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This question already has an answer here:

so I tried to take pictures of a house and the night sky, but everything came out very blurry no matter what I used

I shot at 30 sec exposure, F 3.5, ISO 3200 on a tripod using remote

enter image description here

marked as duplicate by mattdm, NickM, Hugo, inkista, Philip Kendall Oct 22 '15 at 8:47

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Does your lens have VR?

If so try turning it off. If that's a 30 second exposure you're on a tripod which is good.

  • If you have an ML-L3 remote or knock off, put the camera on remote.
  • The in the shooting menu set the remote mode to Mirror Up. Put your camera on the tripod and turn it on.
  • Set the VR off and turn off the AF.
  • Turn on Live View, and zoom in on whatever it is you want to focus on. -If you can't see in live view turn the ISO up to as high as you need to.
  • Focus and frame your shot.
  • Once the shot is focussed and framed, turn the ISO back down to whatever you want to shoot at (I suggest ISO 100).
  • Set the aperture if necessary, I'd suggest ƒ/8-ƒ/11.
  • Hit the remote button once, that will raise the mirror
  • wait about 30-60 seconds to allow any vibration/harmonics to settle
  • hit the remote button again, this will fire the shutter

If you don't have a remote you can use the Timer release mode. If possible set it to around 30 seconds. Then carefully push the button as gently as possible. The camera should wait 30 secs then fire.

Things that move, e.g. trees in the breeze will be blurry. The stars may start blurring too - the earth is spinning.

But aside from moving objects that should get you a fairly good shot as long as there is no wind to wobble the camera/tripod.

  • Jason Tan, thank you for your reply. I'm using a tripod and a remote. I will check VR although I am not sure I have it. I also appreciate a very detailed answer about focusing. I couldn't figure out how to do it manually at night. – user173570 Oct 21 '15 at 11:53
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You should have focused manually on the background stars. You then have to magnify the picture and then focus on a star, the star should change from a disk to just a point when optimal focus is achieved. This would have improved the picture, but the depth of field may not have been sufficient to get the house in the foreground in good focus. A smaller aperture of, say, F/8 would have been better, that would also have reduced the blur due to lens imperfections while you would not yet have had any diffraction blur. The ISO value would have had to be chosen larger, say, 16,000. To reduce the noise to acceptable levels, you could then have taken, say, ten pictures and then using image stacking methods, aligned the pictures and then the average would have been a low noise image.

Now, using the picture you took, it is possible to correct for the unsharpness using deconvolution by using the stars as the point spread function. I took an average of 6 stars to calculate the point spread functions and used that to deconvolve the image:

deconvolved image

This should ideally be done on the original image, not the jpeg version as that causes the jpeg artifacts to be enhanced as well. Also, the image was likely resized, no star trails were visible despite the 30 seconds exposure. If you want to do deconvolution on the original image, then you cannot use the stars as the point spread functions, although you could first deconvolve images of the stars using line segments with the length of the trails as point spread functions to get to the desired point spread function with which you can deconvolve the rest of the image.

To avoid getting star trails in the image requires using a shorter exposure time, at a focal length of 17 mm, you can expose for about 6 seconds.

  • Count Iblis, thank you so much for your reply. I shot using a tripod and a remote. I focused on infinity. I thought that the stars is pretty much infinity. How can I possibly manually focus on the stars at night? – user173570 Oct 21 '15 at 11:43
  • Live view, zooming on them. Or live view on the house. – FarO Oct 21 '15 at 14:29

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