Astro Pixel Processor – PekDar – Astrophotography Engineering

Astro Pixel Processor – Basic Tutorial (Step‑by‑Step Guide)

PekDar — Thu, 03 Dec 2020 17:22:56 +0000

The main goal of this Astro Pixel Processor tutorial is to provide you, with the ability to quickly stack photos using the APP program, in the shortest possible time with minimal the baggage of knowledge need. I share with you what I know. I have gained experience using the APP program on my own. Remember that each photo of collected lights is different and the examples below, will not necessarily work for your collected photo lights. You should always look for the optimal settings and solutions for each lights. Please, note that I am not the Developer of the APP (Astro Pixel Processor), but only I’m user like you. I don’t know answer to every question that bothers you. Nor am I any representative of the APP Developer or its publisher. APP provides flexible stacking algorithms compared to DSS, supports mosaics, gradient correction, and multi‑session integration. A great balance between simplicity and power. Why choose APP? APP stands out compared to other programs (e.g., DSS, PixInsight) thanks to: Flexible stacking algorithms (multi‑session integration). Support for mosaics and gradient correction.Intuitive interface and automatic calibration. It’s a great balance between simplicity and power – perfect for astrophotographers who want more than DSS without the steep learning curve of PixInsight. APP Preconfiguration Click on CFG button From the drop-down list, set the amount of RAM you want to allocate for use with APP. The rule is simple, more = better. After setting the desired amount of memory, click on OK and that’s it. Lights processing – ATIK Horizon CMOS color camera The Light files are made with “ATIK Horizon color camera” with the filter used in the optical path. We will be processing a photo from a single session so, the following settings of individual tabs are in the given configuration. Run the APP program (my version is 1.081). Shortly after starting a window will appear in which you have to enter the path, to the working directory. Preferably the same directory that contains Lights files for stacking. On the left side of the program window, under the tabs, uncheck two options: • Multi-Channel / Filter processing • Multi-Session processing In the Enter DeepSky object name: text box, enter the name of the object that was photographed. After selected files are loaded, the counter for Lights will change from 0 to the number, of files that we have indicated for loading. In my example, there are 89 files. 0) RAW/FITS ATTENTION! if your photo material was made with a camera, set pattern to supported. pattern set to supported turn off force Bayer/X-Trans CFA Click on the tab 0) RAW / FITS. It is very important to know the sensor type of the camera, on which the photos were taken. In the case of ATIK Horizon it is GRBG and such should be set for pattern from the list of available types. We enable the force Bayer / X-Trans CFA option, the other options are not changed. 1) LOAD Go back to the 1) LOAD tab and click the Light button to load the Light photo files. Notice the counter with status 0 to the right behind the buttons. In the file selection window, select the files you want to load and click the Open button. After the selected files are loaded, the counter for Light will change from 0 to the number of files, that we have indicated for loading. In my example, there are 89 files. At the very bottom of the program window, there is a preview of the list of loaded files. It is worth reading the description of each column – helpful and necessary information. Now repeat the process of loading files for the types: Flat, Dark, DarkFlat and Bias. You can skip all calibration frames or the missing type, then you should take into account that the quality of the photo will be worse. If you already have previously generated MasterFlat, MasterDark, MasterDarkFlat, MasterBias and BadPixelMap files for the Flat, Dark, DarkFlat and Bias file groups, that you want to use, you can load them now and skip the Master… regeneration process it saves a lot of time in the whole photo stacking process. WARNING! Remember that Master files generated from a given group belong to the Lights files photo session. The exceptions to this rule are BadPixelMap and MasterBias. 2) CALIBRATE Plenty of options available here, you can get a little overwhelming. We will be focusing only on a few specific options following my example. I think that the following description will be applicable in most cases of the collected lights files. Most options have a default value that we won’t change except for a few. Turn on: scale MasterDarkFlat scale MasterDark Now it’s time to generate Masters calibration files. Click on the create Masters & assign to Lights button. WARNING! – If you have already loaded Master calibration files, click the (re-) assign Masters to Lights button, this will assign the lights files to the calibration files. APP – Calibration frames options After creating the Master photos, you can see what they look like. This is very important. The quality of stacked the final photo depends on the quality of Master files preparation. In the file view list (at the bottom of the program window), you will see the Master files created. To view the mentioned files, just click 2x LMB on their name to load them to preview. Below is a sample of how my Master files look like. They are generally not bad and they are suitable as a calibration files for lights files. BadPixelMap – zoom 80% MasterDark – zoom 80% 3) ANALYZE STARS We do not change the default value. 4) REGISTER Most of the default options are set correctly and we will not change them. Let’s go to the next tab. 5) NORMALIZE Configure the individual options as described below. It is possible that some options, are already set by default as defined

M81 & M82 – A Study of Galactic Collision

PekDar — Sat, 25 Apr 2020 11:32:23 +0000

M81 and M82 – The Perfect Pair

In the constellation Ursa Major lies a pair of objects that serve as the “holy grail” for medium focal lengths. M81 (Bode’s Galaxy) and M82 (Cigar Galaxy) fit within a single field of view, offering an incredible contrast in structure. They are located about 12 million light-years away from Earth but are physically separated from each other by only 150,000 light-years.

