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I have quite often viewed widefield astrophotographs with terrestial objects in frame, most commonly mountains.

Based on what I have learned on astrophotogrphy, it seems like these photographs must be heavily composited and edited.

Is this the case?

For example, to achieve these extremely detailed milky way photographs, you must use extremely long exposure times, where your tripod compensates for the earths rotation, to prevent star trail.

So in this case the camera would move during exposure with the stars, and blur the terrestial object.

Or in addition you can do take many frames, and then align and stack them in an image stacking software. But in this case, the images will be aligned based on the star locations based on earth rotation, and again the terrestial object will be blurred.

So the only way I can see these photographs being done, is by manually editing the terrestial and stars apart, and processing them separately, then compositing together.

Is this the most common way to acheive astrophotographs with terrestial objects in them, that are not blurred?

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    Possible duplicate of How to get the bet results for landscape and stars photographs? – mattdm Nov 27 '17 at 2:49
  • Nothing in that thread comes close to my much more specific question. The title implies the question might be similar but the to other question and all of its answers are basically "how do you do astrophotography 101", where as my question goes into more specifics of theory and the most specific problem of matching terrestial objects and rotating stars. – ScottF Nov 27 '17 at 2:59
  • FYI terrestial object means an earth based object, in case you were confused and thought I was asking about how to prevent start blur. – ScottF Nov 27 '17 at 3:05
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    Yes, I know what terrestrial means. The other question says "I'd love to take some picture of the landscape: the starry sky + the surrounding mountains' silhouettes.", which seems identical to what you're asking. – mattdm Nov 27 '17 at 4:10
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    You're right though that that question has some pretty meandering answers that don't seem to really address this. Since it was such an old question, it asked for "tips" as well. I've edited it to correct that. This site isn't really a discussion forum and these aren't "threads" — old questions should still be relevant and interesting, or they should be deleted. It's better to have one question with solid, ranked answers than having a bunch scattered around — that's what the duplicates mechanism is for. – mattdm Nov 27 '17 at 4:13
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Based on what I have learned on astrophotogrphy, it seems like these photographs must be heavily composited and edited.

Is this the case?

It depends. That is one way to do it. It is perfectly possible to take a photo of the Milky Way with mountains in frame without using a moving mount.

This website shows how to take widefield photographs of the Milky Way and terrestrial objects using only a normal tripod and DSLR.

Here's one I took at Zion National Park:

The Watchman & Milky Way

This required the following things:

  • A camera that has good low-light capabilities - in this case a Canon 5D Mk III
  • A wide, fast lens - A Canon 16-35 f/2.8 L
  • A moonless night
  • Very little light pollution, but enough terrestrial light to make the mountain visible
  • A tripod
  • A 25 second exposure
  • ISO 6400
  • Post-processing to bring out the Milky Way

You can go to more trouble to get even better photographs, though. It is possible to make a panorama of the night sky. It does involve taking multiple very long exposures with a moving tripod, then combining the images together and working on the terrestrial part separately from the star part. But it's not required for all types of photos.

One other thing I forgot to mention is that the time of year also make a huge difference. The above picture was taken in June, in the Northern hemisphere. I have another one I took in November about a mile or two from that one, and while you can see the Milky Way, it's much less spectacular. So wherever you're located, make sure to check whether the things you want to photograph will be visible in the night sky and whether they'll look their best.

  • Ok so you didn't use a massive exposure time (enough to get star trails) and you didn't use stacking? Wow I thought for sure to bring out the milky way you needed both of them. I guess since I am using a canon t3 and f4.5 aperature, I will probably need those techniques. – ScottF Nov 27 '17 at 15:21
  • Right, no stacking at all. The other thing to keep in mind is that a t3 is APS-C which is a crop sensor, so a 20mm lens will act more like a 30mm lens. So you want a very wide lens. One nice one that I've used on a crop sensor is the Tokina 11-16mm or 11-20mm. At 11mm they act like ~16mm, which what I used on a full frame in the above image. – user1118321 Nov 27 '17 at 17:12
  • I have the canon 10-18mm, which unfortunately is rather slow. – ScottF Nov 27 '17 at 17:20
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    The amount of light pollution or lack thereof has as much, if not more, influence on the ability to capture details of the Milky Way as the difference between the 5D Mark III and the T3 does. – Michael C Nov 28 '17 at 1:00
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Yes that is exactly how it is done. YouTube has several videos on the subject. The stars and the land are processed separately using stacks and then combined. It is a fairly complicated process to describe here. I have done it several times and it does take a while and a fair bit of processing power. I haven’t gotten any great results since my camera only goes to ISO 1600 and my aperture to f3.5 I have needed to leave the shutter open far to long resulting in Star trails. I am mostly working on the technique and once I have it down I will rent a better camera and lens.

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