What's in the night sky for December 2025?

 What’s in the night sky for December 2025?

December 2025 features the Geminids meteor shower peaking around December 14th, the Super Cold Moon on December 4th, and the winter solstice on December 21st. Key celestial objects to find are bright Jupiter in the east and Saturn in the west, with Mercury visible in the morning sky before its greatest western elongation on the 7th. 

Meteor showers

• Geminids: A major highlight, peaking around December 14th with up to 120 meteors per hour possible.
• Astrophotography tip: The peak occurs when the Moon is a thin crescent, providing excellent dark skies for capturing this shower.
• The Ursids:  Also active, peaking around December 22nd with lower rates (up to 10 meteors per hour). 

Planets

• Jupiter: The brightest object in the evening sky, visible in the east after sunset and moving towards opposition in January.
• Saturn: Visible in the south-west in the early evening. It sets earlier in the month as December progresses.
• Astrophotography tip: Look for the Pleiades and Hyades star clusters in the constellation Taurus
• Mercury: Best viewed in the pre-dawn hours in the southeastern sky, with its greatest western elongation on December 7th.
• Neptune: Will require binoculars or a telescope to spot, located near Saturn in the constellation Pisces. 

Other events

• Super cold moon: The Full Moon occurs on December 4th and is a Supermoon, meaning it appears larger and brighter than a typical Full Moon.
• Winter Solstice: Occurs on December 21st, marking the shortest day of the year in the Northern Hemisphere.
• Andromeda Galaxy: Can be seen in the southern sky on darker nights. 

Astrophotography tips

• Meteor showers: The Geminid meteor shower is ideal for photography due to its high rate and the favorable moon phase.
• Planets: Consider capturing Jupiter or Saturn, but remember they are best viewed from a location with less light pollution.
• Deep sky objects: The Andromeda Galaxy and the Pleiades star cluster are excellent targets for astrophotography, but require darker skies. 

1st Dec		This blog gives some excellent astrophotography targets for the month: https://starwalk.space/en/news/december-deep-sky-objects
2nd	Ganymede’s shadow crosses Jupiter’s disc 0610 – 0925.	This website adds further to the calendar details shared here: https://starwalk.space/en/news/night-sky-tonight-december
4th	98% lit waxing gibbous moon occults M45 Pleiades from around 0300. Uranus is 4.6” south of the moon at this time. Full moon at 2315 – a perigee full moon today	If you want to image Orion during December, this website gives so good targets to try and image or visually observe: https://elanvalley.org.uk/uncategorized/eyes-on-the-night-sky-december-2025/
6th	Ganymede reappears from behind Jupiter around 0235
7th	Mercury reaches greatest western elongation – 20.7 degrees west of the sun in the morning sky - meaning it is at its farthest point from the Sun from our perspective.  87% lit waning gibbous moon this evening – sitting 3.5 degrees from Jupiter around 1900.	The ideal time for spotting Mercury will be just before dawn on 7 December, looking to the east. However, its not prudent to observe Mercury through a telescope as it will be very close to the sun and you risk pointing your scope directly at the sun as it rises
8th	Titan transits Saturn between 1730 – 2350 Callisto begins transit of Jupiter between 0210 and 0620
9th	Low altitude views of Saturn around 2348. Should see Titan and Rhea as well.
10th	Regulus is occulted by the 66% lit waning gibbous moon around 0718 during brightening dawn twilight
12th	Ganymede is eclipsed by Jupiter’s shadow around 2355 – reappearing around 0558 on 13th.
14th	Peak of Geminid meteor shower – with little interference from the moon (in a waning crescent phase)
16th	Titan occulted by Jupiter’s globe – 1623. Reappears 2205. Callisto occulted at 0744. Ganymede completes transit of planet – 1800 to 1950
21st	December Solstice
22nd	Peak of Ursid meteor shower
23rd	Ganymede’s shadow transits Jupiter’s disc 1947 to 2308. Ganymede does its transit 2120 to 2309
24th	Titan transits Saturn 1625 to 2305 Io, Callisto all transit as Jupiter rises.
25th	Watch out for Santa and his sleigh transiting everything after dark!
30th	Ganymede’s shadow crosses Jupiter’s disc 2158 to 0123 on 31st. Ganymede itself transits 2300 to 0228 on 31st.

