THE CHOICE OF LOCATION:

Choose the place where you do the photo shoot, examine properly its geographical position in relation to your home to calculate displacement and any circumstances delay times. I suggest you read this article to get an idea on how you can organize a photographic excursion. An inspection carried out at least a few times before shooting is always a good idea, both to store permanently the path is to consider alternative routes in the event of an impediment or unexpected in the best way.

IDENTIFY THE OPTIMAL DAYS:

Free time except that it’s not something to be underestimated these days, you have to think according to the weather and the lunar calendar over the internet/tv/newspapers check the weather conditions in the location of so choose the evening/night with predictions of serene, obviously the presence of clouds does not help the good success of one star-trail, you must see the stars!
The Moon is in part an enemy when you want to photograph the stars especially when the lunar calendar tells you there will be “full moon“. The light produced by the Moon hinders this type of photographic work. The sky should be completely dark to get an excellent startrail. Choose if you can do the shooting on days when there is new moon.
Is on the net the Lunar calendars, often provide excellent directions in regard to the location and type of Moon in place on a particular day; This is a good site that shows the present phase and the calendar of the month:

RECENT SECURITY MEASURES:

The night is always unexpected or unpredictable event Theatre, especially if you are moving yourself in areas you don’t know. Don’t forget to get a mobile phone (whose receipt is verified during the project visits undertaken previously on site chosen), and if you really want to be safe keep it with a friend and a comfortable shelter for the night: many fellow photographers do not disdain the use of Canadian or quick Assembly tents in cases where speculate to spend all night out (not wanting to sit in the car) We long we purchased an old camper who became companion cosy, warm and in my opinion more secure than many sessions astrofotografiche.

THE RECOMMENDED EQUIPMENT:

As already described in the Guide to make your first wide field Astrophotography when we were talking about equipment:

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The advice is to buy at the same price-performance (if not already) a Canon body DSLR because it has the characteristics that you need without incurring excessive costs from buying other brands of undoubted more beautifully crafted but undoubtedly more expensive almost approach the cost of a full telescope; especially if you plan to only make startrails, always clarify the ideas before you encounter sostansiose expenses beyond the mere lustful collectibles makes no sense; for the same reasoning as regards the use of focal lengths my advice would be to start to dedicate himself to Astrophotography from focal Court to move to long lenses only secondarily as these more challenging and expensive equipment.

Remember that although it is preferable to have a camera that has the bulb mode in case of purchase, like a lens/wide angle lens as much as possible and bright, it is not essential for a first experience in night shot.
BULB shooting mode, allows you to open the shutter when pressing the shutter button and hold it until a second press of the button. If there is this mode, the camera must allow at least long exposures up to 30 seconds.

Definitely indispensable is a tripod or some other means to hold the camera steady, even still. It also serves the tripod, or whoever, is stable.
Since you take pictures outdoors and that the overall duration of exposure is extremely long, the tripod must remain motionless even if the wind blows.
An extremely useful, but not essential, is a Timer/remote intervalometer wireless wire: most models shown are those that also provide an intervalometer, or at least the option to lock the shutter release. As explained in other posts, on some Canon cameras you can work around it using the firmware hack Magic-Lantern.
Could also use a flashlight, either because you have to take in the deepest darkness, either for a specific creative application, which we’ll see later.

CAMERA SHUTTER SETTINGS:

With regard to exposure, you need to set the ISO to a minimum and use a wide opening. Could be instinctive, if you’ve already practiced landscape photography, think about having to use a narrow opening, then with a large value (such as f/22).
To photograph the wakes of stars, instead, you must use a large aperture because it allows you to capture a greater amount of light.
Since the stars are of very small dots in the sky, not too narrow openings give the time the camera to capture enough light and lead to get pictures that the stars are very weak or even invisible.

However, the depth of field will not suffer under any circumstances, in fact:

• If you use a short focal length, even with very large depth of field is high,
• in any case, the stars are so far away from the focal plane and therefore belong to the same approximately all are all in focus even with wide opening.

The exposure time we talk soon, seen its crucial importance in this area.
To focus, and night is very difficult, but ironically it is easier with a 50 mm rather than a pop-up, or better with a wide, because in the large field even the brightest of the stars may not look.

A trick is to first set a focus toward infinite on target, aim the bright star and then with liveview, once framed, zoom in 10 x and quickly find the focus precisely. Then do not touch the lens ring until after the photo session.

As for white balance, if shots in RAW you don’t worry about it will fix it in post production. If you shoot in JPEG or do you want to save some post-production step, do not use auto white balance.

