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Tuesday, August 8, 2023

Grand Mosaic of the Milky Way is now large than ever


Last spring, I published a large mosaic photo of the Milky Way, and it went viral!
You can read a blog post about it here: Gigapixel Mosaic of the Milky Way.

Now, I have an even larger version of the mosaic, spanning an impressive 145 degrees of sky—from Orion to Cygnus. The previous version covered 120 degrees.
This new panorama was published today for the first time in the world by the Finnish Tähdet ja Avaruus magazine.



The Grand Mosaic of the Milky Way Galaxy II

This is the only photograph in the world that captures the Northern Milky Way with such incredible depth and detail—and now, it’s larger than ever!

Click for a large image, 7000 x 1150 pixels

Over a decade of work, 1500 hours of exposure, and 301 individual frames—all captured in a single image. Note: An image of the Full Moon is included in the lower left corner for scale.



NEW! ZOOMABLE IMAGE
23.000 x 3500 pixels


You can now pan and zoom around the large image!

For better accessibility and to save bandwidth, the photo size has been reduced to 40,000 × 6,000 pixels from the original 120,000 × 18,000 pixels.

Note: All material on this blog is copyrighted. Any use without the author's permission is strictly prohibited.







IMAGE SPECS
  • Panorama spans 145 x 22 degrees of sky (Full Moon covers 0,5 degrees of sky)
  • Resolution 120.000 x 18.000 pixels
  • Photos has 2.2 gigapixels in it, the spatial resolution is equal to 8.8 gigapixel image from color camera since all the channels are in native resolution.
  • There are least nine confirmed supernova remnants in this panorama
  • About 25 million stars are visible in the photo
  • Distance to the nebulae in the image between 350 to 20.000 light years
  • Exposure time over 1500 hours between 2009 - 2021
  • 301 individual images are stitched together seamlessly 
  • It took about 12 years to finalize this photo
  • Narrowband image from light of ionized elements,    hydrogen = green, sulfur = red and oxygen = blue
  • Processing time for the whole panorama, way too large part of my life


ORIENTATION

Click for a large image

The high-resolution panoramic photo spans 145 degrees of the Northern milky way



CLOSEUP SERIES
Click for the large images, it's worth it!

A zoom in series from upper left of the large panorama image above to gives an idea about the overall resolution of the large mosaic image.


All the dots are stars, not the noise!


Closeup of the supernova remnant IC 443



DETAILS

Click for a large image, 5000 x 1500 pixels

There are several very dim and practically unimaged supernova remnants in this panorama.
NOTE, all material in this blog is under copyright, any kind of usage without authors permission is forbidden.


NEW! ZOOMABLE IMAGE

11500 x 3400 pixels




WHY?



The reason I continue this slow and meticulous work is simple: endless curiosity. I love revealing the true wonder of our universe, showing just how extraordinary our world really is. Every time I look through my camera, I am in awe of what I see, and capturing that beauty is my purpose as an artist. For the past 25 years, I have been driven by the need to fulfill my passion.

This image showcases a vast section of the Northern Milky Way in high resolution. Beyond its sheer size, it reaches incredible depths, revealing exceptionally faint and previously uncharted nebulae across the galactic plane. One of the main motivations behind this massive panorama project was the simple fact that an image like this did not exist anywhere in the world. I needed a photo like this—a map to guide my future explorations.

Unveiling the hidden beauty of our universe is my passion. I stand in rapt adoration before everything I capture. When art meets science, the results can be truly mind-blowing.



HOW?



Step 1, 

PLANNING

Astrophotography is an incredibly time-intensive process. To create a color image, I must capture each target at least three times, using different filters to obtain the necessary color channels. Additionally, exposure times can be extremely long—some of the faintest objects require hundreds of hours of exposure. On average, each image in this project took around 25 hours to complete. Every step must be carefully pre-planned to achieve the best results.

I began planning this project over a decade ago, jotting down my first ideas in a small black Moleskine notebook. Even then, I knew it would take ten years to complete—but that never discouraged me. I love long-term projects; they provide both purpose and a goal, driving my work as an artist.


My little black notebook and first plans for the project at 2008

A notebook page opening from Autumn 2008



I had to develop many new working methods to successfully manage this massive project. These methods had to be perfected before starting, because once the project was underway, any major changes would have required canceling it entirely.

Every detail had to be precisely planned—from the composition and its alignment with Milky Way structures to numerous technical aspects, such as handling data from different optical systems with varying spatial resolutions.

I won’t go too deep into the technical details, as the complex techniques involved are simply tools—a means to create my art.



A notebook pages from 2009



I like to compare my long imaging projects to a relationship. But in this case, it wasn’t just between two entities—it was like being in a relationship with an entire family, a large and complex clan. Just like in a family, there might be a difficult uncle or some other challenging personalities, but you have to learn to work with them. I felt the same way while stitching together the pieces of this mosaic. Some frames simply didn’t fit the way I wanted, forcing me to reshoot them, which often took months or even years. But in the end, everything came together seamlessly, without any visible gaps.

I am a perfectionist when it comes to my photography. While this trait is essential for achieving great results, it can also be a challenge. This photo could have been finished five years earlier if I had been willing to leave out some of the extremely faint targets or settle for less detail—but I simply couldn’t.

Yet, when the image was finally complete, I didn’t think about all those sleepless, freezing nights. Instead, I remembered the pure joy I felt when the most challenging parts finally came together.



