Linux Panorama
Panorama Tools are a collection of open source programs to blend multiple pictures into a single panoramic image. It can also create 3 dimensional (3D) pictures from 2 or more stereoscopic images. The tools work on Windows, Mac OS X, Linux and BSD. Another GUI interface for rtlpower. Similar in function to RTL Panorama. SDR-J (Windows/Linux) (Free) (Related Post) - DAB SDR-J. SDR-J is a free program that is split into two different programs. There is the SDR-J DAB/DAB+ receiver program and the SDR-J FM decoder program. The DAB decoder is the most popular of the two.
Astrophotography is closer to science than art, and there is no such thing as “getting it right in camera.” This means you cannot simply point the camera at the sky and snap away.
In astrophotography you cannot avoid post processing your images, so stacking and editing your images serves three main purposes:
- Reduce noise and deal with light gradients and vignetting.
- Improve signal to noise ratio.
- Reveal the faint details in the image.
Image stacking is the technique used to improve the signal to noise ratio, and it is the only noise reduction method that will boost the image details rather than smear them out.
In this article, we will discuss some of the most popular software available for astrophotography image stacking.
Note: Don’t miss the detailed video at the end of this article, It was created to help show you how to quickly start using some of the stacking software mentioned in this article.
Click here to skip to our Image Stacking Demo Video.
What Does Stacking Photos Mean?
The concept behind image stacking is simple, but to appreciate how it works, there are a couple of things we have to consider:
- A stack can be visualized as a pile of images all stacked one on top of the other;
- Each digital image is formed by a set of pixels, all having a certain value: dark pixels will have a lower value than the bright ones;
In the simplest form of image stacking, the pixels values for all images in the stack are averaged to produce a single image.
What is the purpose of stacking photos?
The result is a single image with improved signal to noise ratio, i.e., with better details and lower (random) digital noise and better details.
The scheme below illustrates the concept.
If the considered digital noise affects the pixel values randomly across the stack, then the result of averaging the stack is that the random component of the noise to the pixel value is significantly reduced.
ISO noise and Luminance noise and Chrominancenoise are examples of digital noises that are random.
The image below shows a real-life example from stacking 30 images from my Sony RX10 bridge camera taken at ISO 6400. As you can see, the original images showed a greater deal of noise (grain) than the stacked one.
The More Images You Stack, The Better
The more images you stack, the cleaner the resulting images are, as shown in the comparison below.
While Image stacking creates a cleaner image, it often softens the image: digital sharpening techniques are then used to recover sharp looking details.
Finally, bear in mind that the progression of image quality is not linear.
If stacking 4 images improves the image quality of 50% respect what you got by stacking only 2 images, to improve a further 50% the image quality from stacking 50 images, you may need to stack 300 images or more.
Image Stacking And Movement
If nothing moves between shots, like in the previous real life example, implementing image stacking is very simple: just group the images and average them to smooth out the noise.
With a moving subject, grouping and averaging the images will not only smooth out the noise, but also the subject itself.
This is the same principle for which long exposures of passing traffic and crowd result in a street image without cars nor people.
This effect is amplified with the number of images used, and the moving subject could simply disappear from the stacked image.
To resolve the issue, you have to align the images based on their content before stacking.
Due to image alignment, you may have to trim the edges of the stacked image to get rid of artifacts, but your target will not be lost.
Note that while in theory you can stack images of a static scene taken with the camera on a tripod, in reality, those images will probably differ at the pixel scale due to micro-movements. It is always beneficial to align the images before stacking.
How To Shoot For Exposure Stacking Your Images
Image stacking can be done with any camera and even camera phones and with images in both RAW and JPEG format.
Nonetheless, some things can be done to improve the final result:
- Lock the focus, so that the camera will not hunt for it between images. This will also help to keep the focus consistent through the shooting sequence.
- Keep the same settings, in particular shutter speed, aperture, and focal length: you don’t want to change the camera field of view during the sequence, nor the brightness of the images or the depth of field.
- If you are shooting on a tripod, disable image stabilization. If you want to shoot handheld, do so only for short sequences at very high shutter speed.
