Images representing different hobbies

Astrophotography

You are never too old to learn, and one of the thing that has opened my eyes  has been discovering the quality of astronomical images that can be produced by amateurs with very modest equipment. By using digital cameras and image processing software it's a realistic ambition to produce images that compare favourably with those produced by the world's biggest telescopes fifty years ago - right in your back yard!

This website does not showcase the best astronomical pictures on the internet! It's a selection of pictures I have taken myself with basic equipment and free software. Producing images like these below, or even better ones, is within your reach!

Most importantly, you don't have to spend a fortune. My scope, mount and tripod coast £180 on Ebay. I spent £40 on a more solid tripod, and about £200 on various bits and pieces including books and an ancient Canon EOS DSLR and a seconhand Microsoft HD Webcam. The results shown before are  some of my best so far, and will be updated from time to time.

Perhaps the easiest target in the sky is the moon. You can get good pictures with any long or zoom lens, this is a 'stack' of six pictures taken with an ordinary bridge camera:

A Gibbous Moon photographed over thr Isle of Skye in near-poerfect seeing conditions

A gibbous moon photographed on the isle of Skye.

Follow the links below for introductions to some of the other things you can image in the night sky:

The Moon

The Sun

The Planets

Messier Objects

Star Clusters

Nebulae

Galaxies

Constellations

Meteors

Have a go!

I hope I have convinced you to have a go at photographing the night sky - these photos may not hold a candle to some of the work of professionals like Damian Peach or even dedicated amateurs, but I hope you are surprised what can be done with kit that has cost me well under £500.

There are lots of places to find out more on line, but perhaps the easiest place to start is the StargazersLounge webiste.

As well as the subjects covered above there are all sorts of other things to look out for - comets, asteroids, meteors, aurorae, noctilucent clouds and various metereological effects such as sundogs and lunar halos. And sometimes there are just picturesque events such as this near conjunction of the Moon and Venus.

Conjunction of Moon and Venus seen ona slightly misty night, with teh moon partly behind trees

A Conjunction of Moon and Venus

 

Tracker Tester is a simple BBC BASIC for Windows utility for testing telescope tracking and guiding setups using a laptop computer.

Simply extract the exe file from the zip folder and save it in a sensible place.

Just click the exe file and it will introduce itself, then change to a black screen and ask you for the screen width in millimetres and the distance of the screen from your scope.

The star will appear as a single white pixel at middle left, just in from the edge. Focus your scope on the 'star'.

When you are ready press a key and the star will move across the screen at approximately sidereal rate as seen from the scope. Depending on screen size and distance it should take half an hour to an hour to cross the screen.

To exit the program, press ALT-F4 (the screen will carry a message to remind you of this).

DOWNLOAD TRACKER TESTER

Tracker tester comes with no warranty of suitability for any purpose whatsoever.

One of the big challenges in astrophotography is achieving really accurate focus, easiest and fastest way of doing this is with a Bahtinov Mask. there are amny ways of making your own masks, but a robust, accurate and convenient solution is 3D printing.

 

3D printed Bahtinov Masks

 

See THIS PAGE for details of how to use a Bahtinov Mask.

Here are STL files to allow you to 3D print your own Bahtinov Mask for some popular sizes of lens and telescope:

Mask.stl for 130mm reflectors with a roughly 150mm/6" tube, such as the Skywatcher 130P and 130P-DS.

Small-Mask.stl for telephoto lenses (catadioptric and conventional) with a 76mm end diameter.

Tiny-Mask.stl for short telephoto lenses such as the Zeiss 135mm F.3.5 'Sonnar' which take a 48mm filter and have an external diameter of about 52mm.

The largest mask requires two M6 nylon screws about 30mm long to be threaded into two holes, these allow it to be 'hooked' onto the end of the scope.

The smaller masks have an 8mm collar which is an easy fit over the end of the lens. if your scope/lens is a slightly different size, scale the X and Y dimensions (but not the Z-dimension) of the nearest-size mask to fit.

Masks can be used directly on a scope or on the end of a dew shield. They are not a close fit, they just 'hang there' so as not to disturb the focus/pointing when you lift them off.

These print best with quite a dense fill (30-40%) and thicker outer layers than normal.They don't need to be black, just opaque.

My masks were printed on a Prusa i3.

Don't forget to remove the mask before taking photos!

 

 

Here's the home of 2017's 'Image of the Month' pictures. Enjoy!

See the 2015 and 2016 images here.

Image of the Month for August 2017: The Bubble Nebula

 

Bubble Ha RGB

This image combines one-shot colour with an astro-modded DSLR from 2016 with narrowband Hydrogen Alpha (Ha) from 2017.

Image of the Month for July 2017: Saturn

 

Saturn 17 June 2017

The challenge this year is that from the UK Saturn is approaching its lowest elevation for the next thirty-two years. Next year it will be slightly lower again, and it will be around 2021 before it rises high enough to make imaging easier.

Image of the Month for June 2017: Jupiter, Io and Europa

Jupiter Io Europa 25 May 17 Winjupos
 
Image taken using a Skywatcher 150PL with a ZWO ASI 120MC camera.

