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glowingturnip

Pacman Nebula (NGC 281) HaLRGB

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Wakka wakka wakka...

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22x 600s Ha, 11x 420s L, 10x 300s R, G and B, darks flats and bias, equipment as per sig, pixinsight.

 

If I'm honest, I wasn't really feeling the love for this one very much and it's been languishing on my processing shelf for a while - a little too much of it being an amorphous pink blob, coupled with oddly triangular stars (I had issues with coma and collimation when I took it, now resolved, but it meant I was getting tri-lobed guide stars in my OAG and I think that fed through from the guiding to giving me triangular stars in the images.  You can't really see them since Flickr doesn't zoom in enough).  Still, it turned out alright, and I quite like the detail version.

 

The Pacman Nebula (NGC 281) is a bright emission nebula and part of an H II region in the northern constellation of Cassiopeia and is part of the Milky Way's Perseus Spiral Arm.  The nebulosity is associated with an open star cluster, several Bok globules and a bright quintuple star system.  It lies approximately 9200 light years away.

 

Pac-Man was designed to have no ending – as long as at least one life was left, the game should be able to go on indefinitely. However, a bug keeps this from happening - an 8-bit arithmetic overflow error on level 256 would mean that the game would try to draw 256 fruits on the screen rather than the maximum of 8 that it would normally draw.  This corrupts the bottom of the screen and the entire right half of the maze with seemingly random symbols and tiles, overwriting the values of edible dots which makes it impossible to eat enough dots to beat the level. Because this effectively ends the game, this "split-screen" level is often referred to as the "kill screen".  A perfect Pac-Man game occurs when the player achieves the maximum possible score on the first 255 levels (by eating every possible dot, power pellet, fruit, and enemy) without losing a single life, and using all extra lives to score as many points as possible on Level 256.

Pac-Man_split-screen_kill_screen.png

 

This was actually my second attempt at this target - this was my first one, with a modded DSLR - actually not too bad:

23154211176_64b904b027_c.jpg

 

Hope you enjoy !  Comments and cc welcome.

 

Stuart

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    • By alan4908
      A crop of the narrow band NGC281 image illustrating the detail of the central region.
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