All the material on this website is copyrighted to J-P Metsavainio, if not otherwise stated. Any content on this website may not be reproduced without the author’s permission.

Have a visit in my portfolio

Monday, February 28, 2022

Milky Way, 12 years, 1250 hours of exposures and 125 x 22 degrees of sky THIS IS A PERMANENT POST, NEW POSTS ARE AFTER THIS POST

You can buy prints by using the contact form at right

It took nearly twelve years to collect enough data for this high resolution gigapixel class mosaic image of the Milky Way.  Total exposure time used is around 1250 hours between 2009 and 2021.

" I can hear music in this composition, from the high sounds of sparcs and bubbles at left  all the way to a deep and massive sounds at right."

The final photo is about 100 000 pixels wide, it has 234 individual mosaic panels stitched together and 1,7 gigapixels. (Click for a large image) All the frames used are marked in this image. Since many of sub-images and mosaics are independent artworks it leads to a very complex mosaic structure. 

From Taurus to Cygnus
Click for a large image, it's really worth it! (7000 x 1300 pixels)

Image in mapped colors from the light emitted by an ionized elements, hydrogen = green, sulfur = red and oxygen = blue. NOTE, the apparent size of the Moon in a lower left corner. NOTE 2, there are two 1:1 scale enlargements from the full size original at both ends of the image

NEW, A HD-video from Germany shows my photo in full glory
(Video in Germany but images are the international language)

Close ups form the parts of the Grande Mosaic
Taurus side of the mosaic,

A closeup from large panorama to show the overall resolution
Click for a large image

The California Nebula, NGC 1499, can be seen at bottom left of the large mosaic image.
There are about 20 million individual stars visible in the whole mosaic image.

Orientation and details
Click for a large image

Imaging info

Image spans 125 x 22 degrees of  the Milky About 20 million individual stars are visible in my photo!

It took almost twelve years to finalize this mosaic image. The reason for a long time period is naturally the size of the mosaic and the fact, that image is very deep. Another reason is that I have soht most of the mosaic frames as an individual compositions and publish them as independent artworks. That leads to a kind of complex image set witch is partly overlapping with a lots of unimaged areas between and around frames. I have shot the missing data now and then during the years and last year I was able to publish many sub mosaic images as I got them ready first.

My processing workflow is very constant so very little tweaking was needed between the mosaic frames. Total exposure time is over 1250 hours. Some of the frames has more exposure time, than others. There are some extremely dim objects clearly visible in this composition, like a extremely dim supernova remnant W63, the Cygnus Shell. It lays about six degrees up from North America nebula and it can be seen as a pale blue ring. I spent about 100 hours for this SNR alone. An other large and faint supernova remnant in Cygnus can be seen at near right edge of the image. G65.5+5.7 is as large as more famous Veil nebula. There are over 60 exposure hours for this SNR alone.  (Veil SNR is just outside of the mosaic area for compositional reasons but can be seen in "Detail" image above.) 

The Mosaic Work, technical info

I have used several optical configurations for this mosaic image during the years. Up to 2014 I was using an old Meade LX200 GPS 12" scope, QHY9 astrocam, Canon EF 200mm f1.8 camera optics and baader narrowband filter set. After 2014 I have had 10-micron 1000 equatorial mount, Apogee Alta U16 astro camera, Tokina AT-x 200mm f2.8 camera lens and the Astrodon 50mm square narrowband filter set. I have shot many details with a longer focal length, before 2014 by using Meade 12" scope with reducer and after 2014 Celestron EDGE 11" and reducer. Quider camera has been Lodestar and Lodestar II.

I took my current toolset as a base tool since it has a relatively high resolution combined to a very large field of view. Also it collects photons very quickly since it's undersampled and I can have very dim background nebulosity visible in very short time (many times 30 min frame is enough)

I do all my mosaic work under the PhotoShop, Matching the separate panels by using stars as an indicator is kind of straight forward work. My processing has become so constant, that very little tweaking is needed between separate frames, just some minor levels, curves and color balance. 

I have used lots of longer focal length sub-frames in my mosaic to boost details. (See the mosaic map at top of the page) To match them with shorter focal length shots I developed a new method.

Firstly I upscale the short focal length frames about 25% to have more room for high resolution images.Then I match the high res photo to a mosaic by using the stars as an indicator. After that I remove all the tiny stars from the high res image. Next I separate stars from low res photo and merge the starless high res data to a starless low res frame. And finally I place the removed low res stars back at top of everything with zero data lost. Usually there are some optical distortions and it's seen especially in a star field. Now all my stars are coming from a same optical setup and I don't have any problems with distortions. (I'm using the same star removal technique as in my Tone Mapping Workflow)

Closeups from large panorama to show the overall resolution
Click for a large image

Image in mapped colors from the light emitted by an ionized elements, hydrogen = green, sulfur = red and oxygen = blue. 

