Showing posts with label GIMP. Show all posts
Showing posts with label GIMP. Show all posts

Tuesday, April 30, 2024

April 8 2024 Total Solar Eclipse (44-sec capture)

Why only 44 seconds instead of reported totality of 2 minutes and 35 seconds? Clouds interfered with and distorted the capture, eventually totally obscuring the corona after ~43 seconds. My entire recording was 2 minutes and 26 seconds, but the viewfinder showed only darkness from about 44 seconds till the end. The video shows real-time speed (~44 seconds), then half speed.

Eclipse Day Decisions Made For Better or Worse

I couldn't order the weather. It was fickle for a good amount of Texas, including my viewing site, Austin. Weather forecasts and updates seemed to constantly change. Inclinations to travel were tempered by fears of encountering vehicular multiple-dimpling and hail-caused car window smashings. Also, destinations required real time to reach; available time required for traveling eventually evaporated. We stayed put.

From hearing stories about past eclipse events. area population swelling and travel would be challenging for residents and visitors alike. Highways and smaller roads could result in no-gos from traffic overflow or collisions or combinations. News frequently broadcast alerts about having certified solar glasses, stocking up on food, ensuring full gas tanks, and preparing for hours-long departures afterwards. We took the advisories seriously.

I should have thought of using a tripod for my Canon IXUS 180 (PowerShot) camera. As much as I tried to hold it steady, it shook. After I truncated the recording from 2 minutes and 26 seconds, I manually aligned the frames using GIMP. The process was similar to how I aligned the October 2023 annular eclipse frames.

Article:"Partial Annular Solar Eclipse Oct 14 2023, Austin"
YT video ~35 sec): Side by Side Eclipse Views, Austin Area Oct 14 2023"

Another should-have-done was aiming the camera downward a few seconds before totality, turning it on and starting to record, then aiming the camera upward. I would have captured the timer beeper for start of totality. (I did manage to capture the timer's end-of-totality beep.)

GIMP and OpenShot Image Processing

In short, I used GIMP, with grid display to align the images in layer views. The task was much more difficult than October 2023 annular eclipse because of moving-clouds distortions and obscuring. Several times, the view transitioned from disk to arc to smudge, in different directions and varying focus qualities. Clouds! Consolation is that some of the corona was viewable, and we got no rain.

As for OpenShot, I had help with converting the clip to individual frames, then re-assemblling the edited frames into a view-stable disk-centric movie. Turns out that trying to use OpenShot to assemble the frames froze the tool. We used ffmpeg in a command window.

Extra Touches

Some features I hadn't tried ever, or in a long time:

  • I used some OpenShot's capabilitiese to crop, scale down, and move an inset movie of a kitchen timer.
  • I extracted about 50 seconds of audio in OpenShot, then opened and edited it in Audacity. I added it to the video, along with the image of the graph.
  • I created an outline circle to note the major visible prominence at 4 o'clock position.

If I Knew Then, ...

I discovered many of my actions generated a lot of heat before light. Glad to have learned shorter steps eventually. A thought kept me going for creating the video. I'd never think about processing another eclipse set of images. Not inclined to go to another eclipse site any time soon.

"Can’t get enough of the total solar eclipse or got clouded out? Here are the next ones to watch for" provides some years to consider next US eclipses.

The next U.S. taste of totality comes in 2033 when an eclipse brushes Alaska and Russia. And in 2044, one will cross Greenland and western Canada, touching swaths of North Dakota and Montana. ... An eclipse on the scale of Monday’s event won’t happen again until Aug. 12, 2045.

"Future Eclipses" provides some info in tables for future solar and lunar eclipses. Long haul to get there.


Want additional astronomy-themed articles? Click for "astro topic" search results in my blog. Related: Sky/Astronomy Items YouTube playlist

Saturday, December 30, 2023

GIMP-adding Newest Saturn to 3-Saturn .xcf File

My previous topic, "2-Saturn Composite, Anticipating Future Edge-on Rings" inspiration came from my curiosity about Saturn's upcoming rings edge view, anticipated in March 2025. Because of Saturn's position behind the sun at that time, however, we won't be able to view or capture images of it then.

That article includes basic Saturn info and resources. The video "2-Saturn Composite Image, GIMP Revisit" shows numbered steps for creating the composite comparing Saturn images taken 9/2/2021 and 11/22/2023.

This time around, the topic is about having found a GIMP-editable (.xcf) 3-Saturn composite with images from 2015 and 2018 as well as 2021, then adding the image from November. The video shows the steps in using GIMP for the process. Main GIMP tools for setups and usage are layers, measurement, grid, move, and draw. Saving and exporting are must-do's for successful outcome.

Want additional astronomy-themed articles? Click for "astro topic" search results in my blog. Related: Sky/Astronomy Items YouTube playlist

Thursday, November 30, 2023

2-Saturn Composite, Anticipating Future Edge-on Rings

We recently pic'd Saturn, then recalled another imaging session (from about 26 months before. I wanted to compare images, then create a composite. The 2-Saturn composite image shows Saturn on 9/2/2021 and 11/22/2023. The orientations differ, and the newer Saturn's set of rings angle narrower than the rings of the earlier Saturn. During the image creation process, I had became curious about when Saturn's rings might "flatten", maybe disappear from view.

I thought about the steps I used in my process. Having used GIMP recently, and PaintShopPro earlier, I decided to make a slide show of the steps.

 

Some Saturn Resources

To acquaint myself with my orb target, I ran across a few basic resources. NASA's "Saturn: Facts" provides good overview. EarthHOW's "7 Planet Saturn Facts: Beyond its Signature Rings [Infographic]" includes more details and tantalizing images, especially the infograph. "How long does it take Saturn to orbit the Sun?" states "approximately 29.46 Earth years, or 10,755.7 Earth days, to complete one orbit around the Sun". This site provides a nice list of q/a's. Saturn has an unusual feature besides its rings: NASA's "Saturn’s Strange Hexagon" explains "a bizarre six-sided hexagon feature encircling the entire north pole".

"Saturn’s Rings Will Temporarily Disappear From View in 2025" (published November 13, 2023) explained the rings' next "disappearing act".

In 2025, Saturn’s rings will be invisible from Earth for several months. ... Saturn’s rings are so thin that they seemingly vanish when viewed edge-on. And as Earth and Saturn travel around the sun on their respective orbital paths, our planet reaches this particular vantage point like clockwork, roughly every 13 to 16 years. ... the rings will disappear from sight in March 2025.

The following image represents three Saturn images, the existing duo, and a phantom representation for March 2025. The last image indicates planet tilt and edge-on rings. FWIW, Saturn is not in the night sky around that time frame, and the sun's angular alignment to Saturn WRT Earth's position endangers eyesight.

Want additional astronomy-themed articles? Click for "astro topic" search results in my blog. Related: Sky/Astronomy Items YouTube playlist