Image Stacking In Astrophotography
Related:Astrophotography Software & Tools Resource List
As said previously, image stacking is a standard technique implemented in any astrophotography editing workflow for,
- A star field from a fixed tripod.
- A deep sky object from a tracking mount.
- The Moon handheld.
- A starry landscape from a fixed tripod or tracking mount.
Every astronomy image will benefit from image stacking.
List Of Photo Stacking Software For Astrophotography
Here is a list of software used in astrophotography for image stacking.
Adobe Photoshop
Complete Image Editor Commercial – Subscription Plan Photography Bundle $9.99 / Month Mac OS X, Windows
Pro
- Versatile
- Available for Mac and Windows
- In bundle with Adobe Lightroom CC, Bridge, Camera Raw, and web space
- Many action packs and plugins available for astrophotography
Cons
- Subscription Plan only
- Can’t be used to calibrate light frames
- Stacking capabilities are somehow limited
If you are interested in photography, chances are you know Adobe Photoshop is the standard in the industry and does not need introductions.
With Adobe implementing a subscription plan for their applications, if you are using Lightroom CC for your everyday photography, your plan subscription will also include Photoshop CC and Bridge CC.
And for astrophotography, Photoshop is what you need. Lightroom cannot stack your images nor perform the histogram stretching, two crucial steps in the editing workflow for astrophotography.
In this article, we have already covered in detail how to stack astrophotography images with Photoshop. Up movie full version.
Sequator
Deep Sky And Starry Landscape Stacker Freeware Windows
Pro
- Free
- Easy to use
- Fast
- Suitable for both Starry Landscapes and Deep Sky images
- Can create Star Trails
Cons
- Windows only
- Limited set of options
- Not suitable for Planetary astrophotography
Sequator is an easy-to-use and intuitive astrophotography software for stacking both starry landscape and deep-sky images. It can also be used to create star trails.
While not as advanced as other stackers, it nonetheless allows you to calibrate your light frames with dark and flat calibration frames. It also allows you to remove light pollution, reduce noise, and perform other simple tasks on the stacked image.
Starry Landscape Stacker
Starry Landscape Stacker Commercial, $39.99 Mac OS Xhttps://tioreroka1975.wixsite.com/freemarkets/post/create-bootable-usb-with-disk-utility-mac.
Pro
- Fast
- Easy to use
Cons
- Mac Os X only
- Does not read RAW files
If you are into starry landscapes and you are a Mac user, Starry Landscape Stacker is a must-have.
Easy to use, it allows you to stack and align the sky and the foreground independently by letting you easily mask the sky.
Unfortunately, the software lacks the support for RAW formats, thus forcing you to convert your RAW images in the more heavy TIFF format.
Aside from that, it works very fast and the final image is of good quality. You can also save the sky only, which is useful to further edit the shot in Photoshop or similar editors.
Starry Sky Stacker
Deep Sky Stacker Commercial, $24.99 Mac OS X
Pro
- Fast
- Easy to use
Cons
- Mac Os X only
- Does not read RAW files
- Basic
Starry Sky Stacker is Starry Landscape Stacker brother and it has been created to stack deep sky astrophotography images. Free coins doubledown casino facebook.
As Starry Landscape Stacker, Starry Sky Stacker is very easy to use and intuitive, although very basic.
If you are a casual star shooter and a Mac user, this could be a good choice for you.
Deep Sky Stacker
Deep Sky Stacker Freeware Windows
Pro
- Free
- Easy to use
- Fast
- Full light frames calibration
- Features Comet stack modes
- Can Drizzle
- Many advanced stack options and methods available
Cons
- Windows only
- Post-processing is quite limited
- Not suitable for Starry Landscapes nor for Planetary astrophotography
Deep Sky Stacker, better known as DSS, is arguably one of the most widely used software to calibrate and stack astrophotography images.
With DSS, you can fully calibrate your images with Darks, Flats, Dark Flats, and Bias calibration frames for the best results possible. Light frames are analyzed and scored by quality so that you can decide which percentage of best images you can stack (Best 75% by default).
A very interesting feature is that with DSS, you can easily combine images taken during different imaging sessions, to produce images of higher quality.
Autostakkert!
Planetary Stacker Freeware Windows
Pro
- Free
- Easy to use
- Suitable for Planetary, Lunar and Solar images
- Stack full planetary disk and lunar surface close-ups
Cons
- Interface a bit confused
- It does not offer wavelet sharpening
- Windows only
Autostakkert!, also known as AS!, is a very popular free software among the solar system astrophotographers. With AS! it is easy to stack both images showing the full Planetary (or Lunar or Solar) disc and images showing lunar surface close-ups.
The interface is a bit confusing, particularly in the beginning, but it is easy to navigate through the different steps for the stacking.
Unfortunately, AS! does not offer wavelet sharpening, which is a widely used technique in planetary and lunar astrophotography. For this, you can load your stacked image in Registax, another freeware software for Windows only that, sadly, is now “abandoned-ware.”
Lynkeos
Planetary Stacker Freeware Mac OS X
Pro
- Free
- Has deconvolution and wavelet sharpening
- It is probably the only freeware planetary stacker for Mac OS X
Cons
- Not very intuitive
- Somewhat slower than Autostakkert!
Lynkeos is perhaps the only freeware planetary stacker software for Mac OS X, sparing you from turning to Windows for using Autostakkert!.
The interface is quite intuitive to navigate, but not when it comes to performing the different tasks.
On the other hand, it offers a deconvolution method and wavelet sharpening, a must-have for a planetary stacker. Definitely worth having a look at it if you are a Mac user.
SiriL
Deep Sky Astrophotography Editor Freeware Mac OS X, Windows, Linux
Pro
- Free
- Cross-Platform
- Active development
Cons
- A bit convoluted and not as intuitive as other stackers
SiriL is a freeware, cross-platform, astrophotography package that will let you calibrate, stack, and develop deep sky astrophotography images.
While not as easy and intuitive as Sequator or DSS, it offers a lot of options and produces good results. There is an active community, and it is under constant development.
Astro Pixel Processor
Deep Sky Astrophotography Editor Commercial $60/Yr Renter License Or $150 Owner License Mac OS X, Windows, Linux
Pro
- Full-grown astrophotography package
- Fairly easy to use
- Mosaics are created with ease and are of great quality
- Active and constant development
- Cross-Platform
- 30-days Trial period
- Affordable yearly subscription
Cons
- Only for deep sky astrophotography
- No Comet stacking mode
With Astro Pixel Processor (APP), you step in the realm of full-grown astrophotography packages, with many advanced options and methods to calibrate, stack, and post-process your deep-sky images.
Compared to PixInsight (PI), the software benchmark for the category, APP is cheaper and way easier to use, which makes it one of the best PI alternatives.
Linux Create Panorama
If you decide to buy it, you can choose between the renter’s license for $60/yr, to always get the latest version of APP, or the owner’s license for $150, but you will have to purchase the license again for major update releases.
PixInsight
Astrophotography Editor Commercial – €230+VAT Mac OS X, Windows, Linux
Pro
- It has all you need for astrophotography
- 45 days trial period
- A lot of tutorials and information available
Cons
- Expensive and without subscription plan
- Extremely steep learning curve
- Long and convoluted process
- Needs a powerful computer
When it comes to astrophotography, PixInsight is the software of reference against which all others are measured. It offers everything you may possibly need to produce pro graded images, and it is objectively the best software in the field.
But user experience can be frustrating, as the learning curve is very steep, the editing is long and convoluted, and your computer must be quite recent and powerful to make it run smoothly.
The €230 + VAT price tag is also quite steep: sure it is worth every penny, but this makes PI be even more the software of choice for professional and keen amateur astrophotographers.
A Comprehensive Demo About Image Stacking
In this video, I show you how easy it is to wet our feet with image stacking.
This is particularly true if you use Starry Landscape Stacker, Sequator, Deep Sky Stacker and Autostakkert!, as I showed in the video below.
Conclusion
Image stacking is one of the crucial steps in the astrophotography editing workflow.
You’ll need the appropriate stacker for each type of astrophotography: starry landscapes, star trails, or deep-sky and planetary images.
