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M52, Bubble Nebula, Lobster Claw Nebula

Started by MarkS, Sep 30, 2018, 19:52:40

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MarkS

Here is my first "proper" image from Astrofarm - the comet images were just a minor distraction  ;)

It covers the region containing M52, the Bubble Nebula and the Lobster Claw.

240x30sec exposures at ISO 10000 using modified Sony A7S on Tak Epsilon 180ED.  Processing was dead simple: stacked using Bayer Drizzle,  Background subtraction using ABE (linear function), ArcsinhStretched with factor 40 and then given some saturation in Photoshop.



It needs to be seen full-size to really appreciate it:
http://www.markshelley.co.uk/Astronomy/2018/m52_bubble_claw20180908.jpg

This is pane number 1 of a mosaic that extends to the Cave Nebula.

Mark


Carole

#1
Wow, as you say it needs to be seen full size to really appreciate it, and at full size it is absolutely stunning.

This is an interesting area full of targets which I imaged once, but found the Lobster in particular very difficult to image, probably because it is a faint(ish) object.

I presume the lighter area in the middle is due to a greater density of stars. 

Can't wait to see the rest of the mosaic.

Carole 

NoelC

Lovely image; the 'Star field' oficianado's will be leaping for joy.
On your sub length; why did you choose 30 seconds? - was that optimum for the illumination?
Even so; at that number of subs I hope you had loads of clear weather to complete your mosaic.

Noel
Swapped telescopes for armchair.

MarkS

Quote from: NoelC
Lovely image; the 'Star field' oficianado's will be leaping for joy.
On your sub length; why did you choose 30 seconds? - was that optimum for the illumination?
Even so; at that number of subs I hope you had loads of clear weather to complete your mosaic.

Noel

Thanks for your comments.  The reason behind the choice of 30seconds is a bone of contention.  The Sony A7S camera applies spatial filtering to any Bulb-mode exposures.  This spatial filtering, often referred to as the Sony "star eater", is designed to deal with hot pixels and colour noise but it's very destructive on stars.  30 seconds is the longest exposure I can do without using Bulb-mode.

Mark

RobertM

Very very nice Mark, I can only counter the stellar overload I'm feeling by seeing it at full scale and at that resolution my monitor is suffering from pixel deficit syndrome :(

Anyone have a cheap 8k monitor lying around that they dont want ?

Robert