Choose one of the functions of the camera and run a test shot to see if you like.
You cannot use the custom white balance since the light produced by the stars is not enough.
Finally, many cameras have a built-in noise reduction function. Enable it or not is not an obvious decision.
In fact, in some cases, embedded noise reduction algorithms don’t do a good job. Also, in general the processing procedure is very long, so to equal almost the duration of exposure.
The trick is to break up long exposure in many shorter exposures. You will be so for several photos to be combined using the appropriate software, as we will discuss later in this post.

It remains, however, to decide which exposure time use and how long the various exhibits that will make up the final photo.
For the total exposure time there is no real upper limit although dealing with star-trails, it makes sense to talk about an entire night out best but there is definitely a lower limit.
Being a jerk “abnormal” is a bit difficult to use one of the semiautomatic mode (aperture priority or time). If your camera doesn’t allow this shooting mode trying to use “night scene” or “Fireworks” (especially the “Fireworks” are very similar to the photograph of falling stars).                                                                                     My advice to the star trails is to set M of Manual and set to 30 seconds of exposure, with the intervalometer set to take every 5/10 secs and longer will take longer and will be more clicks, we’ll get our strips of stars.
For this kind of shots it is better to raise the ISO, with due attention to noise that might arise if you’re exaggerating.

In General, keep in mind a rule that can help you figure out what is the maximum ISO over that you should go. Do it this way:

• Your camera arrives at ISO 3200 at most? Then don’t go beyond the 800 – 1600 ISO.
• Your camera arrives at 1600 ISO at most? Then don’t go beyond the 400 – 800 ISO.

In practice, you don’t have to go more than half of its maximum capacity of possible sensitivity.

Composition:

In composing the picture you have to decide first whether you want the wakes of the stars form a circular pattern in the sky or oblique lines (take a look at the examples of photos in this article to get an idea).

In the first case, as the image of this Post, you have to locate the North Star, then North, and point straight toward it. The circular motion of the Earth will do the rest.

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:

In the second case, wanting to regain the Valley and the milky way but also the telescope dedicated to capture on camera, was aimed deliberately southwards, and the intent was to exploit the same shots to mount a time-lapse video (Yes, you can do that, too).

We come to the central element of the composition, which is: what do you want to include in the photo over to heaven?

The majority of photographs with star-trails, it does include some element “terrestrial”, properly chosen. Sometimes this can be a mountain of a building, a tree or even a person.
To give more prominence to the element Earth is also possible, before or after the star trail, bring out the scenery or the Earth element, including a shot at smaller aperture and/or much longer time of exposure, in the order of 2/5 minutes bulb (BULB) or lighting up through a torch light element “earthling”, but it is not essential:) is a finesse and must be evaluated depending on the composition and the subject “terrestrial” in it.

POST PRODUCTION/EDITING:

The last step, since it is still multiple shots and wanting to get a single image that contains them, you must use dell computer.

The procedure to be followed in English is called stacking, which could be translated as “stacking”. It’s about taking all the shots, place them on top of each other and merge them. Combining the movement of the stars, which was originally fragmented into individual images, you will dial without interruption. This procedure can also be done by hand, using software such as Photoshop, importing each photo in a level and merging them with the proper blend mode but this is the slowest method and laborious, as well as onerous, since this is a paid software.

So the solution that we recommend is to use one of a number of freeware software available, but what Fortunately I recommend to use, because we used profitably and is “intuitive” is “StarTrails”

Let us look at the steps to take after the calibration of individual shots and saving numbered consecutively, I refer you to our Post about color calibration for long-exposure images at night:

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Now we must add the Image files from the File menu and proceeding with Open Images as you see in the picture, select them all and proceed by clicking Open.

Uploaded files will get you all are side to side shots of our image

Uploaded files will get you all are side to side shots of our image.

As shown in the picture from the menu Build you can proceed to the composition of our Star-Trail.
We start from Average foreground which allows by combining multiple frames to get a shot of the bottom of the subjects “earthlings” with less noise and more brightness.

The choice of how many frames merge into one Masterframe, depends on the image, from a minimum of 2, in this case there are no terrestrial subjects featured many shots might bring out that we choose a value of 8 only to mitigate the noise present in the raw shots.

Turning now to Build menu option will create the image with the strip called Startrails delle stelle, the software offers us Two merge mode, Lighten and Screenblend, which differs from the previous because it seeks to unite the small piece you create between shots and the other when we initially picked up the shots.

Choosing the first option, which is also the fastest in a time of software creation, also has the ability to generate the star-trails with a creative effect that does look like the rotation of many comets, and that we show for completeness.

While the classic mode, no falling star with the checkbox with the tick, looks like, for comparison in this version with the final touches applied cosmetics:

We have reached the end of this guide, hoping to have done something to please and have you inspired to produce your first Startrail, and I refer you to other posts of our Blog.

Hello and good job!