In this article, we have covered the most popular astrophotography stackers available on the market, both freeware and commercial.
And while Windows users have the more extensive choice, some notable stackers are available for Mac and even Linux users.
The view from the top of Glastonbury Tor is breathtaking. You can see for miles and miles across multiple counties in a stunning 360-degree panorama.
When I visited I (naturally) couldn’t resist trying to capture the impressive view. Wanting something a little more immersive than a standard (and constrained) snap I used the ‘Photo Sphere’ feature on my Nexus 5X’s camera app to take a multi-shot panoramic photo.
On Android I can view, pan and orbit around this image in 3D, spherical way, as I can in the browser when I view it on Google Photos.
But what if I want to view 360 panoramic photos on Ubuntu in the native image viewer? Does it work? Can I?
Linux Pandora
Well, the short answer is yes. Eye of GNOME supports panoramic and photo sphere photos out of the box. The downside is how it displays such images by default: as a long, linear, horizontal strip:
Sure, I can zoom in and then pan, but it’s still a flat experience for an image that, on other devices, can be viewed in a more intimate way.
Panorama Photo Viewer for Eye of GNOME
Thankfully a developer is working on a plugin solution for Eye of GNOME, the default image viewer on Ubuntu — and about time, too!
The ‘eog panorama’ plugin by Aerilius brings a 360 panorama viewer feature to the image viewer of Ubuntu. The plugin is ideal for anyone that wants to view panoramic photos on a PC or laptop.
These days most of us have a smart phone in our pocket, and this ubiquity has undoubtedly helped the humble panorama become popular as a photo format. In turn, web services and social networks have, accordingly, help standardise XMP-tags so that software knows when and how to display a panorama image correctly.
So it’s only right that the Linux desktop keep pace too.
Eye of GNOME image viewer is able to show panoramic images, just not in an imaginative way. As developer Aerilius puts it: “a spherical projection would be smarter and more comfortable than displaying a panorama photo as a long horizontal strip”.
Viewing my Glastonbury Tor image on Android (or on the web in Google Photos) is super immersive; I feel like I’m surrounded by the that left me speechless every time I look at it.
On Ubuntu, in Eye of GNOME, that experience is… It’s static.
Linux Pandora App
But with Aerilius’ plugin for EOG panoramic photos are automatically detected and displayed using a scannable spherical stage.
Download EOG Panorama Plugin
Now, I have to caution here that this plugin does not work for me. I generally don’t like to write about any app or plugin when this happens, but I will make an exception in this instance.
Firstly because, despite the plugin not working for me, this plugin is working for other people. And secondly, because I know of nothing else like this on the Linux desktop. What Works?
Any correctly tagged Panorama photo should work with the following plugin installed and activated.
To check XMP metadata of an image in EOG:
- Image > Image Properties > Details
- In the “XMP other” section you should see have
GPano:UsePanoramaViewer = Trueand other GPano metadata.
Photos taken by mobile phones or patched together using third-party software add this metadata automatically.
How To Install
You’ll need to install the following dependency before installing the plugin:
Next, download the plugin:
Once fully downloaded extract the zip full and move the ‘eog_panorama‘ folder inside the extracted directory to ~/.local/share/eog/plugins/. If this folder stack doesn’t exist you will need to create it using the ‘New Folder’ option in Nautilus.
Once the plugin directory is in place you can go ahead and enable it.
- Open Eye of GNOME
- Go to
Edit > Preferences > Plugins - Check the box beside the ‘
EOG Panorama‘ plugin
That’s it!
The next time that you open a supported image in the viewer the new plugin should kick in and handle the rendering. Due to limitations of using a WebView be aware that crazy his-res panorama images may cause high CPU and memory use during loading.
Linux Panorama Stitching Software
Does It Work?
If your lengthy panorama photos don’t look any different with the plugin installed you’re probably hitting the same issue as me: the script failing to kick in to gear in the background. I’ve tried to find the reason it fails on my box (but works on others) and have so far come up with nothing.
If any of you are able to find out the cause, please do report your findings on the plugin’s Github page.