Optimal Camera Settings for Astrophotography

Photographer taking pictures of stars Milky Way night sky illustration

Anyone who’s tried to capture photos from the sky at night will know that it’s an obstacle. If the camera’s settings aren’t up to par it could result with a dark image blurred in motion, unfocused corners. The problem gets even more complicated in the event that you desire an accurate foreground or if you want to take photos of deep-sky images from distant stars. I hope this article will provide you with a clear idea of how you can set your camera to be able to capture astrophotography properly.

Before you dive too deeply into specific tips, keep your mind in the present that these strategies that are described in this article are perfect for taking sharp images of stars in a landscape photography viewpoint (where stars aren’t all that you see in your photograph). If you’re interested to shoot astrophotography using a telescope or anything similar to star trails in a landscape photograph it is possible to look for more specific information other than the settings for your camera below.

Milky Way with Person in the Foreground
NIKON Z 6 + 20mm f/1.8 @ 20mm, ISO 1600, 20 seconds, f/2.0

Focal Length

It is possible to shoot nighttime images with any focal length however, it is dependent on the type of picture you’re planning to shoot.

If you’re looking for a classic landscape that has your eyes focusing on the Milky Way overhead, and you’re looking to make everything as sharp as you can The best option is to make use of your largest lens. Ultra-wide lenses provide a couple of important advantages when shooting stars at night. Since they’re broad, you’ll have the ability to capture greater portions of the Milky Way in your images. Additionally, since wide lenses offer greater depth of field which means you’ll have a better process of making the foreground appear sharp. Furthermore the wide lens lets you make use of longer exposures before you notice any blurring due to star motion, letting you capture more light.

Personally, my preferred lens for this style of photography is 20mm and larger, however longer lenses can be useful as well. If you’re not averse to blurry stars – or are determined to capture the effect, you may want a larger focal length. For instance, I took the photo below at 85mm (and employed a particular lengthy exposure) to capture motion in the stars:

Long Exposure at Night
NIKON D800E + 70-200mm f/4 @ 86mm, ISO 100, 136 seconds, f/5.6

If you’re performing deep-sky astrophotography instead in an attempt to get distant objects captured within the skies, then a long lens is the best option.


  • Make use of a wide-angle lens to get as much sky as you can, increase the depth of field and utilize higher shutter speeds.
  • When you’re in the process of capturing motion blurring in the sky or you own an Equatorial mount (to help compensate for Earth’s rotating) choose the focal length you think is best to your design.


Normally aperture is one of the settings that you need to think about the most when doing photography, especially in the case of landscapes. When it comes to astrophotography however it’s less difficult because you’ll nearly always need the largest aperture of your camera (or within it).

The stars are too dim to warrant you to do everything you can to get the stars as bright as you can. The ideal aperture should be f/2.8 or greater, but lenses with an aperture of f/4 could work in the pinch.

However, using the lens’s widest aperture can cause some problems. The most important one is the fact that the quality of your photo isn’t as high particularly around the corners of your photograph. If you’re also adding a foreground to your photo, the smaller depth of field may not be the best choice.

Therefore, if the maximum aperture of your camera falls similar to f/1.4 or f/1.8 You may want to check and determine how it performs at these apertures. Pay attention to Vignetting (dark edges) and Coma (smeared star-shaped outlines in corners). If one of these problems are particularly bad you might want to choose an aperture that’s about 1/3 or two thirds of a stop less. However, if the maximum aperture of your lens is f/2.8 or f/4 generally, it’s not wise to reduce the aperture down further – just 1/3 stop or less since you’re already low in light.

You’re trying to balance two goals to capture sharper corners and collecting more light. There’s no one right solution, and it will depend on the lens and your personal preferences. If you’re not sure, it’s possible to shoot photos with a variety of aperture settings while in the field.

Personally, since my primary wide-angle lens can reach an aperture of f/2.8 and that’s the standard aperture when it comes to astrophotography. However, when I shoot Milky Way images using the Nikon 20mm f/1.8 lens I’ll choose anything between f/1.8 to f/2.2 in accordance with the compromise I’m willing to make for a particular day.