Sources "Sky at Night" and "High Scientific"

Imaging session on NGC 1499 The California Nebula

 A Night in the Back Garden Under the Stars

Target: NGC 1499, the California Nebula
Mood: Mischievous Backyard Astronomer

There are glamorous observatories on mountaintops… and then there’s my back garden: a patch of grass with a steep incline above it, and a band of trees that act like they own the southern horizon. A slice of sky that runs from the northwest around to the east. Everything else? Hidden behind a wall of woodland darkness, as if the universe pulled a curtain halfway across the stage. Frustrating? Absolutely. But also, oddly charming.

I often joke that imaging from the back garden is lazy astronomy—as if I’m somehow cheating the grand tradition of freezing atop windswept hillside car parks. Yet, every time I do it, I feel delightfully wicked, like a child raiding the biscuit tin when no one was watching. No packing the car. No driving at ungodly hours. Instead, I get to nip inside for a cuppa or catch a bit of TV while the mount gently whirrs away outside under the stars. The nightscape? Hooting owls, prowling cats, and the occasional fox strolling down from the woodland like it’s popping by to check on my guiding graph.

Shamefully luxurious behaviour… and I adore it.

A few months ago, in the spirit of “back garden decadence,” I upgraded the observing area. I installed three perfectly spaced patio slabs for my tripod. Then I brought some colourful 12mm children’s foam jigsaw mats to lay across the decking. Functional? Extremely. The deck turns into something between a skating rink and a death trap this time of year, and those mats keep me from performing accidental gymnastic routines while carrying expensive optics.

So, a few weeks back, on a crisp moonless night, I finally aimed for NGC 1499. From the kitchen table (aka mission control), I could see the mount through the window while stirring hot soup and basking in the warm red glow of my head torch. I seem to feel the cold more these days—an unexpected betrayal, considering how many winters, long ago, I spent stomping through snowfields or dangling from an ice axe on frozen waterfalls. Back garden astrophotography, therefore, feels like a snug loophole in the universe’s rules.

Despite the suburban light pollution, I managed several solid hours on the nebula over two nights. Below is the kit list for anyone curious—or for future me, when I inevitably forget which power bank ran what.

 

Equipment

• Canon 800D with clip-in Optolong L-eNhance filter
• William Optics Zenithstar 61II with 61A field flattener
• Sky-Watcher EQM-35 Pro mount
• Guiding: ASIAir Mini + ZWO 120mm guide cam + RVO 32mm guide scope
• Celestron Lithium Pro power tank
• Dew bands on main and guide scope
• Two small power banks dedicated to dew bands
• Dummy battery + power bank for the Canon 800D
• MSM green laser pen with polar alignment adapter
• Sky-Watcher right-angled polar viewer
• Neewer intervalometer

 

Imaging Data

Night One

• 30 × 360" lights
• ISO 1600
• 12 darks
• 20 bias
• 30 flats

Night Two

• 43 × 360" lights
• ISO 1600
• 15 darks
• 20 bias
• 30 flats

Guiding behaved surprisingly well for an un-serviced, third-hand mount. The RA axis is a little stiff – a bit like me – a ‘sometimes’ reluctant older bloke getting out of a comfortable chair. Nothing disastrous with guiding - RA hovered around 0.80, DEC around 0.90. Honestly, not bad considering I’m still getting acquainted with the ASIAir Mini and its app.

This was my very first rough post edit of the data and I’ll update this post further once I process the images properly; and I will share my full workflow - warts, wonders, and all. Stay tuned for a hopefully better edited California Nebula in all its crimson glory!

As always, collecting thge data is the easy bit

Post editing is a dark, dark art though! 

I am still getting to grips with how SIRIL v1.2.6 works. Throw in GraXpert and then also learning how to use Affinity Photo 2 - and it all fries my brain.

As always, the same issues are cropping up in my post editing work flow - over stretching, noise etc. 

On the bright side? Two years ago I knew absolutely nothing about photography, astrophotography, basic astronomy - so I am making some progress - all be it is small baby steps! 

