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The Best Zoomable Binoculars of 2023 – Reviewed and Top Rated

After hours researching and comparing all models on the market, we find out the Best Zoomable Binoculars of 2023. Check our ranking below.

2,951 Reviews Scanned

SaleRank No. #1

Celestron – UpClose G2 10–30x50 Binocular – 10-30x Zoom Binoculars for Beginners – Multi-coated Optics for Bird Watching, Wildlife, Scenery and Hunting – Porro Prism – Includes Soft Carrying Case

LARGE 50MM OBJECTIVE LENSES: Larger objective lenses gather more light and produce brighter, more detailed images. These 50mm objectives bring in lots of light while remaining relatively lightweight, so you can observe with or without a tripod.
MULTI-COATED OPTICS: Anti-reflective lens coatings improve color and contrast while maximizing brightness.
DURABLE AND WATER-RESISTANT: A rubber-covered aluminum housing protects your binoculars from damage and provides a secure gripping surface. The water-resistant exterior and stands up to tough conditions and unexpected rainy weather.
ACCESSORIES INCLUDED: UpClose G2 binoculars come complete with a soft carrying case and a built-in neck strap.
UNBEATABLE WARRANTY & CUSTOMER SUPPORT: Buy with confidence from Celestron, a leading optics brand in California since 1960. Your purchase includes a Celestron Limited Lifetime US Warranty & US-based expert tech support.

SaleRank No. #2

Nikon 8252 Aculon A211 10-22x50 Zoom Binocular (Black)

Aculon A211 10 22x50 zoom binoculars are designed to be as light as possible along with excellent ergonomics
Easy to reach fingertip zoom control knob allows for quick and easy adjustment of the binoculars magnification from 10 up to 22 power. Interpapillary distance adjustment (millimeter) - 56-72
Turn and slide rubber eyecups allow for comfortable viewing during extended periods of use; Minimum focus distance 49.2 feet / 15 meter
Multicoated eco glass lenses deliver a bright and clear image in most lighting conditions; Field of view 1000 meter (meter/feet) 66/199; Apparent field of view (°) 36.7; Real field of view (°) 3.8
A durable rubber armored coating ensures a non slip grip, even in wet conditions; Exit pupil is 2.3 - 5 millimeter

Rank No. #3

BARSKA unisex-adult 10-30x50 Zoom Gladiator Binocular Black/Black, 21.1 x 7.9 x 24.1

Powerful zoom with different magnifications ideal for all outdoor activities and sporting events
Fully coated optics for crisp and sharp images with ruby lens to minimize glare
Large objective lens to maximize light transmission
Ergonomic design with shock-absorbing rubber armor
Includes carrying case and neckstrap

Rank No. #4

Nikon Aculon A211 10-22x50 Porro Prism Zoom Binoculars (Black) with Binocular Harness and Cleaning System Bundle (3 Items)

Bundle Includes: Nikon Aculon A211 10-22x50 Porro Prism Zoom Binoculars (Black), Focus Camera Binocular Harness and Nikon Lenspen Cleaning System
High-Quality Images: Featuring BaK4 Porro prism systems, Aculon A211 binoculars deliver high-quality images under a multitude of lighting conditions
Multicoated Eco-Glass Lenses: The Nikon Aculon A211 Binoculars are designed to deliver bright and clear images in most lighting conditions. It uses multicoated lenses that enhance the image brightness
Smooth Central Focus Knob: In addition to the Aculon A211’s comfortable and ergonomic design, it comes with a central focus knob that allows fast and smooth focusing for quick viewing
Durable Rubber-Armored Coating: The Aculon A211 10-22x50 Zoom Binoculars are built to sustain harsh weather conditions. As an added convenience, it features a durable rubber-armored coating for a non-slip grip surface

SaleRank No. #5

Celestron – SkyMaster 15-35x70 Zoom Binocular – 15 to 35x70mm Zoom Eyepiece – Multi-Coated BaK4 Optics for Outdoor and Astronomy Viewing – Tripod Adaptable – Includes Soft Carrying Case