Milky Way over Grand Teton National Park
NIKON D800E + 20mm f/1.8 @ 20mm, ISO 3200, 20 seconds, f/2.2

If you’re shooting deep-sky astrophotography, then you’re more flexible. However, larger apertures are still recommended, as they can reduce the time of exposure significantly. Based on the quality of your lens and the lightness that your subject is, you should use an aperture between f/2.8 up to f/5.6. It all depends on your subject.


  • Make sure to shoot at the largest aperture possible setting, especially in the event that the lens’s maximum aperture falls within that range from f/2.8 to f/4.
  • If the lens’s maximum aperture falls within the region of f/1.4 up to f/2 this advice applies – however, make sure you’re happy using the appropriate amount of vignetting and coma in your photographs. To achieve more sharper corners but with the disadvantage of getting the most light possible make sure you choose an aperture which is 1/3 to 2/3 stop smaller.

Shutter Speed

The second among three “big three” settings is the shutter speed. This is essential in determining the brightness of your nighttime photos as well as how much motion blur is present that you can see in the night sky.

Stars are moving faster across the sky than one would imagine. While it’s great to take multiple minute images of the Milky Way to capture as many light-filled images as possible but you’re limited to a much lower shutter speed for stars that are sharp (and even if you don’t have an mount that is equatorial).

What length the shutter could you set before capturing motion blur? It’s dependent on a range of elements.

As already mentioned is the focal length. Larger lenses let you make use of longer shutter speeds prior to when you begin to notice changes within the stars. Another factor is the direction that you’re facing as stars move slower in the direction of Celestial North and Celestial South (essentially the North Star if you’re in the Northern Hemisphere).

Another thing that can affect the speed of your shutter is your personal decision to allow motion blurring in your photographs. There are photographers who cannot stand motion in their photos. The shutter speeds they use at night could be as low as five or 10 seconds. Others photographers don’t worry about star motion as much and are more likely to increase the shutter speed into the 20-30 second range to get the exact same shot.

But, there’s an element of diminishing returns. When the star is entirely away from its original location A slower shutter speed will not make it appear brighter (aside because of the impression that it appears brighter caused by its blurred, larger size). As many photographers want to get the most dim stars feasible, it’s crucial to be aware that an extremely long shutter speed isn’t the best solution (again in the case of not using an mount that is equatorial). Instead, it could increase background light pollution, harming the brightness for the starry night sky.

In the end your shutter speed should be within the range of 10-25 seconds for the majority of nighttime photography, and you could have faster or slower shutter speed based on the circumstance. Personally, using my 14-24mm f/2.8 lens, I prefer to shoot at an aperture speed of between 20 and 25 seconds, however it depends on the picture.

Astrophotography Example
NIKON D800E + 14-24mm f/2.8 @ 14mm, ISO 3200, 25 seconds, f/2.8

The best option is to simply trial and error on the field. Simply take a couple of photographs to test whether you’re happy with the amount of blurring that the stars create before moving on towards the artistic aspect instead. While there are calculations that can help you determine the best shutter speed that are extremely accurate and take the direction of your photography into consideration – it’s generally easier to just make a guess and then check. (Though it can be complicated when you’re changing directions often or constructing a panorama across a large expanse of the sky.)


  • The amount of time depends on factors like composition and focal length it’s typical to be between 10-25 seconds if you want the stars to be clear.
  • It is possible to use calculators with in-depth features to determine the ideal shutter speed, however it’s generally easier to take a guess and test.


It’s not easy to determine the best ISO for quality images in photography. This is applicable to The Milky Way as well. There are two school of thought in this regard:

  1. Take a photo at an ISO that will give you a photograph with the appropriate brightness. This is usually between 1600 to 6400 since it’s so dark at the night.
  2. Make sure to shoot at an ISO that will stop as many stars as you can to “blowing out” generally within the range of 100-400.

It’s generally recommended to follow the exact procedure you’d expect to do and shoot at an extremely high ISO to capture nighttime photos. Even though it might sound odd, there are instances where you’ll need to take Milky Way photos with a base ISO (resulting to a dark image) and then brighten it up after-production.

This explanation is more in-depth than the majority of photographers are required to think about. But, I’m putting this explanation because some of you might be interested in learning what it takes to get stars in the most color-rich detail feasible.