A 1:3 resolution close up from the photo above
Click for a large image,

A closeup from the main image shows the Sharpless 124 at up and the Cocoon nebula with a dark gas stream at bottom.

From Bubble to Cave Nebula
Image info,

The tulip nebula area
The Tulip Nebula, Sh2-101, can be seen at center right, there is also a black hole Cygnus X-1
The blog post with technical details can be seen here,

The supernova remnant G65.3+5.7

My Observatory,

Not an igloo, this is reality of astro photographing in Finland

Sunday, February 27, 2022

Cederblad 214, the Cosmic Question Mark

I have published this photo back in February 2020 but I have done some reprocessing and repost this image now since this photo of Cosmic Question Mark has symbolic value to me. A cosmic curiosity is the very reason I'm doing this difficult, and sometimes frustrating, form of nature photographing art.

Cederblad 214, the Cosmic Question Mark
Click for a large image

Image info, technical data and more images of this object,

Friday, February 25, 2022

4K HYPER Zoom to the Milky Way and a Bubble Nebula

I have made couple of 4K videos out of my massive 145 degree Milky Way panorama. In the video you can see the actual resolution of this massive image. This time I'm zooming into the Bubble Nebula in cassiopeia at distance of about 12.000 light years.

Super Zoom to The Bubble nebula (44 seconds)

Best seen as a full screen and better yet, with a 4K display, direct link to the YouTube:

Info about the large panorama of the Milky Way
(Click the image to enter)

Over a decade, 1500 exposure hours and 301 individual frames visible in one image
NOTE, image of the Full Moon as a scale in lover left corner.

Info about the Bubble Nebula
(Click the image to enter)

Thursday, February 24, 2022

4K zoom in the Milky Way

 I made a 4K video out of my massive 145 degree Milky Way panorama. In the video you can see the actual resolution of this massive image when it zoom in to IC 1396 in constellation Cepheus

Super Zoom to IC 1396

Best seen as full screen and 4K display, direct link to the YouTube:

Info about the large panorama of Milky Way:

Wednesday, February 23, 2022

It's beautiful because it's true


My deepest motivation to keep doing this slow artform

Super Zoom to my photo, the Grand Mosaic of the Milky Way Revision 2

4K Super Zoom to my photo
Grand Mosaic of the Milky Way Revision 2

Super Zoom to the Milky Way, note, best to see in full screen

It took over 12 years to finalize this massive photo of Milky Way
Blog post with a zoomable image, please, have a look here:

  • 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

Monday, February 14, 2022

Supernova remnant HB3 and the cosmic heart

 I have shot this target originally at January 14 2020 and it was the second light to my modified Tokina lens. Now I have reprocessed the data and I do like this result much better.

 new imaging system based on Tokina AT-x 300mm f2.8 camera lens.

The Heart Nebula, IC 1805
Please, click for a large image

Going very deep just in two hours! Image is in visual color palette from emission of an ionized hydrogen and oxygen. R=hydrogen, G=Oxygen and B=oxygen. I have made a starless version out of this image, it can be seen here,

IC 1805 in visual palette
Please, click for a large image

Supernova remnant

In this photo there is a large supernova remnant, marked as a white circle. I haven't seen any photos of it before. I must take more O-III exposures to see, if I'm able to pick up any signal from this supernova remnant. 

Radio image of the area shows mostly signal from OB6

SNR 132.7+1.3 at upper right. Source and more information,

Technical details

Processing workflow
Image acquisition, MaxiDL v5.07.
Stacked and calibrated in CCDStack2.
Deconvolution with a CCDStack2 Positive Constraint, 33 iterations, added at 50% weight
Color combine in PS CS3
Levels and curves in PS CS3.

Imaging optics
Tokina AT-x 300mm f2.8 camera lens

10-micron 1000

Cameras and filters
Imaging camera Apogee Alta U16 and Apogee seven slot filter wheel
Guider camera, Lodestar x 2 and an old spotting scope of Meade LX200

Astrodon filters,
5nm H-alpha 3nm S-II and 3nm O-III

Total exposure time
H-alpha, 12 x 600 s, binned 1x1 = 2 h
O-III, 3x 600 s, binned 1x1 = 30 min..
S-II, 2x1200 s, binned 2x2 = 40 min.

INFO About undersampling etc

The CCD I'm using has kind of large pixels, 9 microns, so I'm undersampled, the image scale is almost 5 arc seconds / pixel. Undersampling is not a bad thing when my targets are large and dim nebula complexes. This system collects photons very fast!

I selected the Heart Nebula as a target since I have plenty of reference material for it. Another reason is interesting and rarely imaged area after the bright tip of the heart. There are some remnants of a supernova explosion. I was really thrilled, when I saw the final stack of 12 600s H-alpha light frames. (Equal to 2h of exposures) I never have seen so much background nebulae and details from this popular target.
Beside 2h of H-alpha (Light from an ionized hydrogen) I shot 30 min of O-IIII (Light from an ionized Oxygen) To be able to make an image in visual palette.