Equipment review: - A review of the ASIair Mini from ZWO

 New to this blog, then welcome, and after reading this post why not stop off here and find out more about me and this blog at https://undersouthwestskies.blogspot.com/2025/01/welcome-to-my-new-astronomyastrophotogr.html

Some pieces of equipment feel like they earn their place in your kit bag. Others, feel like they deserve a small shrine to techie ingenuity!

My ASIair Mini is one such beastie which needs a shrine! A palm sized marvel of technology that punches above its weight. Equal parts tech wizardry and control tower, in this blog today, I review my ASIair mini, 9 months on from purchasing it. The good, the bad and occasionally the plain baffling! So, I’ll cover

·       A very quick tour of its key features

·       Outline its standout advantages

·       Examine its quirks, drawbacks and disadvantages

·       Review what other users and reviewers say about it

·       Who I think the ASIair Mini suits

And, if you are new to the ASIair Mini cosmos, you might want to also check out my beginner’s tutorial to setting up and using the ASIair mini on your own rig.

https://undersouthwestskies.blogspot.com/2025/02/beginners-guide-to-using-autoguiding.html

Copyright for all images  - Alan Dyer on Cloudy Nights forum

So, let’s start with:

Features I like

Hardware & connectivity – is it the Swiss army knife of astrophotography hubs? Let’s find out.

• Compact size & light weight. It really does fit in the palm of my hand and is lighter than many eyepieces I own
• Made of CNC-machined aluminium, giving a sturdy, dust/dew-resistant body. It just looks compact, elegant and efficient (I’m so shallow!). A ’premium gear’ vibe.
• Built-in WiFi antenna supporting 2.4GHz and 5GHz for wireless control from phone/tablet.
• USB Type-C port (for e.g. connecting to computer or export) and 4 × USB 2.0 ports.
• Four 12V DC output ports (to power accessories such as camera, dew heaters) and a DSLR shutter release port.
• Power monitoring: A mini mission-control in the palm of your hand - the unit allows monitoring of input voltage/current, and reports temperature, devices connected etc. Not just smart, its ‘thoughtfully’ smart!
• Software/firmware features: Plate-solving for alignment, polar-alignment routines, focusing assistant, multi-target planning, image stacking on-device (for supported cameras) etc.
• Storage: Internal eMMC storage (e.g., ~32 GB) for saving captures. But you can use a usb stick in one of the usb ports as well

 

Workflow & usability

Tired of a spaghetti mess of cables, laptops, power bricks? The Mini may well feel like a breath of fresh night time air for you!

• You can use a smartphone or tablet (iOS or Android) to control the camera, mount, guiding, focus, filter wheel etc. Moreover, I can do it from the kitchen! Make a cuppa, keep warm, monitor everything happening outside – its living the dream!
• All-in-one imaging hub: The Mini replaces a laptop + multiple control boxes + messy cables with a simpler one-box solution. A simple portable rig without a power-hungry laptop etc – brilliant.
• Good WiFi range: I can go back in the house, sit in the kitchen and it still works.
• Imaging feature set: The app supports tasks like focusing (with curves/HFD), plate-solving, dithering, calibration frames, filter switching, auto-guiding, multi-target sessions. Confession time – I haven’t even scraped the surface of some of these functions yet! I literally learn something new every time I use it!

 

Here is my take on advantages, but I also researched this on some of the popular forum threads.

Advantages (What the Mini does well)

1.      Simplified setup & workflow
It took me a couple of sessions to work out the basics. Like deciphering hieroglyphs, but that maybe because I’m a tad dim. It does make astrophotography much easier — especially for deep-sky imaging – centralising everything and reducing cable clutter, eliminating the need for a laptop etc. It’s probably the simplest and most user-friendly controller around.

2.      Portability & power efficiency
So compact and low-power compared to a full laptop – brilliant for my “grab-and-go” setups. The aluminium body makes it robust for field use and a good WiFi range gives flexibility in positioning. It is easy to switch between my two rigs. A backpacking astronomer’s dream!  

3.      Integrated control & monitoring
Many reviewers and users commented on the fact that having power-ports, USB ports, monitoring of voltage/current etc means you can run camera, mount, focuser, heaters etc from one hub — reducing separate controllers. It’s a conductor orchestrating your astrophotography symphony. Now, I haven’t done all this yet – mine acts as a hub connecting the mount, guide camera and DSLR camera (which it does easily). I run dew band heaters from a separate power pack. Autoguiding and dithering run very well by the way. Basically, it has plenty of bells and whistles for beginners new to astrophotography to be getting on with.

