Comet 2020 Neowise (aka C/2020 F3 NEOWISE) was easily visible in the evening in the Northern hemisphere during the July 19 week end. While the kids were doing a bonfire, I did some DSLR pictures, at 200mm of focal and f/2.8, without bothering with an equatorial mount (most of my time was spent supervising the bonfireContinue reading “Comet 2020 Neowise”
Author Archives: Erellaz
Damselflies
Damselfiles (demoiselles) are smaller than dragonflies, and when at rest, they fold their wings over their bodies, unlike dragonflies who spread them open and flat. I found a few of them while visiting a creek in East Texas and took some time to do some Macro pictures.
Tiger Swallow tail
Wild life in the city is amazing. Yesterday a Tiger Swallow Tail butterfly graced us with its presence for a few minutes, in the middle of Houston. I took the opportunity to play with the Sony 70-200 f/2.8 and Sony A7RIII and improvised, a few pictures in my front yard, all hand held. In macro,Continue reading “Tiger Swallow tail”
Objects moving in the sky
When close to both their perhelion and to Earth, comets can have a fast motion relative to the background sky. This is also the time when they are the brightest. If using very fast optics (the C11 + hyperstar, at f/2 for 280mm of aperture is well suited), it is possible make a video ofContinue reading “Objects moving in the sky”
Taking a picture of the most luminous blazar flare ever recorded.
A blazar is an active galactic nucleus with a relativistic jet (a jet composed of ionized matter traveling at nearly the speed of light) directed towards the observer. CTA 102 is a blazar-type quasar discovered in the early 1960s in the constellation Pegasus. It is also one of the two great false alarms in theContinue reading “Taking a picture of the most luminous blazar flare ever recorded.”
Simeis 147, the Spaghetti nebula
Simeis 147, also known as the Spaghetti Nebula or Sharpless 2-240 is a supernova remnant in Taurus. It was discovered so late (1952), because it’s dim. I was curious to see what was possible on the low end from my site with the Borg 55 and a H-Alpha filter. So here it is. I haveContinue reading “Simeis 147, the Spaghetti nebula”
Orion H-Alpha mosaic
This is my first H alpha mosaic, using the Borg 55. It was acquired over the winter of 2018-2019, and one of the goals was to image the Barnard loop (Sh 2-276), a supernova remnant. The mosaic is centered on the horse head dark nebula (Barnard 33). https://erellaz.com/wp-content/uploads/2020/05/Barnard33.jpg
Colorizing old black and white pictures with deoldify
I was looking for a cool Machine Learning project, using Python, of course, and either PyTorch or Tensor Flow, since it’s what the cool kids are doing those days. I have also always had an interest in restoration of old pictures, and sometimes colorizing them, which is a very tedious & time consuming project ifContinue reading “Colorizing old black and white pictures with deoldify”
A visit of Cygnus the swan
After finishing the Cygnus H-Alpha Mosaic, I extracted & rotated the iconic objects present in the image, at various scale to best showcase them. The full scale mosaic can be downloaded from the link below, and it contains all the objects shown on this page. https://erellaz.com/wp-content/uploads/2020/05/Cygnus_final_Pixinsight-1.jpg
Processing the Cygnus Mosaic
Processing the 30 tiles Cygnus mozaic was a bit of a challenge. First there is the logistic of handling about 2,000 frames and then the Borg 55 f3.6 astrograph exhibits strong field distortion making the merge of the images difficult, particularly where the corners overlap. For each of the 30 tiles I ran the PixInsightContinue reading “Processing the Cygnus Mosaic”