POWERFUL 15-35X ZOOM BINOCULARS: These versatile binoculars can provide you with a wider view of the scene at 15x magnification or zoom in to an astonishing 35x power for an immersive view of the action.
LARGE 70MM OBJECTIVE LENSES: Larger objective lenses gather more light and produce brighter, more detailed images. The SkyMaster is a favorite among those who view in dim conditions near dawn and dusk or at night for astronomy.
BRIGHT, SHARP VIEWS WITH BaK-4 PRISMS: Prisms constructed of BaK-4 glass maximize light throughput to your eye so you see brighter, more detailed images.
DURABLE AND WATER-RESISTANT: A rubber-armored housing protects your binoculars from damage and provides a secure gripping surface. The water-resistant exterior stands up to tough conditions and unexpected rainy weather.
TRIPOD ADAPTABLE: Stabilize your binocular for added comfort and shake-free views by mount your 60mm SkyMaster binoculars on any traditional photographic tripod.

Rank No. #6

10-30x50 Zoom Binoculars for Adults, High Powered Military Binoculars for Bird Watching Traveling Hunting Concerts with Large View,BAK4,FMC Lens,Clear Low Light Vision at Night

High Power Zoom Binoculars--Professional 10-30x50 zoom binoculars with a 50mm big eyepiece and 10-30X magnification let you focus on the target for excellent details from 235 feet or 1000 yards away. Our powerful binoculars provide a bright, sharp, and vibrant image with more true-to-life details, making them ideal for outdoor activities like hiking, driving, and wildlife and scenic viewing. It works well for large-scale theatre productions, concerts, football games, etc.
HD & High-Contrast Images--The BAK-4 prisms and FMC multi-coated broadband green film in these bird watching binoculars produce crisp images, accomplish correct colour reproduction, and have a light transmittance of up to 99.5%. These features also help to prevent glare and protect our eyes. The zoom binoculars offer brighter eyesight in low-light situations like twilight but not for completely black nights. Clear low-light vision.
Durable, Waterproof & Comfortable Grip--Our powerful zoom binoculars have an unscented rubber armour coating, a non-slip fingerprint construction, and a safe and comfortable grip surface. O-ring sealed lenses with anti-fog coating keep moisture, dust, and other debris out of the binoculars' interior, making them waterproof, shock-resistant, long-lasting, and easy to hold.
Binoculars for Adults and Children--The eye distance of the ridge-designed binoculars can be adjusted to fit most adults and children's eyes, depending on their size. Your fingers can easily concentrate from 10X to 30X using the smooth zoom joystick, meeting all of your observational demands. Eyecups that can be adjusted up and down allow for ideal vision with or without glasses. The binoculars' folding feature makes them simple to focus for a crisp image and simple to use.
Widely Used & 100% Warranty--Zoom binoculars suitable for bird watching, hunting, animal viewing, sailing, travel, sports games, concerts, opera, stargazing, sightseeing and astronomical observation. If you have any questions, this high-quality binoculars also come with a 10-year warranty and 24-hour customer service, please contact us, we are committed to customer satisfaction.

Rank No. #7

Zoom Binoculars for Adults,10-24x50 Binoculars with Smartphone Adapter, Compact Waterproof Binoculars for Bird Watching Hunting Travel Football Games Stargazing with Carrying Case and Strap

Rank No. #8

Coleman 15-50x28 Compact Zoom Binoculars, Silver (CZ155028)

Compact & lightweight with continuous one-touch zoom and a magnification range of 15x to 50x
Fully coated high Definition objective lenses
Field of view: 2.0 Degree.9 Degree (105ft.-47ft./1000 yds.)
Porro prism optical design provides sharp resolution, bright and clear images
Fold down/up Rubber eyecups for use by eyeglass wearers

Rank No. #9

10-24X50 Zoom Binoculars for Adult，HD Professional/Waterproof Binoculars for Bird Watching Travel Hunting Concerts-BAK4 Prism FMC Lens-with Case and Strap

