[RCC] Honest Critique of my M51 Image

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RamonNL avatar
Hi there! I've doing astrophotography quite some time, and the processing gives me headaches. Once you get your head around Pixinsight, a new update is released (mars database for instance) and your whole workflow needs to be altered and you need to figure where it all fits in. 

Anyhow; I'd appreciate some feedback on my M51 Whirlpool Galaxy - AstroBin 

The workflow as WBPP for two stacks, LPro, and L-Ultimate to get the Ha in the core. 

I've been scratching my head on how to process these as I normally use only the NB filter to image nebula, but this was my most recent broadband target. So I've used the blurX and the NoiseX, and the multiscale gradient correction. I've removed the stars, and did a stretch on the LPro as is. The LUltimate was basically more the same, and normally I'd split the channels and process each of these, and stack them together, yet here I removed the stars, did a stretch on the LUltimate stack, added LUltimate and LPro via Pixelmath with a trial and error ratio between these two, and added the stretched the color saturated LPro stars. 

I'd like to make the red more pop, but that is more a trial and error for me, and I always struggle with the stars / object, I try not to overdo the stars (make the object more visible) but that is a tight balance. I'd appreciate any feedback you might have.
John Stone avatar
purple background?  or is my monitor calibration off?
RamonNL avatar
John Stone:
purple background?  or is my monitor calibration off?

I've made worse to put it mildly, but there is indeed a slight purple background.
John Stone avatar
Maybe try a little background neutralization?  (be sure to set the limits to match your actual background levels)
Oscar H. avatar
background neutralization will not remove those dark blue/purple spots

maybe try MGC (with a smaller gradient scale), followed by SPCC, or background neutralization if you don't want to start in the linear phase again (because SPCC requires linear data, if I remember right)
Oscar H. avatar
sorry double post
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