Ekos Polar Alignment Fix

Gary 5 minute read

After poor results trying out Ekos’ Polar Alignment helper module the other night I spent a little time looking over the indilib and Ekos source code.

To recap, last session I noticed Ekos was failing to wait for the scope to stop slewing before taking the 2nd polar alignment image resulting in variations of:

M27 & Guider Testing

Gary 3 minute read

A few nights ago I tried to use the Polar Alignment module of KStars/Ekos to obtain an accurate polar alignment without the need to spend time drift aligning. Ekos had other ideas though.

Polar Alignment

The way Ekos works is you slew the scope to a star in the south and then east as you would for a normal drift align. Ekos takes an image and plate solves using a local (or online) install of Astrometry.net to determine exactly where the scope is pointing.

Ekos then slews the scope 30 arcminutes in RA only and takes/solves a second image. It uses the result of those two images to calculate[^2] the polar alignment error. At least, that’s the idea.

iTunes IR Remote

Gary 2 minute read

I use a Logitech Harmony One IR remote to control my various home entertainment systems which includes a mac running iTunes[^1] Most of my smart playlists select tracks based in part on the ratings of each track. To help encourage myself to rate more of the tracks I’ve create a small utility called Iris.

The wonderful thing about Tiggers

Gary 4 minute read

It’s nearly Halloween and my family have been digging out Halloween decorations which is how a broken Tigger toy landed on my desk.

Opening the pumpkin and exposing the internal circuit/wires showed the source of the problem. Three of the power wires connected to the LEDs had snapped along with a battery ground wire on the original circuit board and both of the resistors each had a snapped leg.

Neutron Flux

Gary 1 minute read

Our first iPad game, Neutron Flux, is available on the App Store[^1]

Neutron Flux is a game of simple rules. Place atoms until you reach a cell’s limit, cause explosions/chain reactions and capture your opponent’s squares. Capture all the squares to win the game.

Page Turner Mk II

Gary 2 minute read

Using an LCD monitor + computer for sheet music display along with the first version of Page Turner has turned out to be a much nicer experience than struggling to page turn manually. The monitor and need for a computer is not the most convenient pairing though. An iPad on the other hand is portable and just about the right size for showing one page of sheet music[^1] and then there’s the touch screen for annotation. Unfortunately my Page Turner pedal, which is serial based, will not work with it.

It was time to make Page Turner Mk II, a USB device that plugs into the iPad’s camera connection kit and identifies itself as a USB keyboard device. It sends a page forward or backward keypress depending on which foot pedal is pressed.

MX716/7C and SXV 64 Bit CCD Drivers

Gary 1 minute read

Last year I switched over to a 64bit operating system and realised there were no 64bit drivers available for the MX716 CCD camera I use for astrophotography. Unable to pass up the opportunity to learn about windows driver programming I spent a bit of spare time creating two drivers for the camera (firmware loader and blockIO driver).

The driver supports both the original StarlightXpress software, AstroArt and MaximDL. In addition, the MaximDL universal firmware may be used (see installation instructions for details).

I’ve also created 64bit drivers for the newer Lodestar guiding camera and SXV USB2 range of CCDs. Both the SXV and older MX716 drivers are now available for download direct from the Starlight Xpress site.

My thanks to Terry from StarlightXpress for his assistance and openness on the SX hardware.

Page Turner

Gary 3 minute read

It’s about a year and a half since I bought a Digital Piano and finally started practicing daily. In that time I’ve progressed quite well and the pieces I’m able to play (albeit still at the late-elementary / early intermediate level) are finally starting to increase in length to a few pages.

This has brought about a problem I’d not considered up to this point that I’m sure plagues many pianists. How to turn the page without interrupting your playing. Given time I’m sure I could get used to reaching up and turning the page and make do with copying a few measures from the next page to get me to a suitable place to turn the page, but I’d rather not.

A product called the AirTurn provides a solution to this problem. However, as a hardware hobbiest I decided to roll my own. Using a Laptop or LCD monitor to display the scores in either Adobe Reader or Music Reader and a serial connected foot pedal to fire off a PG Down event.

RA Clutch Slippage

Gary 3 minute read

Back in 2002 when I purchased my first telescope, an 8” LX90, the first month or so of usage brought up a very frustrating problem. When slewing the scope to a new target it would suddenly stop mid-slew, yet the motors continued to whir. The cause was the RA clutch disengaging. Gotos were now ruined and after re-tightening the RA knob to engage the clutch I had to start the alignment process over again. Very frustrating.

I solved the problem after receiving some useful suggestions from the LX90 yahoo group, not a single clutch slip in nearly 7 years usage :) Earlier today I received an email asking about how I fixed the issue so I thought I may as well type it up.

CCD Image Processing

Gary 4 minute read

It has been a while since I’ve made an astronomy post, not because I haven’t had the scope out imaging, but because I haven’t been all that happy with recent results. My images have been showing a nasty central brightening that prevents fainter details being brought out in post processing.

Why is this a problem? Take a look at the image below of M51. I’ve stretched the data a little to emphasise the brightening. The problem is that in order to bring out fainter details in the galaxy or the lower magnitude stars around the edges of the image, the data levels need adjusting. Long before those stars are visible, the bright centre has spread across the entire image and ruined it.