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54

Stars move. Like with any other movement, what we care about is how much they move on the sensor during exposure: A movement that occurs only within a single pixel is not a movement the sensor can capture, i.e. the movement appears frozen. But when movement takes a point across several pixels during the exposure, it will be visible as movement blur, in this ...


41

Stars don't show up voluntarily on a photo. You need to tweak them a bit using photo editing tools on a computer. Best if you use RAW file format, and RAW-processing software to do this. JPEGs can be tweaked to show more stars, but with a lot less working room and result being of lesser quality. The likely JPEG image you get with the exposure settings you ...


26

Along with weighing down the tripod, using a cable to release the shutter will help reduce camera movement. Also, if you want to guarantee no mirror shake happens during the exposure, hold a black object in front of the lens while triggering the shot, then pull it away for the duration of your exposure.


24

They are not uniform but they all show the same bright-dim-bright pattern. One explanation is that this is a composite picture of several exposures and that the middle exposure(s) was/were dimmed a bit to compensate for a brighter subject (booster separation).


22

Mirror slap is an issue in "medium" long exposures - from 1/30 or so til about a second or two. Tripod shake is issue in "long" long exposures - from about a second upwards. For shooting stars you can safely forget about the mirror slap. It will last about a second of the four hours exposure. Nothing of importance will be captured in such a short time. ...


19

Johann3s' answer is good, and covers all the basics. When it comes to the milky way, which is a form of ultra wide field night sky astrophotography, you want to use the highest ISO you can get away with, the longest exposure you can get away with, at the fastest aperture your lens supports. Here is a little bit more detail. The Technicalities Which ISO to ...


17

Mirror slap will last some fraction of a second. This is completely irrelevant in a multi hour exposure. Weighing down your tripod is a good idea nonetheless, since movement from wind will be a bigger risk.


13

In order to photograph the milkyway you want to capture as much light as possible within a certain timeframe. This means: Highest ISO you think is acceptable with your body Widest aperture Shutter speed as long as possible, without setting it too long so you can see the movement So looking at your settings, indeed the aperture could have been wider, like ...


12

In fact, if you spend the night in a remote enough place with clear, moon-free sky you will see most of the colors. The sad truth is that most of us live in cities where light polution and smog do not let us see anything except the brightest stars.


12

There's always the old Hat Trick: Take your hat (or anything blocking light, a piece of cardboard, the dew cap of your lens etc.). Hold it in front of the lens to prevent light to reach your film. With the hat still in place, release your camera's shutter. Wait until mirror slap and tripod shake have faded. Remove the hat without disturbing the camera. You ...


11

The rule of 600 states that to 'eliminate' star trails the exposure time in seconds should be 600 divided by the focal length of the taking lens. 20mm lens could go to 30 seconds, 300mm lens could go to 2 seconds. Of course (like any motion blur) you will never eliminate star trails- you merely reduce the trail to an acceptable level for a given enlargement....


10

An equatorial mount and a computer controlled mount are two different things. A mount can also be both. A equatorial mount has one axis aligned with the spin of the earth (pointed towards Polaris for those north of the equator.) A computer controlled mount is a mount that knows where the objects in the sky are. You can say, "point at Jupiter" and it will ...


10

Simple answer to your main question is: The Dynamic-range of the sensors of current digital camera is not yet a match for the dynamic range of human eye's sensor (aka retina). Detailed answer of "how to bring it up" will bring all the techniques on the table. The majors are: Widest possible aperture on lens, if possible f/1.8 or f/1.4 Widest angle: To ...


9

The photographer notes in the description: 'I separately captured the bridge about 2-3 shots with different exposure and blended them later with the star trails shot in Photoshop.' In other words, the bridge shots weren't 180 second exposures.


9

You can't see the colours in the milky way (or other stars for that matter) as the light coming from the milky way is too dim to be picked up by the cone cells in our eyes which distinguish colour. Instead the light only trips the more sensitive rod cells (which are usually used for detecting motion) hence we see the brightness but not the colour of the ...


