• Education
    • Higher Education
    • Scholarships & Grants
    • Online Learning
    • School Reforms
    • Research & Innovation
  • Lifestyle
    • Travel
    • Food & Drink
    • Fashion & Beauty
    • Home & Living
    • Relationships & Family
  • Technology & Startups
    • Software & Apps
    • Startup Success Stories
    • Startups & Innovations
    • Tech Regulations
    • Venture Capital
    • Artificial Intelligence
    • Cybersecurity
    • Emerging Technologies
    • Gadgets & Devices
    • Industry Analysis
  • About us
  • Contact
  • Advertise with Us
  • Privacy & Policy
Today Headline
  • Home
  • World News
    • Us & Canada
    • Europe
    • Asia
    • Africa
    • Middle East
  • Politics
    • Elections
    • Political Parties
    • Government Policies
    • International Relations
    • Legislative News
  • Business & Finance
    • Market Trends
    • Stock Market
    • Entrepreneurship
    • Corporate News
    • Economic Policies
  • Science & Environment
    • Space Exploration
    • Climate Change
    • Wildlife & Conservation
    • Environmental Policies
    • Medical Research
  • Health
    • Public Health
    • Mental Health
    • Medical Breakthroughs
    • Fitness & Nutrition
    • Pandemic Updates
  • Sports
    • Football
    • Basketball
    • Tennis
    • Olympics
    • Motorsport
  • Entertainment
    • Movies
    • Music
    • TV & Streaming
    • Celebrity News
    • Awards & Festivals
  • Crime & Justice
    • Court Cases
    • Cybercrime
    • Policing
    • Criminal Investigations
    • Legal Reforms
No Result
View All Result
  • Home
  • World News
    • Us & Canada
    • Europe
    • Asia
    • Africa
    • Middle East
  • Politics
    • Elections
    • Political Parties
    • Government Policies
    • International Relations
    • Legislative News
  • Business & Finance
    • Market Trends
    • Stock Market
    • Entrepreneurship
    • Corporate News
    • Economic Policies
  • Science & Environment
    • Space Exploration
    • Climate Change
    • Wildlife & Conservation
    • Environmental Policies
    • Medical Research
  • Health
    • Public Health
    • Mental Health
    • Medical Breakthroughs
    • Fitness & Nutrition
    • Pandemic Updates
  • Sports
    • Football
    • Basketball
    • Tennis
    • Olympics
    • Motorsport
  • Entertainment
    • Movies
    • Music
    • TV & Streaming
    • Celebrity News
    • Awards & Festivals
  • Crime & Justice
    • Court Cases
    • Cybercrime
    • Policing
    • Criminal Investigations
    • Legal Reforms
No Result
View All Result
Today Headline
No Result
View All Result
Home Science & Environment Space Exploration

What is the difference between a 2″ eyepiece and a 1¼” eyepiece?

March 17, 2025
in Space Exploration
Reading Time: 2 mins read
A A
0
Eyepiece showing field stop
3
SHARES
7
VIEWS
Share on FacebookShare on Twitter


From the March 2025 issue

A 2″ eyepiece delivers a wider true field of view than a 1¼” eyepiece of the same focal length.

The field stop is the visible ring that sits in front of an eyepiece’s field lens. It, along with the focal length of the telescope you’re using, will determine the amount of sky you can see. Credit: Alison Klesman

What is the benefit of a 2″ eyepiece compared to a 1¼” eyepiece?

Tom Nagy
North Ridgeville, Ohio

A 2″ eyepiece delivers a wider true field of view (the actual amount of sky visible) than a 1¼” eyepiece of the same focal length. Two factors determine the true field: the telescope’s focal length and the diameter of the eyepiece’s field stop. A field stop is a centered, circular opening in front of the eyepiece’s front (or field) lens. The bigger the field stop, the more sky you’ll see.

The only limit to field-stop size is the inside diameter of the eyepiece’s barrel. So, for example, a 20mm 2″ eyepiece will show more sky than a 20mm 1¼” eyepiece through the same telescope. What’s more, the magnification through both eyepieces will be the same.

Most observers prefer a wider field that doesn’t sacrifice higher magnification. This really helps skywatchers whose telescopes lack a motorized drive. A wider true field of view means you have to manually move your scope less often to follow objects as Earth rotates.

Michael E. Bakich
Associate Editor

This question and answer originally appeared in the July 2011 issue.

