Is a 50mm lens good for astrophotography?

Although many photographers may prefer wider lenses in astrophotography to be able to capture as much of the night sky at once, there are some photographers passionate about 50mm photography which is kind of my expertise.

It is a 50mm lens good for astrophotography? With a 50mm lens, you are able to photograph only part of the night sky and one of the main uses of a 50mm lens is to capture constellations such as Orion. Following the rule of 500 in astrophotography, you may not be able to hold an exposure longer than 10 seconds without to induce star trails, but with a 50mm lens, you are also able to capture details other wider lenses can’t.

A large impact can have the aperture of the 50mm lens and if the lens is mounted on an APS-C sensor camera or full-frame camera. With a million and other factors which can influence the quality and the performance of a 50mm lens and camera in astrophotography, in this topic, I am going to underline the most important ones and help you improve your 50mm astrophotography with a step-by-step guide.

It is a 50mm lens good for astrophotography?

There are more advantages than disadvantages of using a wider lens in astrophotography than a 50mm lens. Now, because you are reading this topic, that means you are either interested in capturing the night sky with a 50mm lens because either you have one or you want to buy one.

To capture the night sky in general either with a 50mm lens or with any other lenses, the quality of your DSLR and ISO capabilities can make a difference, as well as the region you are capturing the images. Nowadays, it is hard to find any areas with no light pollution where sometimes you may have to drive dozen of miles away from the civilisation only to get that beauty of the night sky.

Furthermore, let’s explore together the key points of using a 50mm lens in astrophotography.

The Aperture of a 50mm lens used in astrophotography

Oh yes! I own a Nikkor 50mm f/1.2 manual focus lens and let me tell you this: I am absolutely amazed by the results not only in photographing the night sky but in general photography with this lens.

It does matter a lot the aperture when you are photographing the night sky with a 50mm lens, as much as it matters the performance of the camera you own.

• As an instance, most of the 50mm’s have an aperture of f/1.8 which is quite okay but you may need to boost the ISO a bit in order to get some details of the night sky.
• A 50mm lens f/1.4 will definitely do better than the f/1.8 version and more details are captured with a lower ISO number.
• In the case of a 50mm lens there may be a very few with the aperture of f/1.2 as the one I own, and this in astrophotography will do amazingly, isn’t it? It is a yes and no in the same time.

Yes with an aperture of f/1.2, you will be able to capture amazing details of the night sky without to boost the ISO too much.

No, you will probably have to step down the aperture as on f/1.2 you will get a lot of barrel distortion and vignette.

Photographing at f/1.2 you can capture a lot of details of the night sky but may not be such as a good idea as a lot of vignette and distortion may be present which is heavily noticeable in astrophotography. (please check the above image for a reference)

One of the problems when shooting in astrophotography at an aperture of f/1.2 is that the stars will look stretched by the edges. At least this happens on a full-frame camera where all the aperture is being used.

The solution would be simple to step down the aperture to f/1.4 or f/1.8 which will have an incredible advantage over the lenses with their maximum aperture of f/1.4 or f/1.8. The benefit is the sharpening increases a lot, there are less distortion and vignette.

50mm lens on APS-C or full-frame sensor for astrophotography?

The APS-C sensor cameras have a crop rate of 1.5x, therefore, a 50mm lens will become 75mm while a full-frame camera maintains the same focal length values. Moreover, most of the 50mm lenses are designed to be for a full-frame camera and although you are able to mount it on an APS-C camera, you may have advantages and disadvantages at the same time.

One of the advantages is that the size of the glass in an full-frame 50mm lens, when mounted on the APS-C sensor camera, is that you will remove the vignette as the lens have a larger surface for capturing the light, but a portion of the light is also lost.

In astrophotography, with no doubt, a full-frame camera will do much better than a crop-sensor camera. But this does not mean you are not able to capture the night sky with an APS-C sensor.

How to take photographs of the night sky with a 50mm lens?

This is a step-by-step guide on how to take photographs of the night sky with a 50mm lens, covering both full-frame and APS-C sensor cameras.