[Professional Zoom Binoculars] Professional 10-24x50 zoom binoculars, features 10-24X magnification and 50mm large eyepiece,allows you to focus on the target for great details from 1000 yards away.Our binoculars for adults offers a clear, sharp and vivid image with more true-to-life details,perfect for outdoor activities,such as climbing,hiking,driving,and watching wildlife and scenery.It’s also great for large stage play,concert, football game,etc.
[HD & High-Contrast Images] This binoculars for bird watching comes with BAK-4 prism and FMC muti-coated broadband green film for sharp images, which can minimize the loss of light due to reflection, thereby ensuring brighter and higher-contrast images, realizing a real color reproduction and providing light transmittance up to 99.5%.
[Binoculars for Adults & Kids] Compact binoculars with adjustable eye widths fit most adults and children. The smooth focus knob makes it easy to focus from 10X to 24X by finger. Smooth magnification adjustment for your various observation needs. Adjustable eye-cups can be twisted up and down for perfect viewing with or without eyeglasses.The folding function makes the binoculars easy to focus to obtain a clear image,it’s very easy to operate even by kids
[100% Waterproof & Moisture-Proof] This binoculars for adults adopts non-slip rubber armor and leather,makes it waterproof, shock-resistance,dural and comfortable in hand. O-ring sealed optics with fog proof coating, ensures it prevent moisture, dust and debris from getting inside the binoculars.This light weight binoculars also comes with carrying case for for easy carrying and storage, as well as protecting the binoculars for bird watching from collision
[10-Year Warranty]Our 10-24x50 professional binoculars for adults are made under strict quality control system for crisp and clear viewing experience.This high quality binoculars also comes with 10-year warranty and 24 hours customer service,if you have any questions,please contact us, We are committed to customer satisfaction.

SaleRank No. #10

Nikon Sportstar Zoom 8-24x25 Black

The Sportstar Zoom is perfect for multiple uses such as wildlife viewing, sports events and racing.
Multiple layers of anti-reflective compounds on all optical components offer the brightness and resolution needed for a wide range of conditions.
The Sportstar Zoom binocular provides excellent ergonomics, strength, and ruggedness in a package that is comfortable to carry

Rank No. #11

Hands-Free Binocular Glasses Portable Zoomable Fishing Glasses Fishing Binoculars,Binoculars Telescope for Outdoor Hunting Bird Watching Sightseeing Concerts

Focus system:Binocular single focusing.
Adjustable Focus of objective Lens, turning the right and left side can adjust the different amplification separately.
Magnification: 1-3 times Objective lens diameter: 28MM.High Material: ABS engineering plastics.
FISHING BINOCULARS:Portable fishing telescope, focal Length adjustment, rear lens switching, brown filter mode and white lens mode for daylight or night fishing. Suitable for watching the float of various models.
HANDS-FREE BINOCULARS GLASSES: High-definition optical glass lens, ABS lightweight material for the frame body, easy to carry. Can wear for a long time. The frame is hung in the ear to add a soft rubber sleeve, protect the ear, comfortable to wear.

SaleRank No. #12

Compact Binoculars, 10-180x100 High Magnification Long Range Wide Angle Zoom 50mm Full Optical Lens Professional Binoculars Telescope for Bird Watching

WIDE FIELD OF VIEW: Binoculars Designed with 24X power magnification, 22mm large wide‑angle eyepiece, 50mm large objective lens, and 1640ft/546.8yds large field of view are ideal for fast-moving subjects such as bird watching, driving, sports events. When you use this binoculars, the vision is broad and it is very clear for the gain of binoculars.
PROFESSIONAL POWERFUL BINOCULARS: Multilayer-coated aspherical lenses elements provide superior light transmission and minimal distortion, better image brightness, contrast and quality. The Bak-4 prism has a perfectly round exit pupil. Providing bright, clear and razor-sharp viewing.
DURABLE, SOLID, AND ANTI-SLIP GRIP: Binoculars adopted durable structure with Eco-friendly rubber sheath for shock-resistance and Anti-slip grip, making them not only in decent appearance of more wear-resistant but also perfect for outdoor activities such as climbing, hiking
EASY TO ADJUST: The centre-focus knob of this compact binoculars guarantee fast and high precision focusing. And it can also focus on the different distance with right eyepiece ring. So it is very convenient when you watch something for a long time.
PERFECT AFTER SALE SERVICE: Any questions,Please feel free contact us,we pay more attention to provide customers better items and shopping experience.