4.      Strong value
Weigh up its capabilities against its price and its real value for money. The price point relative to capability is often mentioned in reviews. I got mine bundled with the ZWO 120mm mini guide cam and also a guide scope.

5.      Good support for ZWO ecosystem
If you already own ZWO cameras, focusers, filter wheels etc, then the integration is generally ‘plug and play’ heaven – seamless integration.

 

What comes in the box 

Now there are disadvantages with the ASIair Mini; its less shiny side is where it gets a little tricky – some are to do with the unit itself but many are to do with the control app. No product is flawless and the Mini is no exception.  

Disadvantages / Limitations (What to watch out for)

No product is perfect, and the Mini has several caveats noted by users & reviewers and me for that matter.

1.      Hardware compromises (to achieve “Mini” size/price)

o   The USB ports are all USB-2.0, not USB-3.0. and some reviewers note that full frame cameras will not work with the live stacking feature.”

o   The unit lacks some features of the larger ASIAIR Plus/Pro models: e.g., there is no Ethernet port.

o   Because of its simplified / cost-cut design, some more advanced features and high-end workflows may be constrained. Not ideal then for ultra-demanding setups.

2.      Ecosystem lock-in
A frequent criticism: you are somewhat locked into the ZWO ecosystem (cameras, focusers, filter wheels) if you want full functionality. The Mini plays nicest with its own family! Software not including drivers for cameras, focusers, or filter wheels from competing manufacturers and where it does occasionally occur, you aren’t guaranteed full, smooth integration. My tip? Do a compatibility check before buying if you have non-ZWO gear already.  

3.      Software/firmware stability & glitches
Some users report bugs, wireless disconnects, or setup quirks. And this is a major issue I feel – put it this way, once I got mine set up and working, I switched off automatic update on the app. Why? Some of the app upgrade releases have on occasions come with bugs, stability issues, random disconnections and more. It isn’t often but it is frustrating when it happens.

4.      Power supply caution
The Mini needs a proper power source – ideally 12V/5A. Underpower it and you risk instability. A power bank of say 12V/1.5 could endanger the electrical integrity of the ASIair. Hence, I run dew band heaters off a separate power bank, just to play safe.

5.      Not optimal for very high-end / high-speed camera workflows
Running a large camera sensor? Doing high speed planetary imaging? The USB-2 ports become a bottleneck if you are trying to connect many accessories such as camera+guide cam+focuser+filter wheel+USB stick.  The Mini may struggle in workflows that demand very fast data transfer, live-stacking full-frame cameras etc.

6.      Avoid “cheap” cables/adapters that may cause voltage drop or mis-outputs.

7.      App/User-interface quirks

o   Some beginner users find the app somewhat unintuitive initially and mention that the downloadable PDF manual is lacking specifics, outdated and rather vague on some important aspects. I really had to rely on YouTube experts and then draw up my own guide sheet when first using it as there was so much to take in. I strongly urge you to check out my other post with its videos and ‘cheat sheet’.

o    Plate solving bugs with the ASIAIR mini crop up - completely failing GoTo – is one I occasionally experience it’s as frustrating. The telescope develops schizophrenia, traversing in a seemingly random direction, confirming a plate-solve on your target but pointing to a completely different area of the cosmos. Makes me a very confused stargazer at times!  My solutions have been to check the sequence of powering mount vs the Mini. (Turn on the ASIAIR Mini first, then mount/power gear. Also, make sure plate-solving and GOTO are correctly configured; check mount parameter settings, orientation, and that image orientation is correct.)

o   Freeze firmware updates if you have a working setup. Some users recommend not updating immediately after app/software releases or waiting to see feedback in forums after a release. As I have already said, miner is permanently frozen on one version and I haven’t updated it since, with no ill effect thus far.