9

Camera is better at seeing than our eyes. According to http://www.cambridgeincolour.com/tutorials/cameras-vs-human-eye.htm astrophotographers have estimated that human eyes have a ISO rating of 500-1000 after being properly acclimated to dark conditions. The example photograph has used something like ISO 3200. Cameras can also take longer exposure (=gather ...


9

It is probably easier to talk about what qualities in a lens that often add significant cost that you don't need in order to do astrophotography. The first is Auto Focus. Stars are such tiny points of light that the accuracy of most AF systems is not quite good enough to resolve them to the absolute sharpest capability of the lens. Most AF systems can't ...


8

Are those other planets or other stars? Or is that a lens effect? Looks to me like a planet and some moons. I don't know where you are, but Jupiter has been very bright in the night sky lately in my neighborhood, and with a long enough lens it's not hard to see some of its moons. Seen through a sufficiently powerful telescope, a planet looks very different ...


8

The example image in your question is probably affected by geometric distortion which is a property of the lens' projection of an image of a three dimensional world onto a two-dimensional image plane. This distortion is exaggerated by placing the axis of rotation off-center in the frame. The "wild" looking images at the link in the question appear to have ...


8

Looks to me like you might have forgotten to turn off image stabilisation in camera and/or lens. Image stabilisation uses acceleration sensors to estimate movement/shake of the camera/lens and then moves optical elements or the sensor to compensate. On a tripod, this does more harm than benefit since errors in the estimated movement accumulate and cause the ...


7

Finnish night sky is now dark enough to photograph stars (it is September now) so I went to try my first shots at stars. I have never tried to take a photo of stars before. My photos turned out even darker than yours, but I was more daring with my post-processing and I think I now know what is wrong with your photo. Post-processing! Naturally that is not ...


7

The "basic gear" is a digital camera and tripod. Point the camera at the sky for 30s with the aperture wide open at the maximum ISO setting. With the right atmospheric conditions and location you can get some surprisingly good results. Moving on from there a DSLR with RAW support (the 60D is fine) fast lens (such as a 50mm f/1.8) is advisable, as well as an ...


7

Its probably due to a narrow aperture. On professional grade lenses, you can usually stop down a bit and still maintain a rounded aperture, however on cheaper lenses, or on all lenses at very narrow apertures, the opening becomes polygonal. That causes the diffraction of light as it passes through the aperture to produce a star pattern (the exact nature of ...


7

I think the main cause of that effect is using a very small aperture. If you're trying to get a long exposure by stopping down to f/22 or smaller you'll most likely get that effect.


7

I don't think this is a tripod stability problem. The star trails are all straight, not wiggly as they would be if the camera where moving during or between each exposure. The dimmer stars are easy to see as nine distinct dots. None of the dots indicate camera movement during any of the nine exposures, and none of the lines of the nine dots for each star are ...


7

I agree with the comments made by JohannesD. It is easy to see that your tripod moved, when you magnify the picture of the stars. You can clearly see that the star trails are not small circle segments, instead they have an irregular curvature which is indicative of tripod movement instead of the usual trail casued by the rotation of the Earth. It is ...


7

shined a light to focus on foreground beforehand If you focused on the foreground then the most likely explanation is that the stars are blurry because they are out of focus, at f/4 the depth of field is not sufficient to contain both the foreground and the stars (which are effectively at "infinity" or as far away as you can get). I would recommend you try ...


6

If you have an android phone with geolocation and compass, Google nightsky is outstanding. Or if you're on your computer http://www.google.com/sky/ google sky. I'm sure you could find better software for the task, but if you're just trying to get the milky way or a constellation or two, it will do the trick.


6

This technique is called "Startrails" and you don't need to have a special camera. All you need is: - tripod - time-lapse control to shoot lot's of photos - fast lens (large aperture) - compass - startrails software (it's called Startrails.exe and you can find here) Your camera will shoot for a long time (it depends how is the effect do you wanna get, in ...


6

Don't use in-camera white balance. Have the camera produce a raw file, then you take it from there. You can measure the white balance of your sensor ahead of time, then use that correction for the star image. For something like stars, I'd use sunlight as the white reference. Put another way, sun-like stars will appear white and other stars will have ...


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