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These photos are taken in pitch-black darkness. You need to take a lot of exposures in order to get the data necessary to even see anything.

rafram 1y ago
No, you need to take a long exposure. Multiple exposures may improve the quality but isn’t necessary at all.
- teamonkey 1y ago
  If the camera is stationary you must stack multiple short exposures to avoid star trails. You can only take long exposures with an equatorial mount.
  - littlestymaar 1y ago
    Not if your “long” exposure is just 10s long, which is enough to get those annoying starlink trails.
    - teamonkey 1y ago
      Sure, 10s is certainly long enough to capture Starlink trails, though 10s exposure is not especially long for an astro photo and you would typically want to take longer exposures or stack multiple shorter ones. For example, my Seestar S50 takes many 10-second photos to form one exposure. I would normally expect to take 1500 10-second exposures or more for a good picture, perhaps over mutiple nights (although this is very different to a wide-field image like this). A Starlink trail would be very visible in any individual frame, often brighter than stars, and I would expect to capture many individual frames containing starlink trails.
testing22321 1y ago
This is a single 10sec exposure in the Aussie outback on old consumer gear ( Sony a7iii ) https://www.instagram.com/p/CersLuLBfCz https://www.instagram.com/p/CersLuLBfCz You don’t need multiples, and you don’t need an overly long exposure.
- genewitch 1y ago
  It sounds like you know what you're talking about until one realizes the earth is spinning. Wide field photos can be shot up to thirty seconds depending on the back and lens. Anything more zoomy than 50mm uncropped you're getting streaks in < dozen seconds. There's a rule of thumb but I don't remember it. Best course of action is to take a video and let a stacking program deal with it, especially if you use a real telescope. Also the Sony a7r have like "150,000 ISO " and iirc cost like $3500 with a kit lens. That's a bit above consumer, but I may have mixed up models.
  - joshvm 1y ago
    Tens of seconds is about right. It's something like 500/f(mm) in seconds, but you get a feel for what will blur and what won't. Here's an example I shot with a Nikkor 50mm f/1.4 @ 20s: https://www.instagram.com/p/C-mU6iIp0re/?igsh=cm16bWx1cGp3OG11 https://www.instagram.com/p/C-mU6iIp0re/?igsh=cm16bWx1cGp3OG...
  - testing22321 1y ago
    My camera is not an a7r. I paid $1200 for it used. The exposure was 10 seconds, so by your own explanation, the spinning of the earth is not a problem ( as you can clearly see in the photo I linked )
    - teamonkey 1y ago
      An astronomy photo can commonly require hours or even tens of hours of exposure time.
      - testing22321 1y ago
        The noise from a single image of that duration would be unworkable. Even if there were no planes or satellites, nobody would take that as a single exposure.
        teamonkey 1y ago
deleted 1y ago
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t0bia_s 1y ago
This is not true. Image in article is taken (and stack from many images) during sunset/sunrise when satellites are lighted by sun while photographer is in dark. It's not that visible at night.

rafram 1y ago

No, you need to take a long exposure. Multiple exposures may improve the quality but isn’t necessary at all.

teamonkey 1y ago
If the camera is stationary you must stack multiple short exposures to avoid star trails. You can only take long exposures with an equatorial mount.
- littlestymaar 1y ago
  Not if your “long” exposure is just 10s long, which is enough to get those annoying starlink trails.
  - teamonkey 1y ago
    Sure, 10s is certainly long enough to capture Starlink trails, though 10s exposure is not especially long for an astro photo and you would typically want to take longer exposures or stack multiple shorter ones. For example, my Seestar S50 takes many 10-second photos to form one exposure. I would normally expect to take 1500 10-second exposures or more for a good picture, perhaps over mutiple nights (although this is very different to a wide-field image like this). A Starlink trail would be very visible in any individual frame, often brighter than stars, and I would expect to capture many individual frames containing starlink trails.

testing22321 1y ago

This is a single 10sec exposure in the Aussie outback on old consumer gear ( Sony a7iii ) https://www.instagram.com/p/CersLuLBfCz https://www.instagram.com/p/CersLuLBfCz You don’t need multiples, and you don’t need an overly long exposure.

genewitch 1y ago
It sounds like you know what you're talking about until one realizes the earth is spinning. Wide field photos can be shot up to thirty seconds depending on the back and lens. Anything more zoomy than 50mm uncropped you're getting streaks in < dozen seconds. There's a rule of thumb but I don't remember it. Best course of action is to take a video and let a stacking program deal with it, especially if you use a real telescope. Also the Sony a7r have like "150,000 ISO " and iirc cost like $3500 with a kit lens. That's a bit above consumer, but I may have mixed up models.
- joshvm 1y ago
  Tens of seconds is about right. It's something like 500/f(mm) in seconds, but you get a feel for what will blur and what won't. Here's an example I shot with a Nikkor 50mm f/1.4 @ 20s: https://www.instagram.com/p/C-mU6iIp0re/?igsh=cm16bWx1cGp3OG11 https://www.instagram.com/p/C-mU6iIp0re/?igsh=cm16bWx1cGp3OG...
- testing22321 1y ago
  My camera is not an a7r. I paid $1200 for it used. The exposure was 10 seconds, so by your own explanation, the spinning of the earth is not a problem ( as you can clearly see in the photo I linked )
  - teamonkey 1y ago
    An astronomy photo can commonly require hours or even tens of hours of exposure time.
    - testing22321 1y ago
      The noise from a single image of that duration would be unworkable. Even if there were no planes or satellites, nobody would take that as a single exposure.
      - teamonkey 1y ago

deleted 1y ago

[deleted]

t0bia_s 1y ago

This is not true. Image in article is taken (and stack from many images) during sunset/sunrise when satellites are lighted by sun while photographer is in dark. It's not that visible at night.