To give practical examples to those who want to get into this kind of photos, I decided to leave the base, a shot wide field of the milky way, aiming at its zenith, which is above our heads.
First we talk about the equipment you need, well, I want to emphasize that a first experiment and try to photograph in the milky way, which is a single shot or multiple shots the only equipment really necessary is only a tripod and a camera with wide-angle lens, as well as a good dark sky for shutter speeds of no more than 20/25 seconds, it stars ovals.
To check and find a dark location you can use internet, that’s a good map using google : http://www.blue-marble.de/nightlights/2012
One or more shots, definitely more than one possibly, I propose the differences of one single shot, to give you an idea:
We have a better result already combining via software 3 shots, as you can see in this example:
While lining up at least ten shots, in this case 30, and despite all the limitations of the case (*), the result is clear and still fascinating and I would propose the following image, Valentina was taken using a common mirrorless camera Canon EOS unmodified M (*) on a tripod and shots 25 seconds to 10 mm fixed focal length for a total of 15 minutes of shooting :
The limit in relation to a celestial motion tracking is performed with astrofoto the detail of the sky, the milky way is weaker because of the short exposure times and some colors are less because of the presence of IR/UV filter for Canon camera factory.
These are two examples of astrophotography with longer and snap and total integration and using a dslr camera modified to receive the infrared, how do you see the range of colors is greater:
The second of these images presented is the one that gave me the inspiration to achieve processing Tutorial and guidance that will analyze the necessary equipment and will explain how to use it.
But FIRST, you need to:
- choose the right night – There’s little point in heading out to photo the night sky if it’s cloudy, so find and check a decent weather forecast beforehand. If it’s particularly the stars and milky way you’re after, choose a night with a small or ideally new moon. There are many lunar cycle phone apps that can be downloaded for free.
- choose a dark location – Obviously you’re looking for somewhere with some good scenic possibilities, however ideally this needs to be as far away as possible from any obvious light pollution.
Let me start by saying that wanting to stay on a minimum budget, with a modest sum, say from 100 to 600 euros you can gear up for the wide field Astrophotography with DSLR cameras; the figure varies depending on how much we can recycle the equipment for photography, our handedness and compromise due to invest too much money in a passion that we don’t know how we will have.
Here’s what we need specifically and point by point:
- a DSLR camera, better Canon solely for a budget speech, if we want to be around that figure, and the recommended models are: the EOS 450 d until the most recent (why use liveview is very handy, but also a 350D which is lacking, can fit, with more effort in fuocheggiare).
My advice is to spend initially one body for this kind of shooting (and which can be expanded to daytime infrared photography), because now a DSLR body used like a PowerShot can cost 150 euros, a relatively very low, and for the same amount among amateur astronomers you can buy it already modified for astronomy , saving further. Of course most recently the camera more the price goes up
- editing/blocking on a DSLR camera that needs at least the lowpass filter removal LPS1, this can be done with your own hands if you have particular skill and dexterity in doing these things (See: http://stefanofocosi.altervista.org/ModificaCanon.html) or from shops/Labs in astronomy and photography, scattered throughout Italy and in the world (As in Northern Italy : https://www.telescopi-artesky.it/132-changes-reflex). We do not recommend most expensive changes or filter replacement lps with another glass that filters a lower band ir/uv, or simply transparent to retain functionality of auto-focus calibration that otherwise is not. This is because it is significantly more expensive and to start is not required, but also because in some makes and models of these filters are arising about the stars, flare problems of unwanted and unpleasant, so tricks:) to save about 100 euros to do make the change
- a tripod sturdy enough, headless, usually simply unscrew it and screw head protruding. If you have one we estimate a 80 euro for a good tripod not too heavy with a maximum load of at least 4 kg
- One Star-tracker, which is that device portable enough, fits easily into a small backpack/purse that allows you to track the Earth’s motion with the camera and autonomy of all night, are sufficient 2 max 4 AA batteries according to the model. Can hold several minutes exposure without the stars from being moved or used as a goal, depending on the focal ovalised commonly can hold no more than 3 minutes for single exposure, focal length lens than to 180/200 mm. Price per one startracker that can withstand up to 100 mm for 2/3 minutes focal will be about 400 euros, 200 euros for an used and between the various models of startracker that are now on the market you are spoilt for choice, we can recommend a Ioptron skytracker, or a Skywatcher StarAdventurer, the first more compact, the second that can accommodate and sustain even two cameras simultaneously.
- a timer/remote programmable intervalometer on ebay/amazon if they are 20 euros, but if you want to venture into the Magic Lantern firmware hack is compatible only for some canon cameras, the latest release is integrated the intervalometer and the Bulb setting in the menu of the camera for which you can also save 20 euros:) Soon I will publish a blog post to explain Magic Lantern and other methods for most geeks
- Head-torch with Red light and Warm clothing and of course, lot of time!
Finally we need to set the camera lens to manual focus, obviously the quality and bright as possible to start just fine between 10 and 50 mm focal length, and aperture is not beyond f/4.5 possibly. One example is fine for a first test the classic 18-55 zoom lenses but if not excellent and expensive Bill should be avoided in astrophotography, preferring a fixed focal length.
To give an idea of how it should look and be configured your setup Astrophoto shooting wide field the following are two images both with the ioptron than with the skywatcher:
And here is a link to a site of equipment used for astronomy enthusiasts: http://www.astrosell.it
Found all the equipment, charge the batteries, and loaded our car, what we need to do, besides go with all our equipment in a location the darkest possible is to place all your gear, put in bubble the tripod making sure turn to the North Star and then point it, without moving the tripod, telescope included in the star-tracker.
How to find the North Star? You just have to know at least the constellation Ursa Major, Polaris is part of Ursa Minor, and then viewing the Big Dipper, the two stars of the cart off the rudder should be prolonged is dropping a line, after three lengths, which are calculated on distance of these two stars in Ursa Major, we will select the Polar Star, the brighter that area and representing the extreme small rudder star in Ursa minor.
This photo may be of assistance:
Found the pole star in the field of our telescope, we didn’t finish the alignment because Polaris isn’t exactly matches the Earth’s polar axis, so I’ll explain the simplest method or use a simple APP on your smartphone, there are several, but I suggest that free Iphone, produced by the same ioptron available at this link: https://itunes.apple.com/it/app/ioptron-polar-scope/id564078961? mt = 8
Or the one for Android, I’ve found, but this link works fine and costs nothing: https://play.google.com/store/apps/details?id=com.techhead.polarfinder&hl=it
Then we perform the fixes on our star tracker telescope, as indicated by the app on your smartphone and if we performed all the operations correctly keeping the telescope horizontally, we can move on to making your focus, very important!
For docusing you can just open the lens to infinity focus, also increase the iso to at least 1600 iso, always being careful to strike the tripod losing is level and does not change the polar alignment and aim a bright star in the sky; When will once visible in the optical viewfinder and we approached the correct focus, with the digital zoom, liewview 5 x or 10 x you can finely adjust the focus, then we can start with our shots!
Don’t miss to think about how compose the photo – Before heading out into the dark it is important to have a good idea of what you’re going to photo. Ideally if you have the time and the patience it’s worthwhile composing the shot before full dark. However be prepared to improvise a bit depending on the location of the stars / moon (more on this later).
Now we can move on to reading the next Post with the Video-Tutorial to process the shots: