Astrophotography
Welcome to !astrophotography!
We are Lemmy's dedicated astrophotography community!
If you want to see or post pictures of space taken by amateurs using amateur level equipment, this is the place for you!
If you want to learn more about taking astro photos, check out our wiki or our discord!
Please read the rules before you post! It is your responsibility to be aware of current rules. Failure to be aware of current rules may result in your post being removed without warning at moderator discretion.
Rules
- I | Real space images only.
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Astrophotography refers to images of astronomical objects or phenomena exclusively.
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~~Images that show objects or people below the Kármán Line (100km) will be removed.~~ We won't be enforcing this rule for now, but as the community grows eventually we will split and have a separate space for just landscape astro.
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Images must be an accurate representation of a real astronomical object.
- II | Original and Amateur Content Only
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Image posts can only be images that you have captured and processed yourself, or discussion about capturing and/or processing your own images.
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Images acquired from public sources, professional observatories, or other professional services are not allowed.
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If you have done a drastic alteration or reprocessing of a prior submission, you may repost your edit - but only after a minimum of one week has passed.
- III | Post Types
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Image posts are to link directly to the image, not to landing pages, personal galleries, blogs, or professional sites. Link to these in the comments. (AstroBin and Imgur, are allowed)
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Questions are welcome here for the time being.
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Links to blogs, articles or external websites should be interesting and promote discussion about amateur astrophotography.
- IV | Titles
- All image posts should just include include the name of the object being photographed. Extra info such as equipment, it being your first image, or other information should go in a comment along with your acquisition info. Please see this page for more details.
If your post is removed, try reposting with a different title. Don't hesitate to message the mods if you still have questions!
- V | Acquisition and Processing Information
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All submitted images must include acquisition and processing details as a top-level comment. All posts without this information may be given a warning, and if not updated will be removed.
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This includes the telescope, mount, camera, accessories, and any other pieces of equipment you used to capture the image.
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You must also include processing details, i.e. the programs you used and a general rundown of the workflow/processes you used within those programs. “Processed in Photoshop” is not enough.
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The Horsehead Nebula is a dark nebula about 1400ly away from us in the constellation Orion. The Bright star near it is Alnitak, and it one of the stars that makes up Orion's Belt. Because this is one of the brightest stars that people photograph when shooting DSOs, it often can result in unwanted halos, which are present in my RGB filters. I was able to edit the halos out to a level I felt was acceptable (see processing info below), however there still is some color fringing/artifacts on the edge of the halos. Also the bottom left of Alnitak is the Flame Nebula, which is just a nebula that happens to be in the foreground to the horsehead. Captured over 5 nights from February 14-20, 2022 from my Bortle 6 driveway.
Places where I host my other images:
Instagram | Flickr
Equipment:
TPO 6" F/4 Imaging Newtonian
Orion Sirius EQ-G
ZWO ASI1600MM-Pro
Skywatcher Quattro Coma Corrector
ZWO EFW 8x1.25"/31mm
Astronomik LRGB+CLS Filters- 31mm
Astrodon 31mm Ha 5nm, Oiii 3nm, Sii 5nm
Agena 50mm Deluxe Straight-Through Guide Scope
ZWO ASI-120mc for guiding
Moonlite Autofocuser
Acquisition: 12 hours 6 minutes (Camera at Unity Gain, -20°C)
Lum- 251x60"
Ha- 67x300"
Red- 33x90"
Green- 31x60"
Blue- 29x60"
Darks- 30
Flats- 30 per filter
Capture Software:
PixInsight Processing:
BatchPreProcessing
SubframeSelector
StarAlignment
Blink
ImageIntegration
DrizzleIntegration (2x, Var β=1.5)
Linear:
DynamicCrop
Automatic and Dynamic Background extractions
RGB:
ChannelCombination to map monochrome R, G, and B images into a color image
PhotometricColorCalibration
Slight SCNR green
HSV repair
ArcsinhStretch + HistogramTransformation to bring nonlinear
Luminance:
EZ Decon
NoiseXTerminator
ArcsinhStretch + HistogramTransformation to bring nonlinear
Nonlinear:
Created two circle masks per this guide. SCNR + curve tweaks to mitigate the halos from my RGB filters
LRGBCombination with SuperLum
Ungodly amounts of curve transformations to further mitigate the halos, as well as just general curves for lightness, saturation, contrast, hues, etc.
ColorSaturation
Extract L > LRGBCombination for chrominance noise reduction
LocalHistogramEqualization
EZ Star reduction
NoiseGenerator to add noise into reduced star areas
another round of LHE
more curves
CloneStamp to remove a couple of weirdly artifacted stars
even more curves
Resample to 60%
Annotation
Interesting that the halo is square around Alnitak. How’d you do that?
It’s an artifact from the camera. The ASI1600 has microlenses over each pixel on the sensor, which makes this pattern around bright stars
Thanks for the reply. I’ve never heard of such a thing, but I’m a beginner and glad to learn.