression due to ablation during its fall. The edges are sharp and flat from cutting. Another photo shows the Widmanstatten pattern of fine crystalline line structure, revealed with an acid etch: a clear indication this is meteoric material. This is part of 18 tons of meteoric material recovered in the 1990's, from an old fall in Namibia. Pieces up to 1400 lbs in weight were recovered.

Local Astronomical Clubs & Observatories

The New Jersey Astronomical Association (NJAA) has been around for over 40 years. It has an observatory with a 26-inch telescope and dome, and a public meeting and storage facility, at Vorhees State park in High Bridge NJ. When I restore my personal Web site I'll have photos and commentary about recent NJAA activities, my own and others. The NJAA Web site is at http://www.njaa.org.

From time to time since 2003, I've attended meetings of the ATM (amateur telescope making) group of the STAR astronomy club, which meets in south New Jersey. Their ATM group meets at occasional intervals at sites sponsored by Gordon Waite. Check their Web site for details. A number of NJAA members work with that ATM group, which led to my interest there. In 2003-04 I'm working on an 8-inch mirror at that site.

[AAAP Obs.] Here's a 1998 interior shot of the Amateur Astronomical Association of Princeton's Simpson Observatory at a nearby state park just outside of Trenton NJ. Several club members are preparing the Observatory for winter operation. The telescope in the back is a 12.5 inch f/6 reflector (big mirror). (This scope is now at their new observatory in northern New Jersey. It was replaced with a Celestron C-14 and a Software Bisque mount.) The foreground telescope is a Hastings-Byrne 6-inch refractor (6-inch lens) that was built in the 1880's. Despite the flaky paint it is a good telescope, used in its time for critical observations of the Sun. (The original mount as pictured was replaced a few years ago, and the refractor was rebuilt, but it is still in operation today.) A Web site for the AAAP is http://www.princetonastronomy.org/ .

The Amateur Sky Survey

The Amateur Sky Survey (TASS) group is a collection of amateur and professional astronomers who are performing a sky survey of stars near the celestial equator. Their sky cameras were built by Tom Droege (DRO-gee) formerly of Fermilab. A new generation of sky camera and tracking mount, the Mark IV, was developed in 1999-2000, for more general sky survey work done subsequently. Discussion and planning is done over a maillist - some of the participants have never met personally! - and much of the work and dialog is archived on the TASS Web site in their mail archives and their "Tech notes".

In support of the Mark IV, in Nov 1999 I did some dark current analysis of Mark IV image files from Tom's #5 CD-ROM, distributed in late Oct 1999 by Tom. I also analysed coma and saturation in the early Mark IV disk #5 images. (That coma went away when they properly re-assembled their lens system.) I also chronicled their discussions of data compression of TASS star images, archiving devices for TASS star images, and discussions of Mark III time references and VCO rates.

One of my more comprehensive Tech Notes was #57, on Mark III sites and databases. It is a compliation of information about the Mark III cameras: who had them, who used them, what software they used, and what they did with the data. There are Web pointers to the host sites for each camera. I consider this a very useful Tech Note for anyone trying to make sense of what TASS was all about in that era. Other Tech notes from that period describe what was done with the data collected at that time. My involvement was primarily with the Mark III and early Mark IV development. I have a broken Mark III camera - one of the few not destroyed by time or weather! As of 2001 I'm not active in TASS.

See the TASS Web page at http://www.tass-survey.org , and work your way over to the "technical section" and then to the "TASS Tech Notes" to see the many TN's submitted by my TASS colleagues and myself.

In 1998 I used the 12.5 inch telescope of the AAAP to guide my 35mm Nikon FG camera and an Orion 400mm f/5 telescope for this 4-minute exposure of the Orion Nebula, using Kodak MAX (800 speed color) film. I evaluated the Orion telescope as a test optic for a CCD camera under development for TASS. The photo was taken about an hour after sunset, 7PM -7:30PM on March 16th 1998 with Orion near the meridian at about 45 degrees altitude.

Herb Johnson
New Jersey, USA
check this link to email @ me