Category: ATM
Camera at the Newtonian focus
My D70 is 5.5”x4.4”. That’s a coverage of 24.2in^2. A 13.1” mirror has an area of 134.78in^2. That’s a 17% obstruction. Even if I mounted the thing on a 5.5” disc, basically […]
Blue CR-1
Art asked if he could buy the blue CR-1 focuser that’s been sitting in my parts box. Until a day or two ago, I didn’t have a use for it. But now, […]
Trixie's on the way
I bought a 13.1” f/4.5 mirror and matched 3.1” secondary today for $400. It used to be a Coulter red-tube Dob, but I’m just getting the mirrors. They will turn into the […]
LCD test patterns
http://www.lagom.nl/lcd-test/
Gemini NMEA 0183 GPS info
http://www.psychologie.uni-regensburg.de/Zimmer/trafficresearch/NMEA0183/index.html http://home.mira.net/~gnb/gps/nmea.html#gprmc According to the Gemini manual, pp.85, “Gemini requires only the “Recommended Minimum” (RMC) NMEA 0183 sentence to be sent,” This is: $GPRMC,225446,A,4916.45,N,12311.12,W,000.5,054.7,191194,020.3,E*68 225446 Time of fix 22:54:46 UTC A Navigation […]
RE: Nikon Support
Hi Art, Yep. This is the gizmo I built myself. The Cercis one came out about a year later… I shoulda gone into business. J —- Original Message —- From: art.morton@worldnet.att.net To: […]
FW: [The Ek's Files] Comment: "USB For Your Digital Setting Circles"
Hi Jimbo, Someone posted a question about your digital setting circles USB conversion on my blog. Would you mind going over to my blog (blog.eksfiles.net) and posting a reply? Thanks – Dave […]
Re: DSC circuit – USB conversion?
Hi Jim, Glad everything’s working. Thanks for the report. BTW, I just finished revamping my digital setting circles web site and linked it to my blog. I posted some information about the […]
flat field schmidt camera from SN6
http://www5f.biglobe.ne.jp/~kztanaka/flatschmidtcamera.html
RECENT UPDATE
Polar Alignment Calculations
Here’s a page that derives Polar Alignment Calculations. (update 5/2020: the original site is gone, so I found the text on Wayback and am inserting it below. This is by the original […]
Gear / Observatory / Telescope
Special Guest Star takes the mount at Hilltop O
The Astro Jedi needed somewhere to store his light sab—- I mean, bucket, and I was only too happy to accommodate him. I have decided that I need to come to a […]
General / Maintenance / Observatory
Dome shutter is motorized again!
I finally decided to bite the bullet and fix the shutter motor. Things went sideways last winter, and I’ve been opening the shutter manually (and tying it shut with rope, so we […]
Trixie 2017 – tube mods
I finally got around to cutting the MTA-UTA tubes to length; the only eyepiece that would come to focus with the focuser spacer in place is the Televue 55mm Plossl. If I […]
MOST COMMENTED
Observatory
Observatory 2.0 – Time has come today!
General / Maintenance
First Light, a deeper look
Mount / Observatory / Telescope
Observatory 2.0 – Result!
Observatory
Observatory 2.0 – The Pier goes in
Gear / General / Maintenance
Martin Farmer Wormblock installation notes
Deep Sky / Long Exposure Photography
NGC2244, The Rosette Nebula
Deep Sky / Long Exposure Photography
Another beautiful night.