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Beginner’s guide to photography star comet



Comet C/2020 F3 (NEOWISE) has reached the night sky of the northern hemisphere, which delights both stargazers and photographers. Through planning, patience and clear skies, you can capture unforgettable images of this celestial event.

In the early morning of Saturday, July 11th, I took a picture of Stonehenge, with a comet glowing above my head, arguably the most spectacular picture of a luminous cloud dancing behind. I posted this picture online later that morning and I slept for a few hours. I awakened hundreds of comments, direct messages and emails from photo admirers who wanted to know where, when and how to shoot comets for themselves.

I hope this article will answer these questions for anyone else who wants to capture this rare astronomical cuisine.

The “England Stonehenge” above was taken with a Nikon D850 and Tamron 70-200mm f/2.8 at 102mm – f/2.8 – 2 seconds – ISO 1250. Use Starry Landscape Stacker to stack 6 frames; light crops

when and where

NEOWISE appears in the evening sky of N-NW. The ambient light in the sky after sunset may make it difficult to find at first, so here is a tip to locate the comet with the naked eye: try to defocus your eyes and quickly scan the sky, which can help you see the faint glow of the tail.

If you still can’t see it with your naked eyes, you can try to find it with a quick lens. I used a Sigma 14mm f/1.8 to take a wide-angle shot northward, and quickly found the comet’s tail for 10-15 minutes. Then I realized that it can be easily seen with my eyes.

No one knows how long NEOWISE will show at night. In theory, this comet should be visible in the evening sky in the northwest in late July, but this is not guaranteed, so please do your best!

equipment

The tripod is sturdy enough to support the weight of the camera and make it stand still for up to 30 seconds (depending on the width of your shooting), which is as important as the camera itself. A light travel tripod is a good idea. If you want to hike to a place, it may not perform so well during long periods of time or windy conditions.

If you can, use a fast fixed-focus lens for shooting-this will be the best option, because a large aperture can capture more light and more detailed images.

The area covered by the comet’s tail is larger than what the naked eye sees-I believe it is forgivable that you need a zoom lens. In fact, you can also get satisfactory results from a wider angle.

If you don’t have one, then fifty (50mm fixed focus lens) is often a cheap option, it can provide a pleasant focal length to capture comets, and its exposure time can be up to 10 seconds.

Finally, consider using a remote shutter, whether it is a wired or wireless cable. You can choose one of them cheaply on eBay instead of using the brand model of the camera manufacturer. When you press the camera’s shutter release button, you will introduce some motion, which may interfere with the image. Remote shutter can eliminate this situation. Or, check if your camera has a built-in timer. For example, when I set the Nikon D850’s timer to 5 seconds, I can use the camera shutter release button to shoot safely.

This is an idea about how comets look at various focal lengths.

35 mm

British Stonehenge. Nikon D850, Tamron 24-70mm f/2.8, 35mm – f/2.8 – 10 seconds – ISO 200. No harvest.

On a full-frame camera, you should be able to shoot for up to 14 seconds without dragging any stars.

50 mm

Tenby, Wales. Nikon D850, Tamron 24-70mm f/2.8, 50mm – f/2.8 – 6 seconds – ISO 800. No harvest.

On a full-frame camera, you should be able to shoot for 10 seconds without dragging any stars.

200 mm

Dryslwyn Castle in Wales. Nikon D850, Tamron 70-200mm f/2.8, 200mm – f/2.8 – 2 seconds – ISO 1600. Crop.

On a full-frame camera, you can only shoot for 2 seconds and then perform star tracking. This means you need a large aperture and high ISO to take good photos

Recommended apps and websites

Stellar

Stellarium is a free open source planetarium for your computer, and there is also a web version. You can enter the location and Stellarium can show you the sky at any time. Click NEOWISE and Stellarium will display the azimuth (direction) and altitude at a given time.

Clear outside

“Clear Outside” is a weather application for astronomers, it provides a detailed classification of cloud cover. It can be used online for free or as an iOS and Android application. Ideally, you want a completely clear sky, but keep in mind that comets can still be seen through cloud bursts (especially in the dense upper clouds).

Photographer’s Ephemeris

The photographer’s ephemeris is an excellent planning tool, available through paid iOS and Android apps, and can be used for free on the web-registration is required. Use this tool to draw your viewing position, the object you want to shoot, and then TPE will tell you the direction and height. Use it in combination with Stellarium to calculate NEOWISE’s position in the sky and how it works with the object you want to photograph.

Light hound

Finally, PhotoHound is a convenient tool that can be used to find important photo locations around the world-the reason I say this is not because I happen to be one of its co-founders! The web version is free to use-registration is required. Look for places of interest and see if you can use them in combination with NEOWISE to create compelling images. (And, when doing so, you are welcome to add it to the PhotoHound map.)

Composition ideas

Now that you have positioned NEOWISE in the sky, you need to decide how to shoot it. You can isolate the comet from the night sky, or look for interesting prospects. Here are some ideas for you to try.

Capture comets and landscapes

Welsh Llanllwni. Nikon D850, Sigma 14mm f/1.8, 14mm – f/1.8 – 20 seconds – ISO 800. No harvest.

This is the easiest way to photograph it, it has a wider lens and shows beautiful starry sky scenery.

Consider shooting from a higher ground, showing a pleasing view of the sky above and the land below in a single frame. This also gives you the advantage of avoiding low-level fog and mist that form overnight on the lower ground.

Shoot comets with objects or landmarks

Tor, Glastonbury, United Kingdom. Nikon D850, Tamron 70-200mm f/2.8, 200mm – f/2.8 – 2 seconds – ISO1600. Use Starry Sky Stacker to stack 9 frames; crop.

Find a famous landmark, building or other object and take a picture next to the comet! You need a combination of the above applications to find the right angle and time, but when these applications are beneficial to you, you will surely produce pleasant images!

Quarantine comet

Nikon D850, Sigma 150-600mm, 300mm – f / 5 – 1 second – ISO2000. Use Starry Sky Stacker to stack 9 frames; crop.

This is the trickiest thing because you need good zoom and the longer the focal length, the shorter your exposure time must be in order to avoid stellar tailing.

If you want to create a longer exposure than this, you need to use a star tracker. This is a very advanced technology, far beyond the scope of this getting started guide! A simpler option is to take multiple short exposures at high ISO and then use software such as Sequator or Starry Landscape Stacker to stack these frames to reduce noise.

500 rules

If you are not sure how long you want to expose, you need to check what is called the 500 rule, which is used to calculate the longest exposure time that can be reached before the star becomes blurred.

Calculated as follows:

500÷(Crop factor x focal length)=Shutter speed

When you shoot stars at 2 am, it may be difficult to understand, so this is a table with common focal lengths.

I hope this article will help you capture this incredible display in the next few days and the commemoration of this historic moment in the years to come. Astrophotography requires patience and technical ability, but the result is worth the effort. I like seeing photos of NEOWISE and taking photos of myself. You are welcome to tag me on social media to watch your work.


About the author: Mathew Browne is a photographer from South Wales and co-founder of PhotoHound. PhotoHound is an online photographer community that allows people to share information about the best photo locations in the world. The views expressed in this article are solely those of the author. You can find more works by Browne on his website, Facebook, Instagram, Flickr and 500px. This article is also published here.




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