Shooting for the Stars. An Astrophotography Primer

I thought I’d stay on the photography theme a little while longer and touch on a subject I have been playing with off and on for a while now, and that is astrophotography.

I first approached this at the beginning of the millennium when I still lived on the Northern Beaches of Sydney. I had interviewed someone who as it turned out lived close by and was somewhat famous in this area of photography and videography, Steve Massey.

It Started With a Telescope

This got me all fired up and so I went out and spent serious money on a telescope and a film based Minolta SLR camera, and spent many happy hours shooting images and video of the Moon primarily.

When I moved back to Western Australia and down to the deep forests of the south-west of Western Australia, I upgraded the telescope and also abandoned the Minolta in favour of a Canon 5DS dSLR.

The absolute lack of ambient (and therefore interfering) light was offset by the amount of cloud we used to get, so the actual telescope time was minimal. And then a particularly ridiculous accident I want go into knocked the telescope and its tripod over rendering the focussing mechanism impossible to use.

Shortly after I moved back to civilisation 200Km south of Perth, and with COVID hitting decided to try and revive my damaged telescope.

The spare parts were available, but all things being what they were it took nearly 9 months to actually get them here!

In the interim, I discovered a little gizmo called the MSM, or “Move-Shoot-Move”.

And its brilliant.

Science

A little bit of science is needed here to fully explain what the MSM does and why.

When you first get a telescope, you suddenly became Aacutely aware that the Earth moves through space, and pretty damn quickly at that. It first struck home when I finally managed to get an image of the Moon in the ‘scope that was nice and sharp. I had to go inside for something another – only gone a minute or two – and when I came back out, my image had gone!

Of course, the Earth is ripping through space at something like 500 metres per second or around 1600Km / hour at the equator. Hence the image of the Moon is moving across the field of view of the telescope at the same rate, so you get about a minute depending on the magnification of the telescope.

If you are lucky enough to be able to get, say Jupiter or Saturn in sight AND focus, then you have mere seconds.

But to get decent still shots, which require lots of light, you need more than this, so there is the dilemma.

You can buy mechanisms for telescopes to follow the earth’s rotation and also lock in on celestial objects, but this tends to get very expensive for the hobbyist

So, enter the Move-Shoot-Move (MSM).

MSM

msm-polar-aligned-side-v1-2The MSM is a small black box that mounts onto a tripod. There, that was easy.

But there is a lot more to it than that of course. You see, once it is charged up, and via various mounts, a camera attached – either DSLR or Mirrorless – the inbuilt motor rotates so that when you have locked onto a subject in the night sky, it will always stay in place as the camera rotates with the Earth.

You set the camera using either its inbuilt intervalometer or an add on one and set the aperture and ISO accordingly. If all goes well, you get shots like these.

Inter-what?

An intervalometer is either an inbuilt function of the camera – and many have it – to tell the shutter to stay open for a specific period of time, beyond the normal 1/500th or 1/20th sec for example. To get shots like shown here, shutter times of up to 10 minutes or more are used.

The smart ones can also be set for multiple shots that are timed and other functions.

2022-12-14_16-26-48If your camera does not possess an internal intervalometer, go to your favourite camera store and ask for an external one that suits your make / model. An example of one I can recommend is the Hahnel Captur Timer Kit from  Leederville Cameras.

And while you can fluke it and get a great shot with a single image, those that are REALLY good at this stuff take many, many images of the subject in order to get as much data as possible, and then using specialist software, much of it free, “stack” these together to create a single composite image.

Polar South

Of course, there is a catch, sort of. You’ll recall when I stated the Earth’s movement rate, I was careful to clarify that this speed is “at the equator”. The Earth rotates at different rates depending on where you are, and so the MSM needs to be calibrated in order to get the exact setting.

In the Northern hemisphere this is relatively easy as they have a celestial body in the sky (where else I suppose?) called the Pole Star which to all intents and purposes is based exactly at True North. By calibrating the MSM, using a laser scope that comes with the system, to the Pole Star, you are good to go.

In the Southern Hemisphere we don’t have that luxury, and while there are ways to do this with methods using other stars, these are relatively complicated. So, there is a far better way, and it has added bonuses too.

PhotoPills

2022-12-14_16-24-14I have mentioned the PhotoPills app before in stories, in order to calculate sun and moon rise times and locations in order to get the right positioning and timing to get specific shots.

But another piece of magic PhotoPills does is let you align the MSM quickly and easily to correctly set it for shooting deep space shots and stars. A combination of the inbuilt compass and a virtual reality overlay, with your smartphone attached via a mount to your MSM, lets you align perfectly to Polar South by simply lining up cross hairs to a central target.

