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View Full Version here: : Work in Progress 10 Gigapixel Milky Way Mosaic


plantnerd
08-10-2016, 02:16 PM
For over a year I have been working on a mosaic of the whole milky way.

I am using basic equipment my 35mm FOV is 300mm or 8.2 degrees wide.
The lens is Olympus Zuiko Digital 150mm F2.0 one of the finest telephotos ever made almost free of chromatic aberration when wide open and perfect at F2.2 it holds a world record for sharpness. The camera is a Mirrorless 4/3 sensor 16 megapixels I use ISO 1600 as this is the maximum I am comfortable with for noise and I am using Ioptron Skytracker to manually find areas of Sky that I have not covered so no automation exposure times vary from 30 seconds to 1 minute but frames overlap so average 1 minute in any area @ F2.0 iso 1600.

The mosaic so far is composed of 2662 X 16 Megapixel RAW images.

Currently covers the area from Orion Through Carina and The Milky Way Core and Lagoon Nebula to The Dumbell Nebula coverage up includes the Large Magellanic Cloud and Down to Rho Opiuchi.

Field of View is 257 Degrees X 80 Degrees.
180,000 Pixels X 56,000 Pixels = 10,111 Megapixels.
Probably have data for about 55% of the area of 5.5 gigapixels so far.

The second and third images are Crops of the Orion and Running Man Nebulae and The Lagoon Triffid Nebulae Just to show the insane resolution we are dealing with in this mosaic.

Still quite a few gaps to fill but getting there.
Any comments or tips appreciated.

A 300 megapixel 16% resize 30K X 10K pixel Version of the Original 10Gigapixel image is located here for your exploration
Warning 140mb Download!
https://dl.dropboxusercontent.com/u/29904149/MilkyWay/%5BGroup%200%5D-P1160413_P2143435-2506%20imagesHVLGCvsCol.jpg

Atmos
08-10-2016, 02:28 PM
Very nice Luis! I am currently working on a 1 gigapixel around Sagittarius as a test before doing the same thing next year and working on a 25 gigapixel.

What are you using to process and stitch them together?

plantnerd
08-10-2016, 02:38 PM
I could probably get near 25 gigapixels if I did the whole sky but I think I will stop once I have the band with the Milky Way Magellanic Clouds Andromeda and Triangulum.

I am stitching with Autopano Giga
Stitching has become a supercomputing problem with such a large dataset. Takes about 4 hours to render a new version with my current workstation that has Dual 6 Core CPUs at 2.8ghz and 32GB RAM.

I am building a better Workstation with 32CPU Cores and 64GB RAM.
Also a PCI Express SSD doing 1GB per second of HDD speed and 7990 GPU which does 8 teraflops and 2 teraflops double presision for scientific calculations.

I will probably have to move to GPU stitching with something like PTGUI or use Professional Linux Astronomy software like SWARP.

plantnerd
08-10-2016, 02:49 PM
What equipment are you using Colin?

pluto
08-10-2016, 02:59 PM
Very nice!
I'm assuming the camera is not modified?
Anywhere we can see the full res WIP?

Atmos
08-10-2016, 03:01 PM
About half an hour ago I finished doing my first pass of processing on all 100 images (10x10 panel mosaic at the moment).

This is a quick stitch of a 3x3 and a crop of the resolution.

I am using a Nikon D700 and my 130mm F/5 refractor so it is effectively a 670mm F/5.1 lens (plate solved). For this one I have only been able to use 60s exposures at ISO1600 (took all of them last Saturday night, due to Sagittarius setting I couldn't go longer). I REALLY need 120s especially for some of the lower signal areas as there is too much noise. Unless I can swamp the camera read noise there is some low electrical noise that cannot be processed out.

Next year I'd like to attempt a 15x15 using a Nikon D810a and collect 80-100 hours of data

plantnerd
08-10-2016, 03:10 PM
Yes camera is unmodded but still fairly sensitive to Halpha.
I am looking to get a modified camera.

I dont have a full resolution as JPEG format only supports 64000pixels wide
I have a 16% resolution 30000 pixel version that is 125MB that I can dropbox to you if you are interested Hugh?

plantnerd
08-10-2016, 03:24 PM
Wow colin 670mm is really long for such A big mosaic and I thought I was crazy shooting at 300mm. Your F5 seems to be adding some noise to your 60sec exposures even though your camera should be a fair bit better than mine for noise.

