M101 - LRGB

[strutsinaction]

Hi

Here's my take on M101 (Pinwheel Galaxy), captured over a couple of nights last week.

Avalon Linear, Tak FSQ85, QSI690

Lum 30x180s 1x1, RGB 20x60s each 2x2, + flats.

Total integration time 2.5hrs.

Captured with SGPro and processed in PI.

I need to capture some more subs think to really start to bring out the details in this faint galaxy, but I'm please so far with the result.

Whilst stretching the Luminance frame I noticed some vertical banding towards the left hand side of the image. I was able to process most of this out but if you look carefully there is still a hint of banding. I'll need to keep my eye on this. I know that some QSI683 users have noticed vertical banding in their lights so it's possible this is the same issue (if it is an issue).

Summary of my PI processing steps/workflow:

- RGB: Calibration/registration/integration with BatchPreprocessing script

- RGB: ChannelCombination

- RGB: Gradient removal with DynamicBackgroundExtraction

- RGB: ColorCalibration

- RGB: Stretch with HistogramTransformation

- RGB: Enhance galaxy features with HDRMultiscaleTransform + lightness mask

- RGB: Noise reduction with ACDNR + lightness mask

- RGB: Colour saturation boost to improve galaxy and star colours using CurvesTransformation + lightness mask

- L: Calibration/registration/integration with BatchPreprocessing script

- L: Gradient removal with DynamicBackgroundExtraction

- L: Stretch with HistogramTransformation

- L: Enhance galaxy features with HDRMultiscaleTransform + lightness mask

- L: Noise reduction with ACDNR + lightness mask

- LRGB: Register L and RGB using StarAlignment

- LRGB: Combine L and RGB with LRGBCombination 

- LRGB: Enhance contrast with CurvesTransformation

- LRGB: Sharpen galaxy with UnsharpMask

- LRGB: Crop with DynamicCrop

Many thanks to Harry Page and his excellent PI videos in helping me get up to speed with these tools!

Regards

John

[Demonperformer]

Nice result so far = looking forward to seeing the result of more data

[strutsinaction]

Thanks, Demon. I just need a few more clear nights like we had last week!

Regards

John

[davedownsouth]

Very nice, I do the same workflow as you, with the exception of your penultimate two:-

- LRGB: Enhance contrast with CurvesTransformation

- LRGB: Sharpen galaxy with UnsharpMask

Will have to have a look into these ,

Dave

[strutsinaction]

Hi Dave

There are a few tweaks to my LRGB workflow that I'm working on:

- Use TGVDenoise or ATrousWaveletTransform for noise reduction rather than ACDNR

- LocalHistogramTransformation after HDR

- Sharpen at the linear stage

Should keep me busy whilst waiting for clear skies to return!

Regards

John

[davedownsouth]

Cheers John, I will look into these in a night or two (hoping to be out with the scope tomorrow / Tuesday ).  Are these new processes detailed in any of Harry's videos, someone else's or have you just found them playing by yourself?

[strutsinaction]

Hi Dave

They are mentioned on Harry's website - Intermediate section and also his LRGB workflow page.

Regards

John

[davedownsouth]

Never gone past the beginners section, probably about time I did. Was thinking I would save this for the long summer night and revisit some of the shots I have taken over the winter period, or rather the busy two weeks in April

Sent from my iPhone using Tapatalk