Rank No. #13

Gskyer 2550 Pirate Monocular Spyglass Telescope, Optical Binoculars, Wide Angle HD, Telescope for Adults Children, High Powered Professional Binoculars for Travel, Climbing, Watching, Games, Sports

High power and comfortable: 25x magnification and 50 mm large objectives lens, the best magnification for distance watching, which provides a more comfortable functionality and larger view. It provides large field of view (352ft/1,000Yds), extending your adventures to greater possibilities. The design of the monocular allows the wearer to get close to the eyepiece without interfering with the viewing experience and feel more comfortable.Both adults and children can use it.
FMC lens and BAK-4 prism: using FMC superior BAK4 green film prism and high quality precision design. The HD monocular telescope uses advanced BAK-4 optics prism and fully multi coated lens. The transmittance of the monocular lens is increased, improve the light transmission rate and resolution, giving the clear, crisp images.
Premium leather bag and case for carrying: the handheld mini telescope is in a premium leather cylinder bag, it is a telescopic designed for outdoor enthusiasts and easy to carry, allowing you to take the pirate telescope with you anywhere you go.
Ideal for outdoor enthusiasts: Monocular specially designed for outdoor enthusiasts, durable and waterproof. It is suitable for a variety of outdoor sports: bird watching, hunting, hiking trips, observing animals, camping, travelling, water sports, ball games, watching scenery, concert, outdoor exploration and other activities. Give you an amazing visual experience!
Perfect gift for lovers and kids: this handheld telescope is a unique gifting option for kids on occasions like birthday, Thanksgiving, Christmas, friendship's day, Easter, engagements, weddings, anniversaries and more, it comes with a real premium leather bag, be an incredible collection and never missing any important or beautiful scenes.

Rank No. #14

Spotting Binoculars For Kids And Adults Handheld Foldable Brass Binoculars Zoomable Portable Binoculars For Cruise Travel Watching Game Hiking Hunting Binoculars 10x42 Compact And (B, One Size)

Bright And Clear: This Mini Telescope Uses BAK4 With Good Light Transmission. 25x Magnification And 30mm Lens With Resolution Give You Bright, Wide And Far Field Of View
Durable: The Main Components Of This Telescope Are High-quality Metal Construction And Shiny Brass Finish. It Will Not Be Used In Heavy Rain Or Soaked In Water.
Wide Application: This Compact Telescope Is Perfect For Watching Sporting Events, Close-up Bird Watching, Hiking, Traveling, Sightseeing And More. Eye.
Great Gift Idea: The Brass Binoculars Come With A Leatherette Bag, Allowing You To Take It With You And Never Miss Any Important Or Beautiful Scenes. Great As A To Fulfill 's Dream Of Exploring The World
Lightweight And Portable: This Pocket Monocular Will Be Your Ideal Travel Partner, The Foldable Eyepiece Is Very Small In Size And Weight For Easy Storage, And The Included Bag Is Convenient To Carry Around With One Finger.

Rank No. #15

Coleman 8-21x50 Full Size Zoom Binoculars, Black (CZ82150)

Continuous one-touch zoom with a magnification range of 8x to 21x
Fully coated high Index objective lenses
Field of view: 4.4 degree-2.4 Degree (233ft.-126ft./1000 yds.)
Porro prism optical design provides sharp resolution, bright and clear images
Fold down/up Rubber eyecups for use by eyeglass wearers

SaleRank No. #16

SkyGenius 10 x 50 Binoculars for Adults Powerful Full-Size, Clear Durable Binoculars for Bird Watching Sightseeing Wildlife Watching Traveling Stargazing with Low Light Night Vision

[Professional Powerful Binoculars] SkyGenius 10x50 Binoculars Designed with 10X power magnification, 50mm large objective lens, and 367ft/1000yds large field of view are ideal for fast-moving subjects such as bird watching, driving, sports events.
[Weak Light Vision with Quality Optics] Design of Aspherical lenses and multi-layer coating guarantee excellent light transmission and well improve image brightness, contrast, and quality. birding binoculars can be used at night, but not in complete darkness
[Durable, Solid, and Anti-slip Grip] Binoculars adopted durable structure with odorless rubber armor for shock-resistance and Anti-slip grip, making them not only in decent appearance of more wear-resistant but also perfect for outdoor activities such as climbing, hiking
[Easy to Focus] Corrective optical coating is great for color fidelity and minimizes distortion. Diopter System adjusting the imbalance vision of both eyes. The smooth and large center focus knob makes it simple to operate and easy to focus (Adaptable to a tripod). Note: Product list: 1 * Binocular, 1 * Bag, 1 * Strap, 1 * Cleaning cloth, 4 * lens caps, but not including tripod and adapter.
[Adjustable Eye Cups] The rubber covered eyepiece can be twisted up and down for different people adjusting a proper eye relief. The eyeglass wearers can adjust the eye relief through rising eye cups and feel more comfortable