Tags: Ask AstroMagazineObserving
Previous Post

Eat grass-fed beef, help the planet? Research says not so simple

Next Post

Scientists Found The Silent ‘Scream’ of Human Skin For The First Time : ScienceAlert todayheadline

Related Posts

IC 342

Deep-Sky Dreams: Face-on spiral IC 342

May 22, 2025
3

NASA Astronaut to Answer Questions from Students in Washington State

May 22, 2025
5
Next Post
For The First Time, We've Heard The Slow, Silent Scream of Human Skin

Scientists Found The Silent 'Scream' of Human Skin For The First Time : ScienceAlert todayheadline

  • Trending
  • Comments
  • Latest
Family calls for change after B.C. nurse dies by suicide after attacks on the job

Family calls for change after B.C. nurse dies by suicide after attacks on the job

April 2, 2025
Pioneering 3D printing project shares successes

Product reduces TPH levels to non-hazardous status

November 27, 2024

Hospital Mergers Fail to Deliver Better Care or Lower Costs, Study Finds todayheadline

December 31, 2024

Police ID man who died after Corso Italia fight

December 23, 2024
Harris tells supporters 'never give up' and urges peaceful transfer of power

Harris tells supporters ‘never give up’ and urges peaceful transfer of power

0
Des Moines Man Accused Of Shooting Ex-Girlfriend's Mother

Des Moines Man Accused Of Shooting Ex-Girlfriend’s Mother

0

Trump ‘looks forward’ to White House meeting with Biden

0
Catholic voters were critical to Donald Trump’s blowout victory: ‘Harris snubbed us’

Catholic voters were critical to Donald Trump’s blowout victory: ‘Harris snubbed us’

0
Thousands of chicks found abandoned in USPS truck have been adopted

Thousands of chicks found abandoned in USPS truck have been adopted

May 22, 2025
DC Capital Jewish Museum shooting: Two awful truths about the murders

DC Capital Jewish Museum shooting: Two awful truths about the murders

May 22, 2025

China’s Origin Quantum upgrades its software for chip debugging

May 22, 2025

Phillips 66’s Los Angeles refinery layoffs to begin in December, sources say

May 22, 2025

Recent News

Thousands of chicks found abandoned in USPS truck have been adopted

Thousands of chicks found abandoned in USPS truck have been adopted

May 22, 2025
2
DC Capital Jewish Museum shooting: Two awful truths about the murders

DC Capital Jewish Museum shooting: Two awful truths about the murders

May 22, 2025
3

China’s Origin Quantum upgrades its software for chip debugging

May 22, 2025
4

Phillips 66’s Los Angeles refinery layoffs to begin in December, sources say

May 22, 2025
3

TodayHeadline is a dynamic news website dedicated to delivering up-to-date and comprehensive news coverage from around the globe.

Follow Us

Browse by Category

  • Africa
  • Asia
  • Basketball
  • Business & Finance
  • Climate Change
  • Crime & Justice
  • Economic Policies
  • Elections
  • Entertainment
  • Entrepreneurship
  • Environmental Policies
  • Europe
  • Football
  • Gadgets & Devices
  • Health
  • Medical Research
  • Mental Health
  • Middle East
  • Motorsport
  • Olympics
  • Politics
  • Public Health
  • Relationships & Family
  • Science & Environment
  • Software & Apps
  • Space Exploration
  • Sports
  • Stock Market
  • Technology & Startups
  • Tennis
  • Travel
  • Uncategorized
  • Us & Canada
  • Wildlife & Conservation
  • World News

Recent News

Thousands of chicks found abandoned in USPS truck have been adopted

Thousands of chicks found abandoned in USPS truck have been adopted

May 22, 2025
DC Capital Jewish Museum shooting: Two awful truths about the murders

DC Capital Jewish Museum shooting: Two awful truths about the murders

May 22, 2025
  • Education
  • Lifestyle
  • Technology & Startups
  • About us
  • Contact
  • Advertise with Us
  • Privacy & Policy

© 2024 Todayheadline.co

Welcome Back!

OR

Login to your account below

Forgotten Password?

Retrieve your password

Please enter your username or email address to reset your password.

Log In
No Result
View All Result
  • Business & Finance
  • Corporate News
  • Economic Policies
  • Entrepreneurship
  • Market Trends
  • Crime & Justice
  • Court Cases
  • Criminal Investigations
  • Cybercrime
  • Legal Reforms
  • Policing
  • Education
  • Higher Education
  • Online Learning
  • Entertainment
  • Awards & Festivals
  • Celebrity News
  • Movies
  • Music
  • Health
  • Fitness & Nutrition
  • Medical Breakthroughs
  • Mental Health
  • Pandemic Updates
  • Lifestyle
  • Fashion & Beauty
  • Food & Drink
  • Home & Living
  • Politics
  • Elections
  • Government Policies
  • International Relations
  • Legislative News
  • Political Parties
  • Africa
  • Asia
  • Europe
  • Middle East
  • Artificial Intelligence
  • Cybersecurity
  • Emerging Technologies
  • Gadgets & Devices
  • Industry Analysis
  • Basketball
  • Football
  • Motorsport
  • Olympics
  • Climate Change
  • Environmental Policies
  • Medical Research
  • Science & Environment
  • Space Exploration
  • Wildlife & Conservation
  • Sports
  • Tennis
  • Technology & Startups
  • Software & Apps
  • Startup Success Stories
  • Startups & Innovations
  • Tech Regulations
  • Venture Capital
  • Uncategorized
  • World News
  • Us & Canada
  • Public Health
  • Relationships & Family
  • Travel
  • Research & Innovation
  • Scholarships & Grants
  • School Reforms
  • Stock Market
  • TV & Streaming
  • Advertise with Us
  • Privacy & Policy
  • About us
  • Contact

© 2024 Todayheadline.co