Image of the Month for May 2017: M86 Galaxy and Markarian's Chain

Markarian Chain

 

Image of the Month for April 2017: M51 The Whirlpool Nebula

M51 Whirlpool Nebula

 

Image of the Month for March 2017: The Rosette Nebula

Rosette Nebula

 

Image of the Month for February 2017:The Flaming Star Nebula

The Flaming Star Nebula in glorious Stub-O-Colour

 

Image of the Month for January 2017: The Jellyfish Nebula, a supernova remnant in Gemini.

The Jellyfish Nebula in Gemini

 

Sometimes (perhaps always!) you can go back and take a second look at your images and get more out of them. At the very least it pays to save the stacked but unprocessed data, if not all the RAW images.  In December 2015 I took what I thought were some very beautiful but rather sparse images of M42 and the Running Man nebulas in Orion. the nebulosity was mostly purple in colour.

Since then I have found out about ways of making the fainter parts of a nebula appear in an image, and also got better at balancing colour. This has enabled me to find the browner dust clouds in M42 while still controlling noise. Here's the reprocessed image, with a smaller version of the old one for comparison. Which do you prefer?

orion nebula reprocessed

The 2016 reprocessing of older data for M42 and the Running Man (at top)

orion nebula reprocessed deconvoluted filtered

This is the smoother and purpler original version.

One of the requirements for most astrophotography is a mount that can follow the rotation of the heavens - without this, all your stars will be little (or even long) streaks unless you are using a wide angle camera lens. It obviously follows that your mount needs to be capable of doing this with a reasonable standard of accuracy.

If you visit an astronomy forum and ask for advice on equipment for imaging, you will probably be told that you can just get by with an EQ5 mount or ideally an HEQ5 or EQ6 mount.

Now this is not welcome advice for a beginner as the prices of these mounts are not insignificant, and they often ask if the much cheaper EQ3 mount can be used for imaging instead (there is no EQ4 available). The answer will almost certainly be that the EQ3 is OK for cameras used with relatively short lenses or short exposures on bright objects with light telescopes.

This is NOT true. Most of the people giving this advice have larger, heavier duty telescopes and are used to taking long exposures through narrowband filters. If they have any experience of an EQ3 mount they will remember it as rather smaller and very wobbly.

Now there's the rub ... the EQ3 tripod is very wobbly, but the mount itself is capable of imaging deep space objects very well, at least well enough to keep a beginner happy over their first few seasons. So if you can't afford a more expensive mount or already have an EQ3 tripod all is not lost. You have two cheap options: either stiffen up the EQ3 tripod or replace it with an EQ5 tripod. Stiffening the tripod may set you back a tenner for some M6 studding and wingnuts and an EQ5 tripod will sell for about £50 second hand or around £90-100 new.

Let's look at the cheap solution:

EQ3 Tripod stiffening

 

There you go! It does mean drilling holes in the tripod, but it will make it a vastly more rigid by preventing the bottom parts of the legs flapping about. Naturally you have to make sure you have all the other screws done up securely (not over tightened!) Also, keep the tripod as low as you can, it will be much more rigid, the extension shown in the photos is about right.

If you can get an EQ5 tripod, then the EQ3 mount should drop straight on:

Dual mount on EQ3 Mount and EQ5 tripod

 

All those gears are my home-made RA drive, the thing that makes the scope follow the stars around the sky -you will need to buy one of these if you don't have a goto version of the EQ3 mount. A single axis motor for EQ3 will set you back about £70. I also recommend a polarscope to simplify and speed up polar alignment, about £33 but this is not essential as you can 'drift align'.

Ok, now you are thinking this is up to £200 of extra kit! Why not buy a fully-loaded HEQ5?

Good point - If you are buying new from scratch, get the best mount and tripod you can afford, but if you are skint or like me you start off with a second hand scope that comes with an EQ3-2 mount and tripod attached, this is a way to get started for less.

So, if you already have an EQ3 tripod and mount you only need the studding and motor to get started. If you have an EQ3 pro-synscan goto scope - in which case you just need to stiffen or replace the tripod.

But I've made a bold claim - that the EQ3 mount is up to deep-space astrophotography. Well all the astrophotos on this website to date were taken with my NEQ3 mount (just one flavour of EQ3). The mount has not been modified internally or even disassembled and regreased, all I have done is put teflon grease on the wormwheels and take a reasonable amount of care to get a good balance between backlash and freedom of movement of the RA and DEC adjustments. I should say that 'good balance' is more in favour of free movement than backlash as you can balance the mount 'east side heavy' to eliminate the effects of backlash in RA.

Here's an image of the North America Nebula taken using a 130P-DS reflector with coma corrector on the EQ3 mount. This is a stack of the best 90% of 60 one-minute long exposures:

North America and Pelican

 

Finally, many people will say the EQ3 is only up to imaging using camera lenses as telescopes are too heavy for it. The 150PL reflector weighs about three times as much as the 130P-DS and has over twice the focal length, making it it far more pernickity about the quality of tracking. This image is from the 53 best of 60 one-minute exposures. I'll leave it to you to decide if whether or not you can photograph deep space objects with an EQ3 mount.

M27 Dumbell Nebula