About Me

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A retired Welshman living in wonderful Plymouth in SW England, I’m a family man, novice sailor and boat builder, astrophotographer and motorhomer. With a passion for all things to do with education and the sea and skies above, I have a sense of adventure and innate curiosity. I write three blogs. ‘Arwen’s Meanderings’ charts my learning to sail a self-built John Welsford designed ‘Navigator’ yawl. Look out for her accompanying YouTube channel www.YouTube.com/c/plymouthwelshboy . ‘UnderSouthWestSkies’ follows my learning journey as I take up astronomy and astrophotography; a blog for beginner’s new to these hobbies, just like me. ‘Wherenexthun’, a co-written blog with my wife Maggie, shares how we ‘newbies’ get to grips with owning ‘Bryony’ an ‘Autosleeper’s Broadway EB’ motorhome, and explores our adventures traveling the UK and other parts of Europe. Come participate in one or more of our blogs. Drop us a comment, pass on a tip, share a photo. I look forward to meeting you. Take care now and have fun. Steve (and Maggie)

Sunday, 16 March 2025

Discussion equipment - Why continue to use a DSLR camera instead of a dedicated CMOS one?

 Why use a DSLR camera instead of a CMOS one?

Do you believe in co-incidence?

On Friday night, I had a discussion with another astrophotographer during a break in our Astronomy society monthly meeting.

Topic? “Why use a DSLR when CMOS cameras are easier?”

I was admiring his rig – Redcat 51, EAF focuser, ASIair plus, some CMOS camera I can’t remember the designation of, a 32mm guide scope with ASIair 120mm mini camera; all on some HeQ mount that again I’ve forgotten. His suggestion? Improve my rig by getting a CMOS camera to attach to my zenith star or Samyang 135mm.

Where is the co-incidence bit?

This morning on my Facebook feed up pops a discussion topic in one of the astrophotography forum groups I subscribe to….. wait for it……… ”Why do people continue to use DSLR’s when CMOS cameras are better and easier to use?”

Co-incidence – powerful stuff!

I’d already been thinking about my answer to this question before the Facebook feed emerged. So, here is my personal perspective. I use a DSLR because:

1.       I already had it and am familiar with its settings, capabilities, and limitations

2.       I had and have subsequently purchased a variety of lenses to use with it

3.       I can use it for milky way landscape astrophotography

4.       And use it for daytime photography as well

5.       I could spend what limited funds I had on other bits of equipment needed for my rig

6.       My DSLR already has a CMOS sensor

7.       Dedicated CMOS cameras are expensive and I get easily confused as to what one I should get for my rig (not really a valid reason as all I need to do is some basic sensible research)

8.       I think, but don’t really know this to be true – that my DSLR is better for wide field astrophotography, aurora pictures, star trails and comets?

9.       I get an instant image on the back of my LED screen – very gratifying as a beginner to astrophotography

10.   I don’t need to link it to a tablet or computer when out in the field

11.   I am learning the how’s and why’s of astronomy/astrophotography with it – walking the walk, learning the craft, doing the basic skills development

12.   It has minimal additional software requirements

13.   I got it astro-modded!

 

That seems plenty to be going on with. I am sure there is a longer list of why I SHOULD switch over to a dedicated camera but, hey, I’m welded for now, to my trusty, faithful Canon DSLR. I love it.

Oh yes! The astronomy society meeting was excellent. The second one I have attended in Plymouth. members arrived with various pieces of equipment. Good to see and hear peoples experiences with the Seestar 50 and the dwarf Seestar 30. Impressive pieces of kit but, for me, taking away the 'learning' that comes with using traditional telescopes and astrophotography rigs. 

So much knowledge, kindness, willingness to share and learn with each other. Fantastic society. I have decided to pay the full subscription at the next meeting. 


Thursday, 13 March 2025

Imaging session - Trying to learn the techniques of blending two images to form a composite in affinity photo

 Newly arrived to my blog? Want to know more about me before you dive into my posts? Why not visit the home page first and start your exploration from there: 

https://undersouthwestskies.blogspot.com/2025/01/welcome-to-my-new-astronomyastrophotogr.html

And welcome. Welcome to 'UnderSouthWest Skies'. Thanks for stopping by. I hope you find the experience worthwhile. This blog post has been written from my own 'beginner perspective' after doing lots of reading on the topic below.  In getting my head around it all, I may have got odd bits slightly wrong; but, like you, I am on a leaning journey, so please forgive any unintentional errors.  Meanwhile, clear skies to you. Take care and thanks for visiting   Steve aka PlymouthAstroBoy 


Now here is the thing. 

