An Introduction to Astro Photography
By On3legs Contributor: Jason LeGuier
Since I was young, I’ve looked up at the stars in wonder. It has always been a fascination of mine. The fact that the objects are SO large and we can see them with the naked eye even though they are astonishingly far away. I’ve wanted to photograph the moon and the planets since forever, and I finally got around to figuring out how. And I’d like to share that with you, in this introduction to astro-photography.
Shooting bright sky objects, is not exactly rocket science (see what I did there?). You’ll need your SLR, a reasonable telescope able to connect and support the SLR, and a connector. It’s almost that easy. Basically speaking, a telescope is a great big lens! You just need to fit it to your camera. And then the fun begins, Finding and focusing… but more about that later. You’ll need to run your camera in manual mode and you’ll need live view on your camera, so pause here if need be and familiarise yourself with those 2 things.
There are many variations of telescopes ranging in price from under $100 to many thousands. I’m going to simplify this in to the 2 main categories: reflecting and refracting.
Being only an interest rather than a hobby, I have a Dobsonian telescope (reflecting) which is a large tube with a mirror at the bottom and the eye piece back near the top. It cost me around $500 including some eye pieces. What this type of telescope is good at, is letting in a lot of light, which is great for photography. The telescope I use has an 8” diameter and in photography language, has a 1200mm focal length. Another great feature of this type of telescope is that it has a 2” eyepiece, perfect for attaching a camera.
Here’s a photo of my Canon 70D attached to the 8” Dob
- A camera connector for your mount (About $30)
- A T-connector to insert in to the telescope eye piece (About $30)
- A Barlow lens to give you extra focus flexibility (About $100 for a decent one)
Whilst you can attach your camera to the tripod with with items 1 and 2, you will likely be extremely frustrated when you can’t see anything. You need to move the camera in and out (using the telescopes manual focus wheel) to move the sensor to the point where the image is in focus.
Normally, an eyepiece will focus the image for you, but you will have removed the eye piece. The Barlow lens allows you to move the camera further back allowing you to focus. I have a 2x Barlow which allows me to focus anywhere from a tree 30m away (well, a leaf on a tree if I’m honest), to deep space objects. The 2 times Barlow also turns your 1,200mm lens in to a 2,400mm lens.
Shoot for the stars, and land on the moon
The first thing you will want to shoot is the moon. It’s bright, it’s easy to find and it’s really cool to photograph!! Take your telescope outside when the moon is about half full. The edges make for very interesting photos. Point the telescope at the moon and set your camera to manual. Turn on LIVE VIEW and set your shutter to about 10 seconds or so and your ISO to 1,600.
We want a nice bright image in the live view LCD in order to try and focus. Now the hunt is on. If you don’t have a tracking telescope (motorised base) you’ll need to slowly move it around until you see the light in your view finder. Once you see that, then you’ll be able to begin focusing in and out until you can sharpen up your image. Be patient. Once you have that, set your shutter back down to around 1/40 or so and take a shot. You should see a reasonable image captured. You can play with the settings from there remembering it’s better to slightly under expose than over expose.
Keep your shutter at 1/40 or greater as the moon moves pretty quickly. You should get some nice pictures.
What else can I shoot?
This will depend on what type of telescope you have. For darker objects, you’ll need longer exposures. The Earth rotates pretty quickly, so a tracking telescope will provide more options. With an inexpensive manual telescope you’ll still get great shots of Jupiter, Mars, Saturn and the moon. You might also pick up 1 or 2 of the star clusters.
Then of course, there are ground based objects. A telescope works equally well during the day, when focused on far away objects. Experiment a little, be creative and you might surprise yourself. Don’t expect razor sharp images at over 2.5m focal length, but it can be great fun.
For around $150, I was able to combine 2 of my life long interests and get some great images. If you have a telescope, and have read this far, get on the web and order your connectors and Barlow lens. If you don’t already have a telescope but are interested in photographing the moon ….. find a friend with a telescope and tell him you want to show him a cool trick. 😉
Jason LeGuier is a talented photography enthusiast specialising mainly in travel and landscape photography. An experienced and frequent traveller, Jason not only produces great quality photos, but does so without a suitcase full of equipment. I am thrilled to have Jason share his experience with you and I am sure you will enjoy reading his posts. Make sure you check out his Facebook Page and hit the LIKE button!