 

Recommendations: What rigs the ASIAIR Mini suits (and which it doesn’t)

OK, getting into dangerous territory now, as I am still a beginner to this, but here are my thoughts:

Best suited rigs

The Mini is particularly well suited to:

• Portable / field rigs: especially “grab-and-go” setups where you want minimal cables, quick setup, remote control from your phone/tablet.
• Deep-sky imaging with mid-sized sensors: If you have a camera of moderate size (e.g., APS-C or smaller), and you are doing exposures of a few minutes, the Mini will work well as the hub controlling mount guiding, camera, focuser, filter wheel.
• ZWO ecosystem users: If your camera, focuser, filter wheel etc are ZWO branded, the integration will be smooth and you’ll benefit from the Mini’s streamlined workflow.
• Simplified rigs / beginners: For someone looking to avoid the complexity of a full PC + multiple control software, the Mini gives a more “plug-and-play” experience and is a good choice for those who want quick results. No headaches here!

A very similar set up to my own rig

Less suited rigs / when to consider something bigger

You might consider a more advanced controller (or a full PC) instead of the Mini when:

• You are using large-format sensors (full-frame or very high-megapixel cameras), or doing high-speed imaging (e.g., planetary, lucky imaging) where USB 3.0, more bandwidth, and faster I/O matter.
• Your gear is heterogeneous, i.e., a mix of non-ZWO cameras/focusers/filter wheels, or if you want maximal flexibility across brands. The Mini may limit you due to driver/support constraints.
• You need advanced/custom scripting, very complex automation, or run multiple heavy tasks (e.g., very large mosaics, heavy live-stacking) where a full PC might be more robust.
• Your power supply situation is marginal or you are using a lot of accessories drawing from the Mini’s 12 V outputs: you’ll need to ensure a good battery/power rig, otherwise you might face instability.

My verdict

If you said “Steve, you are biased about this piece of equipment”, I think that would be a fair challenge. I think the ASIair Mini has made my astrophotography real fun. It has stripped away complexity, clutter and laptops! A very capable, well-designed controller for deep-sky astrophotography, uncomplicated, portable simplicity and wireless control. I think it fits the bill for a first standard deep sky astro rig with an APS-C size camera, smaller refractor, decent mount or larger tracker. From my perspective, it is excellent value. Now, as a beginner, I know I will not be upgrading my kit until I have better understood and mastered some of the post editing skills, so I’ll be keeping the Mini for some time to come. A trusted co-pilot in my cosmic adventures.

On the other hand, if your ambitions are “enthusiast/pro” level with large sensors, many accessories and multiple brands, you might consider stepping up (e.g., to ASIAIR Plus/Pro or a dedicated mini-PC) so you don’t outgrow the device. And, don’t forget, you are locked into the ZWO ecosystem regarding other accessories such as focusers, filter wheels etc.

Bottom line – The ASIair Mini is a pocket-sized computer for your astro rig – smart, efficient and on the whole quietly brilliant. It won’t do everything, but what it does do, it does exceptionally well in my experience.

The ZWO ASIair Mini teamed with my Canon 800D, a RVO 32mm guide scope with ZWO 120mm mini guide cam

and below the rig mounted on my EQM-35-PRO mount 

This review gives some more details that you may find useful: https://www.cloudynights.com/articles/astro-gear-today/reviews/zwo%E2%80%99s-new-asiair-mini-reviewed-r4669/

Beginner’s Guide to Post-Editing a Stacked Comet Image in Affinity Photo V2

 Beginner’s Guide to Post-Editing a Stacked Comet Image in Affinity Photo V2

With the free of Affinity Photo 3, I know many astrophotographers are considering the switch across from Photoshop. I have been using Affinity Photo for two years now and this is my workflow for processing a comet image.

Tools Used:

·       Develop Persona (for RAW files)

·       Photo Persona (main editing workspace)

·       Layers, Masks, Curves, Levels, HSL, and Noise Reduction filters

If you want to know how to capture a comet image - these previous posts may help: 

https://undersouthwestskies.blogspot.com/2025/10/a-beginners-guide-to-photographing.html

https://undersouthwestskies.blogspot.com/2025/11/imaging-session-chasing-comet-lemmon.html 

https://undersouthwestskies.blogspot.com/2025/11/beginner-tutorial-how-to-stack-comet.html

 

Workflow

If working from a single RAW file:

Start at Step 1 (Develop Persona).

If importing a stacked FITS/TIFF image:

Open the file directly into Photo Persona, but still follow the adjustments from Step 2 onward.

 

1. Prepare Your Image in the Develop Persona (RAW files only)

These steps set a clean starting point before moving to the main editor.