Particularly, certain cameras are ISO and are invariant even at low ISOs. This means there is no differences between brightening the image in camera with the higher ISO than brightening the image using post-processing software such as Lightroom and Photoshop. The concept of higher ISOs on camera can smudge some details in the sky and you could prefer to shoot with the lower ISO and then brighten it later, if you’re able to do so. If your camera happens to be ISO invariant, there’s not an negative impact on image quality when you shoot at ISO invariant. (It’s important to note that the majority of cameras aren’t ISO invariant to an excessive degree, however there are some that have a close relationship to.)

Low ISO Nighttime Photo
NIKON D800E + 14-24mm f/2.8 @ 14mm, ISO 200, 25 seconds, f/2.8

Personally my Nikon D800e is near ISO invariant, which is why it’s something I may do. But it’s not completely constant at the lower ISOs which is why I generally avoid this approach. I use higher ISO values instead, for example ISO 1600 (the the highest “real” ISO on my camera as I explained in the ISO invariance article).

It’s probably the direction you should follow too – just use the highest ISO and don’t worry about it any further – except if you are familiar with the particulars of your camera’s sensor and would like to get the extra bit of clarity in your photos.


  • A majority of photographers will shoot at the ISO value produces photographs that are bright and nighttime, generally between ISO 1600 to 6400.
  • If you are certain that the sensor on your camera is ISO invariant across a large portion of the range it may be better to shoot at the smallest ISO that is constant (the most “real” ISO) on your camera, and then enhance the image after the photo has been processed.

Other Settings

While these are the most crucial camera settings to be aware of for astrophotography the only ones to be considered. The most crucial choice is taking pictures in RAW instead of JPEG obviously. If you’re not already doing this – particularly when you have to work at night check out our RAW comparison with JPEG guide.

It’s important to remember that some settings for cameras don’t alter RAW images similarly to JPEGs as they’re not integrated into the file thus your selection will not affect your final image quality. This is especially true for things such as higher ISO Noise reduction and white balance or Picture Control/Style. If you’re shooting RAW and not converting to RAW, you will have less to worry about when shooting in the field.

Moon and Stars
NIKON D800E + 20mm f/1.8 @ 20mm, ISO 1600, 15 seconds, f/1.8

But some settings behind-the-scenes can still impact RAW images, such as one designed to be used in astrophotography. Long exposure and noise reduction. This option allows you to take two pictures in succession – the first of the scene that is in front of your eyes, the other of one is a “dark frame” without any content. The dark frame might appear empty, but it’s actually filled with noisy as well as bright pixels that are identical to the one in the previous picture. Your camera will subtract this dark area from your original image, which results in the image being cleaner.

Noise reduction for long exposures can have an impact on RAW images making it a crucial setting to be aware of. Since it is required to take two photos in succession and doubles the amount of time making each image. This may not sound bad, but it could be quite a hassle over time, and become quite irritating. Some photographers instead capture dark images themselves and then subtract the dark frames in their post-processing software. Some leave it turned off. Whatever you decide to do, it is helpful to be aware that noise reduction over a long period of time is a possibility.

This concludes the most important settings for cameras. If you’ve centered properly and are shooting RAW the only things you have to think about is shutter speed, aperture, and ISO not much different from normal photography. The only thing you need is a great composition.


  • Shoot RAW and not JPEG to get the best quality of the image.
  • Utilize the long-exposure noise reduction when you’re willing wait for twice as long per photograph in order to minimize heat and noise.


Nighttime photography can be a difficult job, and this article is only scratching the edges of what you can accomplish. (That ought to be evident given that we have Hubble Telescope! Hubble Telescope!)

My wish is that the recommended settings below will provide you with a clear starting point with the astrophotography you want to do. These guidelines will differ based on the type of shot you’d like to capture obviously – like a wide-angle panorama or a deep-sky photograph however, everything is focused on the capture of the light.

Nikon Z6 with F-mount 20mm f1.8G Milky Way
NIKON Z6 + 20mm f/1.8 @ 20mm, 20 seconds, f/2.0, ISO 3200

If you have any concerns or tips for helping fellow photographers take excellent Star as well as Milky Way pictures, please be sure to leave an answer in the comments below.