That is the beauty of F2.0 my lens is effectively like a small SCT with hyperstar so 30 seconds gets pretty deep and not too much noise but I might upgrade my camera to a modded one or 20mp with lower noise and if I nail polar alignment I should be able to do 60secs.

I also have a NEQ6 so I want to try to program that to do the mosaics automatically.

pluto
08-10-2016, 03:25 PM
That'd be great Luis, I never get tired of just browsing the Milky Way :)

Atmos
08-10-2016, 03:39 PM
It get some pretty nice detail if nothing else :P Pixels are still really big at 8.445 micon so that is one reason I'd like to go for a Nikon D810a with its 36.8mp sensor :P

60s is REALLY not enough for this camera, it cleans up considerably better at the 120s mark at ISO1600. I have found that if I don't get above the read noise it is very bad. These were shot at 32º above horizon so also not very well placed.

Atmos
08-10-2016, 04:50 PM
I am still deciding whether I should be putting in the effort to match up every frame yet. Probably should so that I can have a nice wall mount at the end :P Anyway, this is a 3x10 that I've just "finished".

How do you go about matching each frame so that they stitch together nicely without the harsh boarder?

plantnerd
08-10-2016, 05:16 PM
Autopano Giga does all the blending itself but it costs $ try Microsoft ICE Image Composite Editor it is free and does a pretty good job until you get to 1000 images or so. The right click on your images and Stitch using ICE is a nice touch as well if you use PC.

ICE might be the best ever Microsoft product and they give it away free
http://research.microsoft.com/en-us/um/redmond/projects/ice/

strongmanmike
08-10-2016, 05:51 PM
Talk about dreaming big and aiming high Luis, wow :eyepop:, your project is about as ambitious as they come and I wish you all the patience that will be necessary, so far it is really looking quite impressive, indeed! :thumbsup:

I have posted this before but it is always good to compare when threads like yours come up, myself and a mate did something similar in the good'ol photographic days, over a single clear night. How far we have come and how much we can do now is really amazing. Unfortunately the only surviving photo of our mozaic (http://www.pbase.com/strongmanmike2002/image/110764947/original) is slightly out of focus, the actual mozaic was significantly sharper, see details under the image :)

As young men we even contemplated tackling what you are tackling...buuuut gave up after more careful consideration of what it would have entailed :lol:

Mike

Octane
09-10-2016, 09:50 AM
GradientMergeMosaic in PixInsight.

It's a long and drawn out process.

You essentially build a proxy/scaffold mosaic which is basically a mask of where each panel is meant to go in the overall grand mosaic. Then, you perform the mosaic merge itself which produces a seamless mosaic by placing each panel into the scaffold and blending it with the panels beside it.

You still end up with artifacts along the edges, especially if there are bright stars on the edges; you then have to cut each of them out from the offending panel and run the merge again.

It takes a long time, but, the results are worth it.

One I started six years ago but have not finished yet: http://www.iceinspace.com.au/forum/showthread.php?t=139766

H

plantnerd
09-10-2016, 10:16 AM
Thanks Mike and others for the encouraging words you guys certainly do incredible work and a little science as well. I am proud to be part of this amazing community.

Anyone that wants to explore a mere 30,000 X 10,000 pixel (300 Megapixel) Version of the 10 Gigapixel original

Warning 140MB Download!
https://dl.dropboxusercontent.com/u/29904149/MilkyWay/%5BGroup%200%5D-P1160413_P2143435-2506%20imagesHVLGCvsCol.jpg

Regulus
09-10-2016, 03:31 PM
Nice work Luis, I look forward to the end result.
Big file sizes just say to me: this is gonna be worth a look :-)

Trev

gregbradley
09-10-2016, 05:59 PM
This should really be its own thread not in Luis's thread.

Nice work Luis. I admire your persistence and hard work at getting the final result. Mosaics of the Milky Way are something we are uniquely able to do here in Oz so it makes sense as a project.


greg.

pluto
10-10-2016, 10:30 AM
That 300MP version is great Luis!