I can capture astrophotography data on the night. I'm getting better at working out the exposure triangle settings and checking my histogram on the night. Likewise with using my tracker and gaining sets of lights, flats, darks and bias frames. 

Beginning to understand taking landscape shots in blue and twilight hours. Lousy on landscape composition of foreground however. Loads to sort out there. 

My real difficulties though, and please don't ask me "why?" because I don't know, is understanding how to merge two images into one in affinity photo. You know - putting a foreground with a sky shot. It seems so easy on the YouTube tutorials and yet whenever I try - a disaster. 

Anyway, here is my first efforts. And yes, I know the sky is completely wrong proportion etc - but its just a practice image - trying to learn how to replace a sky in a shot; how to select an object from another image and place it into another.

I really find selections, masking and layers control really difficult to assimilate and I just don't understand why! 



Which of the two images is the least worse? got any tips on how I can improve them? Drop me a comment below - all help appreciated - especially if you are an affinity photo user. 



Sunday, 9 March 2025

Checklist - An equipment check list for a milky way astrophotography session

 As I get older, I get more absent minded and forgetful. I've lost the car a few times in various car parks. I've left the phone on the car roof and lost it! I once left my GoPro camera recording a night session and had to drive back and get it. Fortunately it was still dark, deserted and the GoPro was attached to a fence post and not immediately noticeable.

My real pet hates are when I forget to pack something I need. Last time I left the powertank behind and had to drive twenty minutes home to get it - having assembled the rig earlier only to discover that...... you get the picture. 

I've done something similar with the tripod as well! 

So, I use check lists. There are a few posts here showing my various checklists. It is a system which seems to have helped me enormously when I was dinghy cruising and expeditioning. 

So, without further ado, here is my milky way night session check list. Hope you find it useful. If I have missed off anything, drop me a comment below and I will add it in for all. 

Clear skies, take care, stay safe and have fun out there 

Steve 

 


And just in case you cant get the picture printed off - here it is in text below 

SWSA 2i gear

 

 

Text Box: Copyright: PlymouthAstroBoy
www.UnderSouthWestSkies.blogspot.comGeneral equipment  - safety

Tracker and base

 

 

Headtorch+ spare

WO base wedge+plastic shims

 

 

Penknife

Counterweight assembly+bar+one weight

 

 

Garmin InReach PLB

AA batteries

 

 

Charged smartphone

Large flat dovetail clamp

 

 

First Aid kit

Round dovetail clamp

 

 

Space blankets + Bivvy bags

MSM Z base

 

 

Hand warmers

Gorillapod joby ball head

 

 

Compass + Map

Polar scope illuminator

 

 

Driving and reading glasses

Camera connect cable

 

 

Insect spray

Green base plate

 

 

Fleece blanket

Right angled polar scope viewer

 

 

2 emergency red glow sticks

Kneeling mat

 

 

(Small bothy) (small beach shelter)

Benbo CF tripod

 

 

Clothing

Green laser adapter+pen

 

 

Waterproof

Camera Gear

 

 

Duvet coat

Canon 800D+dummy battery

 

 

Thermals

Lenses – Samyang 14mm, Canon 22mm+50mm

 

 

Hats and gloves – fingerless and over-gloves

GoPro Hero 9+batteries + tips book

 

 

Beanie/buff

Canon batteries -spares

 

 

Walking boots and thick socks

Cleaning kit + small tripod screw adapter thread

 

 

 

Whit flats ring + Bahtinov masks

 

 

 

Intervalometer + AAA batteries

 

 

Other

L bracket

 

 

Hot drinks/hot water

Dew band

 

 

Teabags/food/snacks

Small Joby Gorillapod tripod

 

 

(Trangia, fuel, matches)

Optolong L Pro + other filters

 

 

(Lightweight camping chair)

Spare memory cards

 

 

(camping mat, lightweight tent, sleeping bag)

Log/note book  + Pen

 

 

Reading book

Small handheld diffuse glow lamp

 

 

 

Samsung tablet for flats

 

 

 

Power

 

 

 

3 x power banks

 

 

Velcro cable ties - spares

Usb cables – C, micro and A

 

 

Small roll electrical and/or duct tape

Spare C2032/2025 disc batteries

 

 