This is my first photographic attempt to M81. I’ve collected a lot of photographic material (about 10 hours) but also a lot of it I had to removed due to windy nights and after the first pre-selection I had about 8 hours of photographic material. At the stage of stacking, another 30% had to remove of material remaining based on quality algorithm, which I finally stack together. At the last photo session I noticed that so far, each time I focused the image not well enough.

M81: The Grand Design

M81 is a textbook example of a “Grand Design” spiral galaxy.

The Core: The bright yellow center consists of old Population II stars. Deep within lies a supermassive black hole with a mass of 70 million Suns (for comparison: our Sgr A* is only 4 million).
The Arms: The blue spiral arms are home to young, hot stars forming within density waves.

M81 / NGC 3031 – Bode’s Galaxyy

Due to the coma around the frame, where M82 is located, I will have to plan a separate photo session for M82.

M82: Gravity’s Victim (Starburst Galaxy)

M82 looks completely different—like a tattered cigar. This is the direct result of a close encounter with M81 several hundred million years ago.

Starburst: Massive tidal forces from M81 “churned” the gas within M82, triggering a violent star formation process (known as a starburst). Stars are born here 10 times faster than in the entire Milky Way.
Red Jets: Images reveal “bursts” of red gas perpendicular to the disk. This is ionized hydrogen (H-alpha), driven into space by the stellar winds of thousands of supernovae.

The Advanced Challenge: IFN

The background around these galaxies is not perfectly black. It contains the Integrated Flux Nebula (IFN)—faint dust clouds belonging to our own Milky Way, illuminated not by a single star, but by the collective glow of the entire Galaxy. Bringing them out from the background requires dark skies and long integration times.

Source: https://en.wikipedia.org/wiki/Messier_81 , https://en.wikipedia.org/wiki/Messier_82 , https://en.wikipedia.org/wiki/NGC_3077

Composition: Astro Pixel Processor (Linux),
Processing: GIMP + plug-ins (Linux),
Lights: 5[h] – ISO 1000,
Flats, Darks, Bias.

M66 Group Leo Triplet

PekDar — Mon, 16 Mar 2020 15:35:31 +0000

A M66 Group Leo Triplet is a small group of galaxies about 35 million light-years away[5] in the constellation Leo. This galaxy group consists of the spiral galaxies M65, M66, and NGC 3628.

Source:
https://en.wikipedia.org/wiki/Leo_Triplet

M65, M66, NGC 3628 – Leo Triplet

Flats didn’t work out as they should, but I somehow corrected it in the GIMP.

M65, M66, NGC 3628 – Leo Triplet with crops

Photos taken during night at 14/15-3.2020 near Bielsko-Biała city.

Composition: Astro Pixel Processor v1.077-6,
Processing: GIMP v2.10.14 + plug-ins (Linux),
Lights: 57 x 180[s], ISO-800,
Flats: 24 ISO-800,
Darks: 15 ISO-800,
Bias: 20 ISO-800

NGC6541 & M25

PekDar — Sun, 05 Jan 2020 22:16:17 +0000

NGC6541 (GCL 86 or ESO 280-SC4) – is a globular cluster in the southern constellation of Corona Australis. It is estimated to be around 14 billion years old. 6.3 [mag]. Distance from Sun 24,5 tly.

NGC6541 & M25

M25 (IC4725) – is an open cluster of stars in the southern constellation of Sagittarius. The cluster is located near some obscuring features, with a dark lane passing near the center. M25 is at a distance of about 2,000 light-years light-years away from Earth and is 67.6 million years old. The spatial dimension of this cluster is about 13 light-years across.

NGC 6541 Source: https://en.wikipedia.org/wiki/NGC_6541
M25 Source: https://en.wikipedia.org/wiki/Messier_25

Photos taken on June 2019.

Composition: Astro Pixel Processor,
Processing: GIMP v2.10.14 + plug-ins (Linux),
Lights: 10 x 90[s] ISO 1000,
Flats: 40 ISO-1000,
Darks: 17 ISO-1000,
Bias: 20 ISO-1000