Rank No. #17

10X HD Telescope Binoculars，1.5 Inch LCD TelescopeDigital Camera Telescope Zoomable Binoculars with Recording Function

HD digital telescope uses excellent all-optical system and HD digital recording function.
It has not only HD imaging but also HD video recording function, which gives you perfect visual experience.
Suitable for taking pictures and videos for outdoor sports, evidence investigation, concerts, nature observation, bird watching, etc.
Elegant, delicate, fashion, portable and easy to carry.
With a rechargeable built-in lithium battery and USB cable, it is easy and convenient to charge for the digital binoculars.

Rank No. #18

Pentax UP 8-16x21 Compact Zoom Binoculars (Green)

Fully-multi-coated optics assure maximum light transmission resulting in high quality viewing. Every surface of every element is fully coated minimizing internal glare and flare and giving a bright clear view.
Unique Uni-body design enhances durability by locking objective lenses in a single housing and synchronizing the eyepiece movement. This minimizes moving parts and assures these binoculars will function properly and clearly for years to come.
Aspherical lens elements, which are critical in compact binoculars, provide exceptional edge-to-edge sharpness. This assures that items on the edge of your field of view are just as sharp as those in the center.
The UP models are offered in unique, attractive color options that match your personal style.

Rank No. #19

10-30x50 High Powered Military Zoom Binoculars for Adults, Low Light Night Vision/Daily Waterproof/BAK7 Prism/FMC Lens HD Professional Binoculars for Bird Watching Hunting Concerts (10-30x50, Black)

🔭[OPTIMAL EYEPIECE LENS SIZE]: 22mm large eyepiece diameter, large field of view. The 22mm lens collects more light than the smaller eyepiece binoculars, provides a clearer and brighter field of view. In addition to the silicone protective cover and reinforced tempered material, the lens of this size is also easier to protect than the larger eyepiece binoculars and is not easy to damage.
🔭[50MM FMC OBJECTIVE, BAK7 PRISM, NIGHT VISION]: The low light night vision binoculars with bak7 prism, 55MM objective lens, and FMC Full Multi-Layer Coating glass lens. The lens has well controlled glare and ghosting. It is easy to see objects in shadow even in backlight or bright background.imaging more vivid colors without dark edges.It can be used at night, but not in complete darkness.
🔭[QUALITY OPTICS]: The easy focus high power binoculars comes with 10-30x zoom magnification, tripod anti-shake interface, bringing you 235ft/1000yds high definition and large view.Corrective optical coating are good for color fidelity and minimize distortion. Diopter System adjusting the imbalance vision of both eyes. The smooth and large center focus knob makes it simple to operate and easy to focus.
🔭[ NON-SLIP & WATER-PROOF & SHOCK-PROOF & DUST-PROOF & ANTI-FOG] Ergonomics, Metal structure with 1.76lb (800g) is more stable.anti-slip fingerprints structure with odorless rubber armor for that provides protection as well as a secure and comfortable gripping surface. O-ring sealed optics with fog-proof coating prevents moisture, dust and debris from getting inside the binoculars. Waterproof, but can not be used in a heavy rain for a long time or soaked in the water.
🔭[WIDE RANGE OF USES]: The adults night vision and day binoculars suitable for bird watching, hunting, animal watching, sailling, travel, sports games, concerts, opera, stargazing, sightseeing and astronomical viewing. Also perfect for outdoor activities such as climbing, hiking, travelling, camping, watching wildlife and scenery.[PACKAGE]: 1 x Black messenger bag, 4 x Lens protective cap, 1 x binocular harness strap, 1 x Binocularss Instructions, 1 x Lens cleaning cloth, 1 x Zoom Binocularss.

Rank No. #20

Adjustable 8-20 x 42 Zoom Binoculars - Clear BAK-4 Prism FMC Lens

Zoom Binoculars - Adjustable zoom binoculars with 8 to 20x magnification
HD Binocular: Uses Multi-coated optics and BA4K prism (light transmittance is 99.58%).
Compact Binoculars - 5 - 3.8°field angle, 17mm large eyepieces and 42mm large objectives lens. 87-61m/1000m (261-183ft 1,000Yds) large field of view.
Rugged rubber - Protect the binoculars and provide a secure grip
Enjoy Photographing: Zoom binoculars can be used with the smartphone mount, If need smartphone adapter mount, please search ASIN: B08KGDQ8BS.

