night sky

Six Tips for Choosing Binoculars for Stargazing

2 minutes

Why Binoculars Are Good for Stargazing

When you think of astronomy, you naturally think of telescopes.  But did you know that binoculars are excellent for exploring the night sky?  Here are some of the reasons why.

  • They have a wide field of view
  • You can look with two eyes.
  • They are easy to access.
  • There is no need to set up a tripod and get your bearings.
  • They are especially good for children, because they can see something immediately and won’t get bored waiting for you to focus.
  • They produce right side up images.
  • They can be used for observing many other things during the daytime.

Here Are Six Tips for Choosing a Binocular

  1. Check the magnification and make sure it is at least 7X’s.  The highest for hand held binoculars is 10X’s, but that is hard to hold steady.  Anything above 10X’s will require a tripod.
  2. The aperture which is the diameter of the front lens, should be at least 40 mm.  You need at least this much to gather sufficient light at night to see your object in the sky.
  3. The “exit pupil” is a term I ran across when I was researching the Nikon 7294 Monarch ATB 8×42 Binocular.  It refers to the width of a beam of light as it leaves the eyepiece.  Your goal is to match the exit pupil to the size of your dark adapted eye.  If the exit pupil is larger than the dilated eye, you will lose light and objects will appear dimmer.  As you age, the dilation of your pupil becomes less.  If you are over forty, your dilated eye will be about 5 mm.
  4. The field of view is expressed as a certain number of feet at 1000 yards.  The lower the magnification, the wider the field of view will be.
  5. Prisms fold light internally and produce an image right side up.  Porro prisms are heavier and bulkier but produce a little more light than roof prisms.  Roof prisms, on the other hand, are lighter and more compact, but produce a little less light.  If you are planning on also using your binoculars for daytime viewing, I would recommend you consider the roof prism type.
  6. There are three types of focusing mechanisms in binoculars.
  • There is a central focusing knob that focuses both eyepieces at the same time.
  • There is another type of knob that sets the focus for both eyes, but then allows you to fine tune the focus of one of the eyepieces.
  • The third type allows you to focus both eyes individually.

Binoculars are an easy way to explore the night sky and now you know a few things to look for when choosing a pair of binoculars.  I have found the Nikon Monarch 8 X 42 ATB binoculars an excellent choice for day and night viewing.  Check out my Nikon Monarch Review.

Leave a Reply