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On 11/19/2020 at 2:48 AM, DB said:

Are the stacking apps using super-resolution techniques? I first read about those when looking at papers from NASA where different orbiting imager data was being composited. Coincidentally, this was Mars imagery.

Must have been mid 90s.

 

The term "super-resoltion techniques" is not one I'm too familiar with but my understanding is that it includes a whole bunch of different techniques. 

 

Stacking increases the signal to noise ratio... it doesn't change the pixel count but you do get a clearer picture.  The term "stacking" actually dates back over 100 years when images were captured using photographic glass plates.  They would literally stack the glass plates on top of each other to improve the image.

Another technique that I sometimes use is drizzling the data.  I use it mostly on images taken with the little 70mm refractor to recover.  The combination to pixel size and the short focal lengths leads to under-sampled data.  Drizzling the data combined with dithering the scope between captures recovers lost detail.  Both drizzle and dither were developed by NASA for hubble.  If I image with my 8" SCT, I'm actually over sampled a little bit so there is nothing to be gained from drizzle.

During post processing, I will usually use deconvolution which helps undo some of the distortions caused by the atmosphere. 

With the planetary imaging I do.. I'm stacking frames from a video and I did use drizzle.

It's fun stuff.  I find astrophotography to be nice blend of science, technology and art.  The perfect hobby for me :)

 

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Thanks for the compliments guys.  We've had an amazing string of clear nights.  Here's another I finished recently.  This is the soul nebula.  This is a false color image using the Hubble palette.  Taken with my 70mm refractor.


C66nTKs3i_5I_1824x0_O3Qyqi6r.jpg

Edited by JamesR
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10 hours ago, JamesR said:

Thanks for the compliments guys.  We've had an amazing string of clear nights.  Here's another I finished recently.  This is the soul nebula.  This is a false color image using the Hubble palette.  Taken with my 70mm refractor.


C66nTKs3i_5I_1824x0_O3Qyqi6r.jpg

Again, I'm amazed at the quality of pictures available to amateur astrophotographers. The colors and 3d-esque nature would give the finest research telescopes a run for their money just 10 or 20 years ago.

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Great images JamesR!

 

I recently went out to try capturing Comet Erasmus but being in the city and the weather lately isn't conducive to seeing it even with a telescope. 😅 So still no-joy for me.

 

I'll try to capture M42 this long weekend. If I don't get lazy hahahahaha

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"hahahaha"...

A competing supervillain has emerged with superior astrophotography, and you're cracking jokes about slacking?

The world doesn't dominate itself, and there is no second place in the race of astro-supervillainy!

If the unruly citizens of Metro Manila dial the Bortle scale to eleven, there's only one reasonable cure, and you know it.

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And just in case that I need to spell it out: First strike with EMP, then seizing control of the major powerplants, and goon squads to smash flashlights and generators.

Then, 16" silveriodide cannon batteries to prevent the air from fogging up.

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7 hours ago, Ssnake said:

A competing supervillain has emerged with superior astrosurveillance, and you're cracking jokes about slacking?

FIFY

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Super-resolution is a statistical technique that takes a lot of images of a single scene and effectively uses the "jitter" between images to extract additional information. The way it typically works is to align the images onto a higher resolution grid than any individual image. It then generates a simulated "original" image that provides the best fit to all of the sub-pixel aligned images that were used as inputs.

In some ways, it's like stacking but uses "that one neat trick" to extract more information. For example, years ago I used a cheap flatbed scanner with a 600dpi resolution to scan a £5 note. I then used a command-line programme called "ALE" for "Anti-Lamenessing Engine" to produce higher resolution versions. It was extraordinary how much resolution could be pulled out of the "slop" in the scanner belts. The results were credibly 1200dpi, using about 30 scans.

This was very processor intensive, particularly the alignment step.

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On 11/27/2020 at 11:05 PM, DB said:

Super-resolution is a statistical technique that takes a lot of images of a single scene and effectively uses the "jitter" between images to extract additional information. The way it typically works is to align the images onto a higher resolution grid than any individual image. It then generates a simulated "original" image that provides the best fit to all of the sub-pixel aligned images that were used as inputs.

In some ways, it's like stacking but uses "that one neat trick" to extract more information. For example, years ago I used a cheap flatbed scanner with a 600dpi resolution to scan a £5 note. I then used a command-line programme called "ALE" for "Anti-Lamenessing Engine" to produce higher resolution versions. It was extraordinary how much resolution could be pulled out of the "slop" in the scanner belts. The results were credibly 1200dpi, using about 30 scans.

This was very processor intensive, particularly the alignment step.

That does sound very similar to the Drizzle option in stacking.  

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Here's another image.  This is the Rosette nebula.

I've been experimenting with narrowband imaging while using a one shot color (OSC) camera. 

Normally you would use a monochrome camera for narrowband imaging.  Color cameras have a filter called the bayer matrix.. works great for color photos on earth.. but its less efficient for astroimaging because only 25% of the pixels are used for red, 25% for blue, and 50% for green.  An Ha filter will block all light except a narrow band of red light.

Recently multi-band pass filters have come out.  One of them passes Ha and O3.  The red pixels are picking up the HA and the green and blue pixels are picking up O3 (O3 is a greenish teal color).  This helps a lot with the inefficiency of a color camera.  I also use a separate S2 filter.  S2 (Ionized sulfer) also emits red light, so using this filter alone only hits 25% of the pixels.  Just means more integration time.

 

s8f25TxJTXpE_1824x0_O3Qyqi6r.jpg

Edited by JamesR
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On 12/2/2020 at 2:42 AM, JamesR said:

Here's another image.  This is the Rosette nebula.

I've been experimenting with narrowband imaging while using a one shot color (OSC) camera. 

Normally you would use a monochrome camera for narrowband imaging.  Color cameras have a filter called the bayer matrix.. works great for color photos on earth.. but its less efficient for astroimaging because only 25% of the pixels are used for red, 25% for blue, and 50% for green.  An Ha filter will block all light except a narrow band of red light.

Recently multi-band pass filters have come out.  One of them passes Ha and O3.  The red pixels are picking up the HA and the green and blue pixels are picking up O3 (O3 is a greenish teal color).  This helps a lot with the inefficiency of a color camera.  I also use a separate S2 filter.  S2 (Ionized sulfer) also emits red light, so using this filter alone only hits 25% of the pixels.  Just means more integration time.

 

s8f25TxJTXpE_1824x0_O3Qyqi6r.jpg

Edited at 02:43? 

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On 12/3/2020 at 4:05 AM, Rick said:

Edited at 02:43? 

Well... what time of the day did you think I worked on my hobby?  lol.

 

Probably fixed a grammar mistake.  For some reason my proof reading abilities improve after clicking "submit reply".

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9 hours ago, JamesR said:

Well... what time of the day did you think I worked on my hobby?  lol.

 

Probably fixed a grammar mistake.  For some reason my proof reading abilities improve after clicking "submit reply".

Lol, I know what you mean 😲

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10 hours ago, JamesR said:

The CEM25s replacement:

 

https://www.ioptron.com/product-p/c26a.htm

Indeed! I was informed about it yesterday by my friend in the industry. I am going to order that once it is available. SO EXCITED!

I recently purchased an ASI224MC astrocam. I'm just waiting for a few more stuff and hope I could take photos of the Jupiter-Saturn conjunction. I hope the weather cooperates hahahahaha!

Only the mount is the missing piece. Filters etc will follow. :D

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