• Exposure: Pull back highlights if the comet nucleus looks blown out.
• Black point: Increase slightly to deepen the sky background.
• Contrast & Clarity: Keep very low — high values exaggerate noise.
• White Balance: Neutral or slightly cool for a natural comet colour.
• Lens Corrections: Enable chromatic aberration and vignetting corrections.

Click “Develop” to enter the Photo Persona.

 

2. Clean Up the Background & Frame the Image

This stage sets your sky background and composition before isolating the comet.

a. Crop & Rotate

Straighten the frame and position the comet creatively (e.g., rule of thirds or aligning the tail diagonally).

b. Duplicate the Base Layer

Right-click → Duplicate.
Having a backup layer is always useful.

c. Remove Gradients / Light Pollution

Choose one approach:

• Manual tools:
  Use the Inpainting Brush or Clone Tool to smooth bright areas near the horizon.
• Curves + Mask method:
• Add a Curves Adjustment Layer
• Invert its mask
• Paint white on the mask where gradients occur
• Gently darken those regions
• External tool:
  Software like GraXpert often produces excellent gradient removal results, then you re-import the cleaned image into Affinity.

This gives you a clean sky to work with before enhancing the comet.

 

3. Isolate and Enhance the Comet

This step ensures that adjustments to the comet don’t accidentally affect the stars or sky.

a. Select the Comet

Use the Selection Brush Tool or Freehand/Pen Tool to outline the comet and tail.

b. Feather the Selection

About 10–30 px, depending on image resolution.

c. Create a Masked Layer

Right-click → New Layer with Mask.
Now you have a specific “Comet Layer” for targeted editing.

d. Enhance the Comet

• Curves: Lift midtones and highlights slightly to brighten the tail and nucleus.
• HSL:
• Slight saturation boost (5–10%)
• Subtle hue shifts if you want to emphasise green/blue tones in the coma
• Detail Enhancement:
  Use Unsharp Mask or the Clarity filter, gently:
• Radius: 1–2 px
• Amount: ≤ 30%

This should bring out tail structure without creating halos.

 

Comet Lemmon october 2025

Images snatched between cloud breaks 

4. Control Stars & Background

Comets often benefit from reducing the prominence of surrounding stars.

Option A — Using Plugins

If you have the James Ritson astrophotography macros/plugins for Affinity (or similar tools), apply the star-reduction macro here.

Option B — Manual Star Softening

A simple technique: 

1. Duplicate your background layer.
2. Apply Gaussian Blur (≈ 3–5 px).
3. Change the layer’s Blend Mode to Darken or Soft Light.
4. Mask out the comet so it remains bright.

This subtly reduces star intensity without removing them.

Optional: Boost Star Colour

Use HSL or Selective Colour, applied through a mask targeting only the star field.
Increase saturation very gently for natural, pleasing star colours.

 

5. Final Colour & Contrast Refinements

These global adjustments tie the whole image together.

• Curves: Add a subtle S-curve to improve overall contrast.
• HSL or Selective Colour:
  Adjust the sky tone — aim for a natural, slightly cool deep grey/blue-grey rather than pure black.
• Levels:
  Bring the black point inward carefully. Avoid clipping faint comet tails or dust structures.

 

6. Noise Reduction & Final Polish

Noise typically increases after gradient removal and enhancement steps, so save this for last.

1. Merge a copy of the visible layers (Right-click → Merge Visible).
2. Apply Reduce Noise (Filters → Noise → Reduce Noise):
• Luminance: ~30–50%
• Colour: ~20–40%
• Preserve Details: ON

You can also use a mask to apply noise reduction only to the background, keeping the comet sharp.

 

A second version of my Comet Lemmon image 

7. Exporting Your Final Image

Choose output format based on purpose:

• TIFF (16-bit): Best for scientific, archival, or further processing.
• PNG or JPEG: Ideal for sharing online (JPEG quality ~95%).
• Use sRGB profile for web posting.

 

Optional Advanced Techniques

• Comet/Star Combination:
  Blend a comet-tracked stack with a star-tracked stack using Lighten or Screen blend modes for the best of both worlds.
• Affinity Astrophotography Stack (V2.4+):
  Affinity now supports astrophotography stacking natively, including star alignment and median stacking — useful for producing a cleaner starting point before editing.

