Galaxy challenge - 135MP image - How many can you see?

[Elp]

Hopefully I can submit to the SGL galaxy challenge June 2023, it was ready on Wed, uploaded Thu...

This challenge always attracts many excellent submissions and this year follows on with the trend. Some truly excellent pieces of work there.

I decided to divert from the general consensus, something I’ve wanted to do for a number of seasons but it’s always difficult with short nights and non astronomical darkness, but I never like to leave a clear night un-imaged so even whilst imaging right next to the moon I wanted to do this… try and image the most amount of galaxies in one wide FOV image.

This is my first mosaic.

Originally when planning this mosaic I went nuts and wanted to include the whole Coma Berenices region downward, but it was a 75 panel mosaic, impossible for one season (and truly will take years) and I can’t image the whole thing as maybe half is below the horizon, checking the framing would also be a nightmare so I decided to simplify and start with that often imaged target Markarian’s Chain, a wonderful target in itself but also an ideal datum point to start from and work outward.

The original plan was to image luminence with one scope, and r, g, b with another, I nearly managed a 20 minute per panel pass of the colour but stopped short on the blue due to time (lower panels set too quickly after dark and they really need longer imaging time overall per filter). The weather’s been decent of late during the day but come night the clouds like to roll in, and if not that the wind decides to turn up and the usual suspect the moon is where I want to image like it reads my mind. The last session I got fed up and imaged next to the moon, data wasn’t bad, wasn’t the best either but I decided not to use it. So every time I’ve imaged wide with my excellent Z61, my second setup has also been imaging but I decided not to use that data, mainly because it was a smaller field of view and trying to match everything will have been a massive undertaking. Even this simple end result rough as it is with many defects (and I may have destroyed a few trillions of innocent distant civilisations in the process when cleaning up the image) took probably longer than the image acquisition as it was stacked and pre processed in Siril and aligned and colour matched and cleaned up manually in PS. No auto stitching software worked because when cross referencing the auto stitched images with object positions on my manually aligned image and referencing Stellarium, the auto software scaled and rotated panels in odd ways causing distortion so I don't believe they stitch accurately.

So in the end I only managed a 3 x 3, 9 panel mosaic approximately 8 x 6 degrees FOV at 1 hour per panel (dropped to 54 minutes with final stack rejection).

The image won’t win any awards but I’m submitting it, it’s my first attempt at a mosaic, and my first attempt doing a wider than normal field of view, hopefully some viewing it will like it, even better if it inspires others to attempt similar. 

Think I may add to it per season……

Best viewed at 100 percent, I’d recommend you try to count as many smudges you can see on the plain image first. Once you’ve done that come back to the below.

For reference this is the astrometry plate solve on a lower res version, around 317 objects annotated:

And by my rough observation this many are visible (160 odd), think this is quite the result for such a short imaging time. It’s amazing what’s possible nowadays.

Edited July 5, 2023 by Elp

[WolfieGlos]

Elp, that is an incredible effort! 👏 For only 54mins per panel as well.

Definitely enter it, I've just put one in which I was going to enter but due to forum downtime hopefully it's accepted.

I've been considering doing a mosaic of this region next year so this is the inspiration I need! I've done 2 mosaics so far...1 I've posted, other I haven't....both have been 2x1's and I stitched those with ASTAP. It worked quite well for me 👍

[Elp]

I'd say go for it, it's great picking up the non obvious things which linger in the background. My question is, why is this region so populated with galaxies?

[AstroMuni]

On 03/07/2023 at 16:29, Elp said:

My question is, why is this region so populated with galaxies?

Wonderful mosaic.

My understanding is that this is part of the Virgo supercluster and the original thinking that galaxies would be evenly distributed across the universe is not correct - they tend to clump.

 

Edited July 5, 2023 by AstroMuni

[AstroGS]

@Elp you should be very proud of yourself. This is a brilliant image and amongst the best for the SGL Galaxy challenge for this year, in my opinion.

Well done buddy.

[Elp]

2 hours ago, AstroGS said:

@Elp you should be very proud of yourself. This is a brilliant image and amongst the best for the SGL Galaxy challenge for this year, in my opinion.

Well done buddy.

Thanks, always wanted to do something like this, it's likely going to be an annual project starting earlier in the year so I've got more time (weather permitting as it's usually very unsettled). Eventually maybe add in RGB.