Triangulum Galaxy (M33) in HaRGB

[turfpit]

Captured 3rd & 5th Jan 2025, 100% and 90% moon, temperature -5°C, 2h integration.

M33_Ha-10x450s_R-35x32s_G-35x27s_B-35x32s.jpg (707.31 KiB) Viewed 1164 times

Hardware: Celestron AVX mount, Vixen 81sd refractor with 0.67x reducer/flattener, Atik 9-slot filter wheel (Altair LRGBHaOiiiSii+ dark filters), Atik 314L+ CCD camera.
Capture: SharpCap
Processing: PixInsight
Data: L 35x10s, R 35x32s, G 35x27s, B35x37s, Ha 10x450s. 50 each darks, 50 each flats, 100 bias.

Processing (PixInsight):

• WBPPP, Calibration/integration with drizzle 1x

• MultiMediaTransform, noise reduction in layer 1 & 2

• ChannelCombination, RGB

• SpectroPhotometricColorCalibration, White reference=Sd Galaxy

• STF + HT, delinearise

• NBRGBCombination script, blend RGB and Ha

• Denoise

• Histogram, CurversTranformation

Dave

[oopfan]

Splendid, Dave. Congratulations!

[turfpit]

Thanks Brian.

Dave

[turfpit]

After some (days) research and experimentation I had discovered enough to use PixelMath to blend the Ha into the Red channel of the RGB image. By using a mask built from the Ha image, the Ha emission areas could be processed while the rest of the image was protected.

With only 2h integration time, the image would be improved with more data.

M33_using_Ha_mask_for_blending.jpg (47.78 KiB) Viewed 1067 times

Processing (PixInsight):

• WBPPP, Calibration/integration with drizzle 1x

• MultiMediaTransform, noise reduction in layer 1 & 2

• ChannelCombination, RGB

• SpectroPhotometricColorCalibration, White reference=Sd Galaxy

• STF + HT, delinearise

• Create mask from Ha image

• Apply Ha_mask to RGB image

• PixelMath to blend Ha into Red channel

• Apply HDRMultiScaleTransform with 7 layers, handles the high dynamic range and stops the core of the galaxy from being blown out with final processing

• Denoise

• Curves stretching and saturation

Masking process to enhance Ha regions.

Ha_mask.JPG (125.08 KiB) Viewed 1067 times

Dave