Small masking tape strips card

Spare AA and AAA batteries

 

 

Small screwdriver/hex key tool kit

 

 

 

 

 

 

 

Car keys , wallet

 

 

 

Left emergency plan – location, routes, times

 

 

 

 


Saturday, 8 March 2025

Equipment - Making a DIY right angled viewfinder for a star tracker polar scope

Newly arrived to my blog? Want to know more about me before you dive into my posts? Why not visit the home page first and start your exploration from there: 

https://undersouthwestskies.blogspot.com/2025/01/welcome-to-my-new-astronomyastrophotogr.html

And welcome. Welcome to 'UnderSouthWest Skies'. Thanks for stopping by. I hope you find the experience worthwhile. This blog post has been written from my own 'beginner perspective' after doing lots of reading on the topic below.  In getting my head around it all, I may have got odd bits slightly wrong; but, like you, I am on a leaning journey, so please forgive any unintentional errors.  Meanwhile, clear skies to you. Take care and thanks for visiting   Steve aka PlymouthAstroBoy 


Finally, I have got around to making a right angled polar scope viewfinder. The cost of them is around £80 mark with postage, here in the UK. I had an old pentax DSLR right angled view finder and I was sure I could 'adapt' it. Now there is an issue in that this old one mirror flips everything horizontally....but more of that little quirk later in the post. 

I've wanted one of these right angled viewers for quite some time. I find it increasingly difficult to bend down and look up through the central polar scope of my skywatcher star adventurer tracker (same for my Ioptron sky tracker as well).  There isn't an astrophotographer alive who uses a star tracker who doesn't understand this issue. Here at a latitude of 50N - the tilt of the tracker is such that when the polar scope is inserted, you are on your knees with your back arched to look up through it. If you can do that! When I'm on my knees below it, my eye is around 14" away from the viewfinder - rendering it useless! If I try to get underneath it and closer, I invariably end up knocking the tripod and then struggling to get back off my knees - very frustrating! 

When doing DSO astrophotography and using my ASIair mini - then there is no problem if I am slightly out in the initial polar alignment as the ASIair helps me correct it quickly. But when doing milky way astrophotography - then a right angled viewing gizmo is going to be very helpful indeed. 

So what stuff did I use?

  • an old pentax right angled DSLR viewer
  • electrical tape
  • an old polar scope cover piece I had knocking about
  • some very tiny phillips screws 
(I should at this point just explain for those not in the know, that a polar scope is essential to getting good alignment with the stars so that the camera tracks their movement above and trailing stars is avoided. This involves aligning the tracker with the north star Polaris. The bigger the lens you use, the more accurate you have to be in your alignment processes - otherwise you will have horrible trailing and photos that cannot be stacked together in any available software.)


I removed the metal silver viewfinder frame off my ebay purchase by undoing the four tiny screws and then took the protective cover lid off the polar scope. Using the silver viewfinder slot as a template I then marked out drill holes and also a central large hole to be cut out.



Ten minutes judicious use of my multi-tool with drill and then sander bits and hey presto - the protective lid had been cut out. It was then just a matter of screwing the lid back onto the DSLR viewfinder and then doing a few trial fits. 



It proved to be a little loose but a thin strip of duct tape on half of the lid lip - turned it to a fairly snug push-on fit. 

Does it work?  OF COURSE IT DOES! 😁
I have genuinely surprised myself - no more wet knees, cricked neck or wrecked back muscles. 


And it works on the star adventurer too.

So what about the flipping issue? 

Ok, how best to describe this? For some reason, the right angled viewer mirror flips the view of the polar scope reticules. So, 3 o'clock is at the 9 o'clock position and obviously, 9 o'clock switches over to the 3 o'clock position.

What does this mean in reality? Well when positioning Polaris on the correct place in the inner circle of the reticule using a polar alignment app to help determine its position - if Polaris is shown at the 5 o'clock position on the app, on my reticule, when using the polar scope, it will have to be placed at the 7 o'clock position instead.  It takes a minute or two to get your head around it - think mirror flip of the reticule along the vertical axis. 

It may sound confusing but in reality is quick and simple to work out; as long as I remember!! 

I spent around £2 in all instead of £80 so I am happy and I have reused/recycled something to boot. 

With plastic 3D printers etc - I am sure there is a free template for making the bit which fixes a viewfinder to the polar scope on the tracker. 

I found this Sky at night article which gives a better overview on how to do it than I have above