 

Final Thoughts

Affinity Photo V2 is a powerful, affordable tool for comet processing, and once you get comfortable with masking and adjustment layers, you’ll find it capable of professional-quality results.
Working slowly, keeping edits subtle, and masking carefully will help your comet images look clean, natural, and visually striking — perfect for sharing or printing.

Of course, as a beginner myself, Affinity Photo is still something I have to master. Masking is my Achilles heel – rather frustratingly!

As always, do you have a different work flow? What do you do differently? What additional tips would you add in here? Drop us your tips, thoughts, observations in the box below. 

Clear skies and take care out there, and as always, have plenty of fun! 

Steve 

Equipment review: Samyang 135mm f/2 (Manual Focus) — My Go-To Wide-Field Astro Lens

 First visit to this astronomy/astrophotography blog? Well, firstly a warm welcome to you and thanks for stopping by. If you want to find out more about me and this blog, why not visit my introductory page at https://undersouthwestskies.blogspot.com/2025/01/welcome-to-my-new-astronomyastrophotogr.html  You can also browse other posts by using the search bar or the blog post list on the right hand side and I'd really like to hear from you via the comment boxes. Drop me a tip, an observation or a question. Take care and clear skies to you.  Steve 

Samyang 135mm f/2 (Manual Focus) — My Go-To Wide-Field Astro Lens

If you love photographing the night sky but don’t want to remortgage your house to do it, then the Samyang 135mm f/2 could be your new favourite piece of glass. I like to keep my setup simple, reliable, and travel-friendly and I’ve been using this lens for more than two years, teamed with my Canon 800D; it’s my go-to companion for wide-field astrophotography whether it be to frame a nebula or sweep across the Milky way without lugging a telescope around.  

After two years of late nights, frosty fingers, and countless star fields, I thought it was time to share my thoughts. What makes this lens such a hit among astrophotographers? How does it perform? What are its strengths and pitfalls? And, what are the trade-offs you should know before you buy? Let’s find out.

In this review, I’ll:

• Walk through the key features
• Highlight the strengths
• Weigh up the downsides
• And wrap up with my honest verdict

My lightweight, portable wide-field astro rig incorporating the samyang 135mm f/2 lens with my canon 800D DSLR 

Overview

The Samyang 135mm f/2 is a bit of a cult classic in astrophotography circles — a manual-focus, full-frame compatible prime lens that delivers serious optical performance without burning a hole in your wallet. It’s available in several mounts (Canon EF, Nikon F, Sony E, and more), and photographers often praise it for its sharpness and contrast at a surprisingly modest price.

Think of it as the astrophotography world’s version of a dependable old telescope — it doesn’t boast flashy electronics or fancy features, but what it does offer is clarity, consistency, and a ton of light-gathering power.

At f/2, it’s a light vacuum, pulling in photons like a cosmic magnet. Even at f/2.8, stars in the corners remain crisp and clean, with minimal chromatic aberration or distortion. For me, it’s become a workhorse lens that simply delivers, night after night.

Why It Shines for Astrophotography

Here’s what I think makes the Samyang 135mm such a gem for capturing the night sky:

1. A fast f/2 aperture — a real light bucket.
Speed is everything in astrophotography. The faster the lens, the less time you need to collect light — and that means fewer tracking errors, shorter subs, and sharper stars.

2. Excellent corner-to-corner sharpness.
Even wide open, stars stay tight and well-defined all the way to the edges. Many lenses struggle with soft or warped corners, but this one keeps its composure beautifully.

3. Great value for money.
Compared to astrographs or premium telescopes with similar optical performance, the Samyang 135mm is an absolute bargain. You get premium-level sharpness at a fraction of the price — ideal for beginners or anyone building a portable setup.

4. Manual focus — an advantage, not a drawback.
In astrophotography, autofocus is about as useful as sunglasses at midnight. Manual focus gives you full control, and with a simple Bahtinov mask (you can easily 3D-print or order one online), you can achieve razor-sharp stars every time.

