Finding infinity: seven ways to focus on the night stars

Getting sharp, pin-point stars for a starry sky or the Milky Way may be the hardest part of night photography. However, I’ll try and make it methodical and easy. I’ll discuss seven methods.

 

Focusing on a distant object during the day

The easiest way to do this is to go out some time when there’s some daylight and focus on something extremely far away. Choose the mountains or the clouds.  It may be right at the lens’ infinity marking.  Or slightly to the right.  Or slightly to the left.  Regardless, mark that setting if you can with a grease pen. Or better yet, tape the focus ring down with gaffer’s tape so it will not budge. Now you’re ready for the night.

 

Focusing on a distant object at night

Some people will have a friend stand at least fifty feet away and hold up a light. Then they will adjust their focus manually until the light looks like a pinpoint. If you don’t have a friend nearby, lean a flashlight against a tree or rock. This is far enough away that your lens should perceive this as infinity. This method also works well.

 

Focusing on the moon

Photographing while the moon is out? You’ll get less stars, but on the other hand, the moon may beautifully illuminate the foreground.  Aim your camera so the moon appears in the center. Use auto focus. The moon should be plenty bright enough for your auto-focus to work. If not, go ahead and switch to manual focus and then focus on the moon. You may do this via Live View or looking through the viewfinder.

 

Adjusting using your LED

Set it to where you believe infinity is based on the markings on your lens. Zoom in a star using your LED. Then adjust your lens accordingly. This may take a while.  This is easier with some cameras than others. Be patient.  You want the stars to be as sharp as possible. This method can be more accurate than the first two methods, but takes more patience.

 

Made from 20 light frames (captured with a NIKON CORPORATION camera) by Starry Landscape Stacker 1.6.1. Algorithm: Median

 

Adjusting using Live View

This is similar to the above method, but is generally easier to see than zooming in with an LED.  Zoom in to a star using Live View. Adjust the focus of your lens manually until it looks very sharp. This should go rather quickly, and is considerably faster and easier than using your LED. If this option is available to you, I would recommend doing this first. It is easy and arguably the most accurate of the ones listed.

 

Lens filters that help you focus

These are filters that use diffraction methods to nail focus. if you want to know more, search Bahtinov filters,  SharpStar2, or similar variations on this theme.

 

Using a lens with true infinity

Some manual lens have a hard stop for infinity. For many of these lens, this may actually represent their true infinity. You won’t know until you test. Other lenses, such as the Irix 15mm f/2.4, have a detent for true infinity. This make adjusting for infinity incredibly simple and easy.

 

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MY WEBSITE:
Head on over to the Ken Lee Photography website to purchase books or look at night photography and long exposure photos.  My latest book, “Abandoned Southern California: The Slowing of Time” is available there and Amazon, Barnes and Noble, Target, Booktopia, Books A Million, IBS, and Aladin. If you enjoy the book, please leave a nice review.

SOCIAL MEDIA:
Ken Lee Photography Facebook Page (poke your head in, say hi, and “like” the page if you would, uh, like)
Instagram

PODCAST:
Behind the Shot video podcast – interview February 2020

VIDEO INTERVIEW:
Conversation about night photography and my book with Lance Keimig of National Park At Night

ARTICLES:
A Photographer Captures Haunting Nighttime Images of Abandoned Buildings, Planes, and Cars in the American Southwest – Business Insider by Erin McDowell
A Photographer Explores Southern California’s Desert Ruins – Los Angeles Magazine article by Chris Nichols

 

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Featured Photo: Rock and Tree

Joshua Tree is otherworldly, and sometimes looks to me like a planet Captain Kirk and Spock might have beamed down on.  But I think this is rather captivating even by Joshua Tree standards. I shot this with a fairly small aperture to make certain both the narrow balancing rock and the lone tree, which is considerably closer to the camera, were both in focus.

Yes, this is another photo from my 28 April 2012 photographic trip to the desert, a 24-hour excursion for taking photos during both the day and night. This month we’ll be featuring many of these photos, and on June 1st, will discuss in detail the process of how the star trails photo from a couple of posts ago was created.
Equipment:  Nikon D90, 18-200mm VR Nikkor lens

VISIT ME, VISIT ME!
You can see more of these photos here  on my Ken Lee Photography Facebook Page (poke your head in, say hi, and “like” the page if you would, uh, like).

And you can go to the Ken Lee Photography website, which has more photos from Ken Lee.  Thank you very much for visiting!

How Do You Take Photos of the Stars (but not a star trails photo?)

So I’ve gotten a lot of positive response to the star trails article, although curiously not in the Comments Section!!  Aside from asking about details about star trails photography, the most common question has been:  “how do you take photos of the stars”?

