M33 - Hypercam 183 OSC (Tom Gray)

M33 - Hypercam 183 OSC

Revision title: Processed in Nebulosity 4

At last a clear night with reasonable seeing, and an opportunity to try out my new camera (Altair Hypercam 183C pro) at longer focal lengths using my 8" SCT with f3.3 focal reducer. I collected 2 hours RAW data of M33, binned 2x2, in Nebulosity using a small dither in PHD2 guiding (~RMS 1").

Data were pre-processed (10 darks, 0 flats), debayered, aligned and stacked in Nebulosity, which is where my problems began. My first efforts turned out with very strange colour, a blue core and brown star streams - it seems that I needed to apply offsets to the RGGB color matrix. Processing was completed in Startools using defaults, although some vignetting, gradients and dust motes remain (I must produce and apply flat frames for this camera). I have uploaded the binned image further reduced by 50% to save disk space.

I am still not sure what gain settings to use (30/3000 depending on the software you use) in this image, which produced a tight histogram, and appeared to reduce noise. I had to stretch the data quite aggressively to bring out the fainter outer arms; if anyone has guidance on the correct settings I would be grateful.

Overall, I'm quite pleased with the outcome - depth and resolution are better than my DSI 3 pro mono (1.4Mpx) camera, as expected, although some star distortion at the field edges; I just used my Meade 15mm T thread to focal reducer adapter, and need to compare the required backspace. Progress, and above all enjoyment from sitting out under a cold dark clear sky.

Original
Final
B

B

Title: Processed in Nebulosity 4

Description: I think this is SO much better - same data processed in Nebulosity 4 with synthetic flat field, DDP, curves and gentle sharpening / noise reduction. I feel the image is much more natural, shows off the colour and detail better and the synthetic flats are surprisingly good. I'm uploading this as a full resolution image with no further reduction (original 2x2 binned data), so you can explore in more detail. What do you think?

Uploaded: ...

The OSC Club (One Shot Camera)
UK Astro-Imaging
Schmidt-Cassegrain Telescope (SCT) Imagers
Altair Astro 183 M/C Hypercams

	Distinct awarded users	Total awarded images
Image of the day
Top picks
Top pick nominations

	Image of the day	Top pick	Top pick nominations	Total submitted
Deep sky
Solar system
Extremely wide field
Star trails
Northern lights
Noctilucent clouds
Landscape

	Image of the day	Top pick	Top pick nominations	Total submitted
Backyard
Traveller
Own remote observatory
Amateur hosting facility
Public amaeteur data
Professional, scientific grade data
Mix of multiple sources
Other
Unknown

Submitted The date and time when you submitted this image for IOTD/TP consideration.	...
Views by Submitters (available since September 19th, 2023) Every image is assigned to 50% of available Submitters. In the event that at least 80% of them don't view the image before its time in the IOTD/TP process expires, it's assigned to the other 50% of Submitters and the process begins anew.
Promotions by Submitters When 3 distinct Submitters promote the image, it moves on to the next stage of the process: evaluation for Top Pick status. This requirement, in addition to anonymization of images and distribution to only a subset of them, prevents biases and ensures that the best images are selected.
Promotions by Reviewers When 3 distinct Reviewers promote the image, it moves on to the next stage of the process: evaluation for IOTD status.
Early dismissal Staff members have a lot of images to inspect on a daily basis, and they can dismiss images if they believe they don't meet the requirements for IOTD/TP selection. If an image is dismissed 5 times, it's removed from the process. This streamlines the process and ensures that any bias present in promotions could be overruled by other staff members.

Status	Advanced success
Started	...
Astrometry.net job	5380784
PixInsight job	85I16MGKGXEZ2QE2SDKTMQRRCRABVXL0
PixInsight queue size	n/a
PixInsight stage	TASK_LOG

RA (center)	01h33m50s.900
RA (top/left)	01h35m38s.753
RA (top/right)	01h32m22s.714
RA (bottom/right)	01h32m01s.345
RA (bottom/left)	01h35m16s.724

Dec (center)	+30°39′12″.10
Dec (top/left)	+30°49′18″.38
Dec (top/right)	+30°56′27″.54
Dec (bottom/right)	+30°28′56″.44
Dec (bottom/left)	+30°21′48″.89

Image Index:

Contribution Index (beta):