5. Plenty of compatible accessories.
This lens is a tinkerer's dream. You can attach support rings, dovetails, red-dot finders, guide scopes, ASIAir units — even a ZWO EAF focuser if you want to automate your setup. These can be 3D printed – if you are lucky enough to own one – or easily purchased off various shopping websites

6. Perfectly balanced focal length.
At 135mm, you’re right in that sweet spot between wide-field and close-up imaging. Large nebulae, Milky Way segments, star fields — it handles them all beautifully. On crop-sensor cameras, the extra reach (around 200mm equivalent) makes it even more versatile.

7. Impressively low chromatic aberration.
Colour fringing on stars is minimal — a big win if you’re after clean, natural-looking results, especially in narrowband imaging.

8. Portable and travel-friendly.
Pair it with a small star tracker like the Sky-Watcher Star Adventurer, and you’ve got a grab-and-go setup that can fit in a backpack. No observatory required — just clear skies and a bit of patience.

9. When using a cooled astro camera (mono/colour) with filter wheel etc, the Samyang 135mm f/2 can serve as a fast, relatively “short‐telescope” field of view—great for large nebulae, wide star fields, Milky Way segments in narrowband or broadband. Because many astro-cameras have large sensors, the good corner performance is very useful.

copyright astropical space

Disadvantages (a.k.a. “The Fine Print”)

No lens is perfect — and the Samyang 135mm does have a few quirks worth knowing. Think of these not as deal-breakers, but as “lessons from the field.”

1. Vignetting at wide apertures.
At f/2, corners can lose up to 40% brightness. It’s nothing a good set of flat frames (or stopping down to f/2.8) can’t fix, but it’s worth planning for.

2. Sample variation.
Quality control can be hit or miss. Some copies are pin-sharp, others have slight decentring or coma issues. Buy from a reputable dealer with a solid return policy.

3. Infinity focus quirks.
When used with astro cameras and adaptors, the lens doesn’t always hit true infinity focus right at the mark (particularly when using M42/T2 adapters, it seems). You may need to experiment a little with spacers or back-focus distance.

4. No weather sealing or stabilisation.
Not a huge issue for astrophotography, but if you’re shooting on cold or damp nights, dew control is essential. A lens heater or dew strap is your friend here.

5. Focusing precision required.
At f/2, the depth of field is razor-thin. Even a hair off perfect focus can soften your stars. Take your time, use Live View zoom, or better yet — a Bahtinov mask.

6. Middle-ground focal length.
Some users find 135mm to be neither wide enough for sweeping Milky Way shots nor long enough for small galaxies. Personally, I find it a perfect “in-between” — but it depends on your targets.

7. Back-focus spacing issues (for astro cameras).
When used with filter drawers or adaptors, incorrect spacing can throw off sharpness or infinity focus. It’s worth double-checking your measurements — the devil really is in the millimetres.

8. Heavier than you’d expect.
At first glance, it looks compact, but it’s got a bit of heft to it. Still, when you balance it properly on a tracker, it’s more than manageable.

My Verdict

After two years of use, I can confidently say, that based on personal experiences, the Samyang 135mm f/2 must be one of the best bang-for-your-buck astrophotography lenses out there. It’s sharp, fast, and remarkably capable for its price. A compelling option for beginners on a limited budget who want a relatively fast, high-quality lens.

Sure, it asks for a little patience — careful focusing, calibration flats, and the occasional bit of back-focus tinkering. But if you’re willing to put in that small effort, it rewards you with breathtaking wide-field images.

Copyright Stellar Discovery 

To summarise:

• Highly recommended if you’re using a DSLR or mirrorless camera and are ready to get serious about wide-field astrophotography.
• Excellent for astro-camera users, provided you dial in your adapter spacing and calibration.
• Less ideal if you need autofocus, weather sealing, or prefer ultra-wide or ultra-long focal lengths.

In short, this lens is like an honest, hard-working friend — it doesn’t boast, but it consistently delivers. It’s built for those who value results over bells and whistles.

What about you? Have you used the Samyang 135mm f/2 in your setup? What camera have you paired it with — and what celestial wonders have you captured? I’d love to hear your experiences in the comments below.

Until next time — clear skies, steady mounts, and may your focus always hit infinity.

— Steve

If you are seeking a more detailed review of the lens then try this one  - I take no responsibility for the website or any links from it - but I did find it an informative review - https://stellardiscovery.com/samyang-135mm-f-2-widefield-astrophotography/