With that done, you can then mount your camera, adjust the appropriate settings for aperture, ISO and the intervalometer and you are good to go.

In theory.

Final Tips

2022-12-15_15-21-30Of course, to get the perfect shot takes lots of practice and patience. I’d recommend a few things to make life easier.

  1. Initially don’t be too ambitious. Just get some shots to get a feel for what you are doing and learn what settings may be best. And make notes, or better, shoot RAW so the camera settings are embedded into the meta of each image
  2. To learn where planets, stars, constellations, asteroids, meteor showers and other stuff up there are, download a copy of the free program Stellarium for your PC, Mac, tablet whatever. It is absolutely bulging with information and can also create virtual skies based on locations and times.
  3. Get yourself a headband light that has the red-light option. This way, you’ll be able to see what you are doing but not stuff up your night sight.
  4. Use a decent tripod. The one thing you do not want to happen is for your camera to move in any way at all. I use a Miller Solo75 and can highly recommend it.
  5. The MSM is rated to a specific weight so this limits the lens you can use. Even my Canon 5DS with an 80-200mm is too heavy, so these days I use a Fujifilm X-T20 with a 16mm f/2.8 which is pretty close to what it appears the experts in the field use. But even if you have a base camera with a 28mm or something similar, you can still get some breathtaking shots.
  6. Apart from no camera movement (apart from that given by the MSM of course) the other thing that is imperative is focus. You must have your subject in absolutely pinpoint focus. Some cameras allow you to zoom into the image on the LCD for focussing, so if you have this use it. Otherwise focus to infinity but pull it back just a fraction. Some people place a piece of tape to lock the lens in place once they have that sweet spot worked out.
  7. Learn your camera. Shooting stars and planets etc is NOT the place for “A” for “Automatic!”
  8. Keep away from as much external light splatter as you can. The darker you can get it the better. Avoid streetlights, light from windows, car headlights and even the light of the Moon as much as possible.
  9. Look at as many YouTube tutorials, read as many online articles and so on as you can. There is always something to learn. There are some great tutorials on the MSM web site as a starting point, and you’ll also find some really good YouTube channels you’ll like. I started with this one.
  10. Above all be patient. Hopefully you’ll jag a great shot within your second or third attempts, but if you haven’t, just keep trying as when you do, it’s worth the wait and effort trust me!

Review: Canon EOS RP (with an MSM Star Tracker)

It seems like forever since I did a proper camera review, but here we are. In the past I have mainly concentrated on camcorders and video cameras and so-called “action cams” or looked more at the video capabilities of mirrorless and 4/3rds models, but over the “COVID Break” and due to popular request (and responses from surveys), I have decided to branch out and look at cameras such as the Canon RP we have here.

But rather than just as a still camera, in this case (and another camera I’ll be reviewing very soon), I am putting it through its paces in special circumstances; using it with a wide and fast lens to capture images of deep space.

The Camera

Let’s look at the physical aspects of the camera first.

The Canon EOS RP is a lightweight (440g body only), full frame mirrorless unit that shoots up to 26 megapixels. It supports 4K video and natively has a RF lens mount.

In my case, I requested and got and EF-EOSR mount adaptor in order to run the 16mm – 35mm f/2.8 lens I wanted for the star shoots.

On the rear is a swing out, rotating 3 inch monitor with 1.04 million dots, and this is supplemented by a 0.39 inch EVF with 2.36 million dots.

The RP sports a combination stabilisation system and the auto focussing has over 4500 possible positions. Wi-fi and Bluetooth are both supported.

The ergonomic layout is pretty much Canon standard with a rotary dial on the left along with the shutter release, lock, movie shoot button, main dial thumb wheel, mode wheel, and multi-function button. On the left is the on/off switch next to the hot shoe.

The rear of the body has a menu button at top left, and the right hand side an AF and AE lock button, a multi-purpose magnify/ reduce/ AF point button, info button and a navigation button / arrow combination. Beneath that are playback and delete buttons.

Access to the battery is via the bottom of the body of the Canon EOS RP and this also holds the single SD card slot.

On the left-hand side underneath rubberised flaps are a 3.5mm mic port, a remote terminal plus mini HDMI and USB ports.

As I said, pretty much standard fare.

By the way, for the star shooting, a remote terminal and controller is almost mandatory due to the long shutter times used.

The lens I am using is, as mentioned, a 15-35mm f/28 USM which required an EF to EOSR mount adaptor. Once this was installed and the lens attached to the camera, all that was needed was to attach it to the MSM mount setup on my Manfrotto tripod.

MSM Mount

I have had the MSM mount kit for a few weeks now and still coming to grips with the best way to set it up as there are a number of possibnilities. The major problem is we are in the Southern Hemisphere, and the mount has to be calibrated to a pole star to work properly ie: to follow the rotation of the Earth at the correct speed and inclination.