Step 2, 

COLLECTING THE MATERIAL 

2009 - 2021


NOTE

Each photo in the posters is a slow and complex battle of its own

Click for a large image



 
Some of my individual photos shot between 2009 and 2021 are collected here. Most of them are now part of the Large Mosaic Image of the Milky Way galaxy.
NOTE, all material in this blog is under copyright, any kind of usage without authors permission is forbidden.


Step 3, 

2019 -2021, SOLVING THE BIG PUZZLE



Finally, in 2019, after so many years of work, I had gathered enough material to begin assembling the final mosaic image. The process took nearly two years due to the complex structure of the mosaic and the sheer volume of image data.

At the same time, I also had to capture additional missing material to complete the mosaic, making the process even more time-consuming. But every piece was essential to ensure the final image was as detailed and seamless as possible

I used the Cartes du Ciel, a star map software, for planning and a preliminary fit the individual frames.








EVOLUTION OF THE LARGE MOSAIC

BETWEEN 2009-2021

Click for a large image

This image collection show the evolution of my Large Mosaic of the Milky Way Galaxy.


Step 4,
 

ALL THE PIECES OF A 

 COSMIC PUZZLE CONNECTED

Click for a large image

The final photo is over 120 000 pixels wide and it has 301 individual mosaic panel. Most of the objects are originally shot as a self-standing artworks, due to that, they are in various positions and angles to each other. This is the reason, why the final mosaic structure looks so complicated, as can be seen in this image.

AND FINALLY

At October 2021, after 12 years, 1500 hours of exposures and countless hours of work

The Grand Mosaic of the Milky Way Galaxy II

Click for a full size image, 7000 x 4300 pixels
NOTE, all material in this blog is under copyright, any kind of usage without authors permission is forbidden.


Reaching the final piece of a puzzle is always a thrilling moment. Many of us know the frustration of realizing that a crucial piece is missing—and that happened to me too.

I was certain I had captured that particular section three years ago, yet no matter how hard I searched, I couldn’t find it on any of my hard drives. As a result, I had to endure several painfully long weeks waiting for the right conditions to reshoot the missing piece. Only then could I finally complete this massive cosmic puzzle.


The Mosaic Work, technical info

Optical Configurations

Over the years, I have used several optical setups to capture this mosaic.

  • Up until 2014, I worked with a Meade LX200 GPS 12" telescope, a QHY9 astro camera, Canon EF 200mm f/1.8 optics, and a Baader narrowband filter set.
  • Since 2014, I have used a 10Micron 1000 equatorial mount, an Apogee Alta U16 astro camera, a Tokina AT-X 200mm f/2.8 lens, and an Astrodon 50mm square narrowband filter set.

I have also captured many high-resolution details using longer focal lengths:

  • Before 2014: Meade 12" telescope with a reducer
  • After 2014: Celestron EDGE 11" with a reducer
  • Guide cameras: Lodestar and later Lodestar II

I chose my current setup as the base tool for this project because it offers a high resolution combined with an exceptionally large field of view. Additionally, it collects photons very efficiently due to being undersampled, allowing extremely faint background nebulosity to become visible in a relatively short exposure time—often, a 30-minute frame is sufficient.

Mosaic Processing

I assemble all my mosaic images in Photoshop. Aligning the individual panels using stars as reference points is fairly straightforward. Over the years, my processing workflow has become so consistent that only minor adjustments—such as small tweaks to levels, curves, and color balance—are needed between frames.

To enhance details, I have incorporated many high-resolution subframes into the mosaic (see the mosaic map at the top of the page). To seamlessly integrate longer focal length images with shorter focal length data, I developed a custom method:

  1. Upscale the short focal length frames by ~25% to provide more room for high-resolution data.
  2. Match the high-resolution image to the mosaic, using stars as reference points.
  3. Remove all tiny stars from the high-resolution image to prevent optical distortions.
  4. Separate the stars from the low-resolution image and blend the starless high-resolution data with the starless low-resolution frame.
  5. Reintroduce the removed low-resolution stars on top of everything—ensuring zero data loss and maintaining a uniform star field across the entire mosaic.

This method eliminates optical distortions, which are especially noticeable in dense star fields. Since all stars in the final image originate from the same optical setup, I avoid inconsistencies. I use the same star removal technique as in my Tone Mapping Workflow to achieve this seamless integration.




5 comments:

Anonymous said...

Aivan käsittämättömän suuren työn olet tehnyt!! Suu loksahti auki noita kuvia katsellessa. KIITOS kun jaoit kuvat ja tämän kokemuksen!! Ei voi muuta kuin arvostaa ja ihmetellä...

Mika said...

Vautsi!

William Silversmith said...

This is really beautiful and a ton of work! If you are looking for a way to present the whole image to the world (or even locally to yourself) at full resolution, take a look at https://github.com/google/neuroglancer which we use for displaying huge electron microscopy datasets. There might be astronomy packages that are more specialized, but it's what came to mind the soon as I saw this since I work with it everyday. I am the author of the https://github.com/seung-lab/igneous package that is used for converting raw images into these kinds of volumes and I'd be happy to give advice if this is useful.

There are other methods you can use such as https://imagej.net/plugins/bdv/ as well that I am less familiar with.

I'm sure you already have something analogous that you're using, but just wanted to point this out in case it's helpful.

Thanks for sharing your journey and art with us! It's inspiring for this extremely amateur astronomer to see this kind of work.

Anonymous said...

Pakko sanoa että sulla on ollut aivan mieletön projekti, hienoa nähdä noin suurta intohimoa kuvaukseen.

NorthSanta said...

Wow What a work!!! Good man and deserves all respect!!