1. Ensure that the region you want the photography session is having low or none light pollution otherwise the images will suffer on quality.
2. Place your camera on a tripod and set your lens to manual focus mode.
3. Set your camera on manual mode to have control over the aperture, ISO and shutter speed.
4. Find a bright star using the live view mode, zoom in and focus manually until you get the maximum sharpness. Watching through the viewfinder may be a good alternative but the stars will appear dim and you may not be as accurate on focusing as watching through the live view mode. If your live view mode is unable to observe any stars, pick a distant light instead.
5. Switch off the live view mode and put your shooting mode in mirror-up to decrease the shake amount induced from the mirror.
6. Aim your camera to the part of the night sky or constellation you intend to photograph.
7. Set the aperture to the widest for your lens (later try to step down the aperture) and for a full-frame camera set the shutter speed to 8 seconds, where for a APS-C camera the shutter speed to be around 6 seconds (the reason we decreased the shutter speed is to ensure the maximum sharpness)
8. Further, set your ISO manually to values between 2500 and 6400 depending on your camera model and capabilities. Lower the ISO = less noise into the image.
9. Take a test shot. Remember to click twice the shutter button due to the mirror-up function. It is a good practice to have a shutter release cable to a remote control. Check your image and zoom in, see if there are any settings to be adjusted and if the sharpness is okay.
10. Now is time to take about 8 exposures one after another (less is okay but more the better) this will be later used in post-processing.
11. After that, readjust the camera angle, capture the night sky as you like with a number of exposures until you drain your battery (like myself).
12. When back at home is time for post-processing. There’s a complex guide on how to use exposure stacking and manual star alignment in photoshop. I recommend you to check this external YouTube guide for more info.

Please keep in mind that you will need to have Lightroom and Photoshop, as well to shoot in RAW and NOT JPEG. The reason for using exposure stack is to reduce as much as possible the noise produced of having high ISO and the manual star aligment is the best approach to align the exposures right.

What you can capture with a 50mm lens?

As mentioned above, you are able to capture only part of the night sky, therefore, one of the best uses of a 50mm lens is to capture different constellations.

Also, capturing different objects in the night sky and due to the high camera resolution, you are able to crop a bit from the image in order to get a specific part of your image as in the photograph above where you can see the M31 or Andromeda Galaxy. This was captured with a 50mm lens on a full-frame camera.

Choosing the right nifty fifty for astrophotography

There are many camera models on the market and manufacturers and as mentioned, for sure, a full-frame will work better than an APS-C camera due to the larger sensor, but even better than that would be the special cameras for astrophotography such as the Nikon D810A which can captures nebules emitting the H-alpha wavelength.

The performance of a camera can make the biggest impact in astrophotography but a good quality 50mm lens can also play a major role.

A 50mm lens with the widest aperture can be a good choice as the Nikkor 50mm f/1.2 manual focus lens due to the possibility to step down the aperture for extra sharpness and to remove the side effects of a very wide aperture lens but there are other factors to take into consideration.

One of the factors should be the sharpness overall of a lens, if the lens have ED elements and one more important which I didn’t mention before, for the lens to be a prime lens and NOT a zoom lens.

Zoom lenses will have a narrower aperture, more glass will affect the amount of light it captures on the night sky and the sharpness of a zoom lens is inferior to a prime lens. There can be a very few specific zoom lenses which can be used in astrophotography and still give you a good result but nothing covering the 50mm focal length.

When a wider or telephoto lens would be better for astrophotography?

If you are passionate about astrophotography and/or capturing the night sky, you should have in your backpack a few other prime lenses, and the ones I do recommend would be 14mm, 18mm, 35mm, 50mm, 105mm and so on.

You have to keep in mind that the wider the lens can capture, you are able to expose the night sky for a longer period of time as following the rule of 500 in astrophotography. More telephoto is the lens, less light can be captured before the star trails become visible.

As an instance, with a 14mm lens on a full-frame camera, you can capture the night sky on a 35sec exposure before star trails become visible, which allows you to lower the ISO and get images with less noise, wherewith a 105mm, you can have an exposure of a maximum of 4.7sec, roughly 5sec but recommended 4 for extra sharpness.

Conclusion

Having a 50mm lens in your backpack is a good thing even for astrophotography. My favourite lens is the 50mm mentioned above and I won’t trade that for anything else, even in astrophotography, this lens can have a good usage.

But that is only my opinion and every photographer have a different one. If you already own a 50mm lens there is no reason why you should not use in capturing the night sky. Remember, the 50mm lenses are very cheap & good compared to many others.

Thank you for remaining until the end of the post. I hope to see you around.