In my last post, I described how to capture tack-sharp images with my refractor by filtering out blue light using a Wratten #12 filter. The question remained: How can I capture color without blue? The first thing to realize is that stars emit a continuum of colors from red to blue wavelengths. A red star …
Don’t be misled by deceptive marketing that promotes a refractor as “APO-like.” I fell for it because I am always looking for a good deal. Well, this deal didn’t pay off. In essence, I purchased an Achromat with ED glass. Frankly, I don’t know how much of an improvement the glass makes, but I recommend …
I’ve only owned refractors. In my opinion, refractors are great for lunar and planetary imaging, but I have also seen outstanding images taken by fast refractors. Lately, I have become smitten by reflectors, although I do not own one. One thing I like is the diffraction pattern produced by the secondary mirror assembly. I wanted …
WASP-3 is a 10.7 magnitude star 3 degrees south of Vega in Lyra. WASP stands for Wide Angle Search for Planets. It consists of two robotic observatories in Spain and South Africa: https://en.wikipedia.org/wiki/Wide_Angle_Search_for_Planets Exoplanet “b” was discovered in 2007. It is a Jupiter-like planet 1.3 times the size of Jupiter. It revolves around WASP-3 every …
V1053 in Hercules is 13th magnitude that varies around 0.9 magnitudes from crest to trough. One of my goals was to determine a minimum exposure needed to produce satisfactory results. Satisfactory is subjective but for now I think that the “60-second data” is acceptable. When I captured the image files I alternated between a 60-second …
I am now onto my third stepper motor in two years. The motor is part of my self-designed right ascension drive system with periodic error correction. When I designed the system I chose a specific stepper motor from an overseas manufacturer. I knew that one day the motor might need to be replaced so I …
The data that I presented in Part 1 was from a single session on April 23, 2020 however I also captured data on April 19, 2020 but unfortunately it suffered from poor tracking. Nevertheless it is still useful for demonstration purposes. Before I present the second data set allow me to briefly describe the software …
On October 6, 1923 renowned astronomer Edwin Hubble discovered a pulsating star in the Andromeda Galaxy which quickly led to the revolutionary discovery that M31 is a galaxy unto itself 2.5 million light-years away, and not a gaseous cloud of stars within our own Milky Way. I dipped into my archive of astro images to …
Today’s NASA Astronomy Picture of the Day (APOD) is a celebration of the 100th anniversary of astronomy’s Great Debate held at New York’s Museum of Natural History between Harlow Shapley and Heber Curtis. Shapley argued that the Milky Way was the size of the known universe and that the Andromeda Nebula (M31) was part of …
Photometry with your CMOS or CCD camera has always been and continues to be of great importance to science. There are many different types of variable stars. There are Cepheid type stars that are useful for measuring the distance to galaxies, and then there are Eclipsing types of which ‘GK Boo’ is one. The ‘GK …