Last update on 2023-08-01 / Affiliate links / Product Titles, Images, Descriptions from Amazon Product Advertising API

How Do You Buy The Best Zoomable Binoculars?

Do you get stressed out thinking about shopping for a great Zoomable Binoculars? Do doubts keep creeping into your mind? We understand, because we’ve already gone through the whole process of researching Zoomable Binoculars, which is why we have assembled a comprehensive list of the greatest Zoomable Binoculars available in the current market. We’ve also come up with a list of questions that you probably have yourself.

We’ve done the best we can with our thoughts and recommendations, but it’s still crucial that you do thorough research on your own for Zoomable Binoculars that you consider buying. Your questions might include the following:

Is it worth buying an Zoomable Binoculars?
What benefits are there with buying an Zoomable Binoculars?
What factors deserve consideration when shopping for an effective Zoomable Binoculars?
Why is it crucial to invest in any Zoomable Binoculars, much less the best one?
Which Zoomable Binoculars are good in the current market?
Where can you find information like this about Zoomable Binoculars?

We’re convinced that you likely have far more questions than just these regarding Zoomable Binoculars, and the only real way to satisfy your need for knowledge is to get information from as many reputable online sources as you possibly can.

Potential sources can include buying guides for Zoomable Binoculars, rating websites, word-of-mouth testimonials, online forums, and product reviews. Thorough and mindful research is crucial to making sure you get your hands on the best-possible Zoomable Binoculars. Make sure that you are only using trustworthy and credible websites and sources.

We provide an Zoomable Binoculars buying guide, and the information is totally objective and authentic. We employ both AI and big data in proofreading the collected information. How did we create this buying guide? We did it using a custom-created selection of algorithms that lets us manifest a top-10 list of the best available Zoomable Binoculars currently available on the market.

This technology we use to assemble our list depends on a variety of factors, including but not limited to the following:

Brand Value: Every brand of Zoomable Binoculars has a value all its own. Most brands offer some sort of unique selling proposition that’s supposed to bring something different to the table than their competitors.
Features: What bells and whistles matter for an Zoomable Binoculars?
Specifications: How powerful they are can be measured.
Product Value: This simply is how much bang for the buck you get from your Zoomable Binoculars.
Customer Ratings: Number ratings grade Zoomable Binoculars objectively.
Customer Reviews: Closely related to ratings, these paragraphs give you first-hand and detailed information from real-world users about their Zoomable Binoculars.
Product Quality: You don’t always get what you pay for with an Zoomable Binoculars, sometimes less, and sometimes more.
Product Reliability: How sturdy and durable an Zoomable Binoculars is should be an indication of how long it will work out for you.

We always remember that maintaining Zoomable Binoculars information to stay current is a top priority, which is why we are constantly updating our websites. Learn more about us using online sources.

If you think that anything we present here regarding Zoomable Binoculars is irrelevant, incorrect, misleading, or erroneous, then please let us know promptly! We’re here for you all the time. Contact us here. Or You can read more about us to see our vision.

FAQ:

Q: What’s the best magnification for binoculars?

A: 7x to 10x binoculars are best for hunting application. For long range shooting, such as varmint hunting, a 12x to 16x magnification is best. At larger magnification, you will need to use a tripod or to stabilize the binoculars, as the image will be very shaky if used in standing position.

Q: What is the magnification of binoculars?

A: A hand-held pair of binoculars typically has a magnification of 7 to 12. Higher magnifications are technically possible but require the binoculars to be mounted securely.

Q: What is magnification binoculars?

A: Binocular magnification is how much larger an object appears when viewed through binoculars compared to how large the same object would appear when viewed with the naked eye from the same distance. If binoculars have 8x magnification, for example, a bird will appear eight times larger through the binoculars than with plain eyesight.

Q: How does binocular magnification work?

A: Fundamentally how binoculars work and magnify a view is by using lenses that causes light to do something known as refraction: Through the vacuum of space, light travels in a straight line, but as it passes through different materials it changes speed. So as light passes through a thick medium like glass or water, it slows down.