In the Northern Hemisphere they have the Pole Star, but here we don’t have such a thing. This is where the PhotoPills app comes in. This shows a “virtual” sky on your smartphone or tablet letting you align the camera to the south pole. This then allows the mount to track successfully and stop getting any star trails (unless that’s what you want of course).

The second part of the problem is that due to our location and the direction of the rotation of the Earth, the mount and camera can have a nasty habit of unscrewing themselves over time. Subsequently, whilst in the Northern Hemisphere taking long duration shots over a 10 or more hour period is not unheard of, I have no intention of trying that here and having a loan EOS RP end up on the ground (or my Canon 5DS for that matter!)

So I am waiting for a clear night when I can get a series of 1 minute shots – about 30 of them, maybe more – I can stack and then with the magic of the stacking software, Deep Sky Stacker to start with, hopefully get images similar to this.

The MSM mount itself is made up of a series of components as you can see. The main rotator has two points where it can be mounted. One on the large side (which I am using here) but it can also be tipped at 90 degrees.

This is sitting on a Wedge mount attached to the tripod letting you change the inclination of the camera when attached.

On top of the MSM rotator is a ball mount and the camera is attached to this.

On the rear is a bracket to mount a smartphone so you can use the PhotoPills app in situ to set the orientation to the south pole correctly. You also get in the MSM kit a green laser, but here that is pretty useless for the reasons mentioned. In the Northern Hemisphere you would use this to align to the Pole Star.

DCIM100GOPROGOPR0455.JPG

Due to the nature of the MSM Rotator and its accessories, there are a number of ways you can mount your gear. Some people use an optional Z mount as against the wedge, but after much chopping and changing over the weeks, this method seems to be the best for what I want.

The Canon EOS RP and 16-35mm lens sit perfectly and are well balanced for the task at hand. Now we wait for some clear night(s).

Thankfully here in the West (I am 200km south of Perth) we have mainly had these so I am hopeful over the next 24 – 36 hours we can put the Canon EOS RP to work.

Stay tuned!

 

 

New Month and new things to snap / video

If like me you have become a fan of looking up at the Moon, planets, stars, galaxies and all that other stuff up there, the month of March gives a wonderful opportunity to discover and get imagery.

For example, according to PhotoPills (read on if you don;t what PhotoPills is) in March, The Zodiacal Light, the Milky Way and Galactic Centre, Venus at greatest eastern elongation, the Full Moon, the conjunction of Venus and Mars, the March equinox, the conjunction of the Moon and Mercury, Mars, Venus, Jupiter and Saturn, the Messier Marathon, Sunrises, Sunsets, Star Trails and more will be available to shoot.

Here is some more info:

Two invaluable things you need to get the best, especially for the beginner (of which I classifiy mysself one) are a pair of apps designed specifically for these purposes.

PhotoPills I reviewed a few weeks back, and for working out what to photo / video and when, assist in setting up equipment and a zillion other reasons is definately a must. It is available for both Android and iOS and if you missed it first time around, here is a video explaining PhotoPills far better than I can in words.

To get Photopills, go to the App Store or Play Store, or mouse over to https://www.photopills.com/ for more info

The second app, and one I have been using for some years is Stellarium and this is truly an amazing piece of software. Even more amazing is that is free.

To digress a little, my favourite set of books is “The Foundation Series” by Isaac Asimov, and in there Asimov describes what he called “The Galactic Lens”, a 3D view of the known galaxy available from any point. At the time of writing, to acheive such a thing was mind boggling and probably beyond the comprehension of anyone to actually implement due to the massive processing power and memory needed by the scales of the time. Remember back then, what few “computers” they had were all driven by valves, not chips (Look up “vacuum valve” kiddies on that new fangled Goggle search thingy) and memory was measured in bytes not gigabytes or terabytes. Hard to fathom I know, but its true.

In essence, Stellarium is the Galactic Lens, but not just giving a view of the galaxy(ies), also housing a complete database on every object known in the sky above (see the screen shot above. In this one, one of Elon Musk’s Starlink satellites has been selected, but you could click on any star, planet, meteorite, comet, moon etc and get the relevent information).

With Stellarium you set a home point and immediatelyy have access to the night (or day) sky in real time. There are heaps of features available and I am still learning. To get it, and its available for Windows, MacOS and LINUX, and in a mobile form for iOS and Android, go to www.stellarium.org.

If you have been put off thinking getting those fantastic star trails, images of deep space objects or even sharp photos or videos Saturn, Mars, Jupiter etc is all too hard, think again. Better still, give it a crack. You do NOT need fancy expensive equipment!