Title: Trinity Stars
Info: Nikon D7000, Tokina 11-16mm f/2.8 lens, Dorcy LED flashlight for “light painting” the rocks and the trees. 30 second exposure, f/4, ISO 500.
Photographer: Ken Lee
Location: Joshua Tree National Park, CA USA

FOCUSING AT NIGHT:  First, we’ll discuss focusing.  That’s the hardest part of night photography, so I’ll start off with this and scare off the timid.  😀

There’s going to be some variability depending on the camera and lens you use, so it’s not just a simple matter of saying, “Do this, then do that.”

I focus on the stars by setting my lens to “infinity”.  But wait….it may not be quite as easy as that.  Why?  Because not all  lens indicate “infinity” in the same manner.  The easiest way to do this is to go out some time when there’s some daylight and focus on something extremely far away, like some mountains or the clouds or something and see where your lens perceives “infinity” to be.  It may be right at the lens’ Infinity marking.  Or slightly to the right.  Or slightly to the left.  With one photographer’s Pentax lens, it was between 11-14 ft.!!!  Now, I’m rather lucky because the “infinity” setting on my Tokina 11-16mm is right in the MIDDLE of the infinity symbol.  Beautiful.  Regardless of where it is, mark that setting.

Title: The Guardian of Forever
Info: Nikon D7000, Tokina 11-16mm f/2.8 lens, Feisol tripod. Exposure time 25 seconds at f/8, ISO 200. Light painted with flashlight and red headlamp. That is the moon peaking through the middle of the arch!
Photographer: Ken Lee
Location: Arch Rock, Joshua Tree National Park, California, USA.

If you are shooting at night and haven’t tested for infinity yet, try and focus on the shots as best you can, setting it to where you believe infinity is based on the markings on your lens or, if you can, manually..  Then take test photos of the stars  and view ’em in your LED, zooming in on the stars.  Then adjust your lens accordingly, zeroing in on where the stars look the sharpest.  This may take a while.  Be patient.  You want the stars to be as sharp as possible.  It looks great.  After the first time you do this, it gets much faster and easier. Using a flashlight, or better yet, a small headlamp with red light so you don’t constantly zap your eyeballs with white light, is the easiest way to view your lens and camera settings.

When you find your focus, switch your lens and camera off “auto focus” and on to “manual” so it won’t get moved again.  This is your infinity focus that you’re going to use from now on.  Some people use gaffer’s tape or blue painters’ tape to hold the lens in place, a good idea I picked up from Dennis Mammana, a night photographer.

If you can nail focusing at night, everything else is comparatively easy.

EXPOSURE:  Since you want the stars to be pinpoints, you need a relatively short exposure…at least, by night sky photography standards.  And that means keeping it under 20-30 seconds, depending on what lens you have.  A wide angle lens tends to show trails less than a telephoto lens.  I’ll let you figure out why.  😀  Much longer than 30 seconds, and your photo will likely show your stars as a very short line and not a pinpoint of light.

Use a lens at a fairly wide aperture, something like f/2.8 is nice.  Something that is good and wide to let as much light in as possible since stars don’t give off all that much light.  You can set it to smaller apertures but then you won’t let in as much light, and you’ll have to kick up your ISO.

Title: Hidden Valley Nights
Geek Stuff: Nikon D90 with Tokina 11-16mm f/2.8 lens, Feisol tripod; 30-second exposure, f/2.8, ISO 800. 26 March 2012. Everything is lit solely by moonlight.
Photographer: Ken Lee
Location: Hidden Valley, Joshua Tree National Park, California, USA

Now, set your camera to the lowest ISO you can get away with while still having your stars show nice and bright.  Why the lowest ISO you can get away with?  Because higher ISOs, while more light sensitive, also introduces more noise.

On my camera/lens combination, my widest aperture was f/2.8, good and wide, and with that wide of an aperture, I could get away with an ISO as low as ISO 800 for a 30-second exposure, which is quite good.  ISO 800 on a relatively modern digital camera doesn’t introduce too much noise.  If I wanted, I could have probably used a higher ISO such as 1600 if I wanted a 20-second exposure, which would have had less star trails, but I was satisfied with the lack of star trails on my 30-second exposure and chose to keep those settings.

If your image is too dark, make it brighter.  Widen the aperture.  Kick up the ISO. Or if you must, lengthen the exposure time, but remember that past 30 seconds, the stars may start to appear as very short lines, although I’ve seen people do exposures of 40 seconds that still looked like pinpoints because the used an extremely wide angle lens or just managed to get away with it somehow.

If your image is too bright, make it darker.  That’s easy.  Lower the ISO.  Make your aperture smaller.

Exposure is fairly simple.  Darken or brighten using the same tools you do during the day. Focusing is a greater challenge, but if you’re patient and take some test shots, you’ll nail those too.