Lens Tube
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 37mm DSLR Camera Lens Adapter Tube Converter Ring for Canon A75 A85 Silver $6.88 Time Remaining: 29d 8h 20m Buy It Now for only: $6.88 |
 Nikon F MICRO Nikkor 55mm f 35 NON AI lens M2 extension tube for F2 Nikkormat $79.95 (2 Bids) Time Remaining: 2h 47m |
 58mm Lens adapter tube for Canon Powershot G10 G11 camera for use with telephoto $14.94 Time Remaining: 31m |
 Lens Adaptor Tube for Panasonic Lumix DMC FZ150 DMC FZ100 Leica V LUX 3 V LUX 2 $9.99 Time Remaining: 9d 9h 53m Buy It Now for only: $9.99 |
 Mamiya 645 AF Auto Extension Tube Set NA401 NA402 NA403 EX+ AFD D $157.50 (4 Bids) Time Remaining: 3h 53m |
 52MM MACRO CLOSE UP LENS + TUBE FOR NIKON P5000 P5100 CAMERA ADAPTER $32.19 Time Remaining: 30m |
 For Canon DSLR SLR 600D 1100D 550D Macro Extension Tube Set+Lens Cleaning Pen $8.99 Time Remaining: 30d 3m Buy It Now for only: $8.99 |
 Canon FD 50 Extension Tube $26.49 Time Remaining: 1h 38m |
 TELEPHOTO + WIDE ANGLE + 3 FILTERS + TUBE FOR CANON G10 $49.99 Time Remaining: 2h 45m Buy It Now for only: $55.90 |
 CAMERA LENS ADAPTER TUBE P500+HOOD+UV+CAP 67mm for Nikon P510 Coolpix UV FILTER $39.90 Time Remaining: 20d 17h 1m Buy It Now for only: $39.90 |
 Adapter Tube+Lens Cap+Hood+UV Filter For 58mm Canon PowerShot G12 Camera $9.08 Time Remaining: 1h 8m Buy It Now for only: $9.99 |
 Macro Extension Tube Ring+Camera Lens Cleaning Pen For CANON EOS EF DSLR SLR $8.99 Time Remaining: 29d 20h 37m Buy It Now for only: $8.99 |
 Lens adapter for Panasonic Lumix DMW lA3 FZ18 FZ28 FZ38 camera tube $14.94 Time Remaining: 1h 46m |
 67MM CPL UV FLD LENS FILTER KIT + METAL ADAPTER TUBE FOR NIKON COOLPIX L110 $28.74 Time Remaining: 1h 46m |
 Nikon Micro Nikkor 55mm F 35 Compensating Lens +M2 tube Sharpest 55 ever made $124.95 Time Remaining: 27d 19h 3m Buy It Now for only: $124.95 |
 Telesar Extension Tube Set 13mm 21mm 31mm for Minolta MC lens mount $14.99 Time Remaining: 4h 30m Buy It Now for only: $29.99 |
 MINOLTA MD MACRO ROKKOR X 100mm f 35 Lens With 2 Tubes NICE $24.99 (1 Bid) Time Remaining: 3d 1h 52m |
 Camera C Mount Movie Lens Adapter Ring Tube to Fujifilm FX Mount X Pro1 Camera $14.95 Time Remaining: 20d 5h 18m Buy It Now for only: $14.95 |
 Leica 60mm Macro Elmarit Extension Tube $78.00 Time Remaining: 20h 42m |
 58mm Lens Adapter Tube Ring for Panasonic DMC FZ100 FZ150 FZ45 FZ40 AT FZ100 $11.98 Time Remaining: 9d 8h 27m Buy It Now for only: $11.98 |
 Vintage Nikon Nikkor Micro 55mm 35 Lens + PK 3 Tube $85.00 Time Remaining: 5d 2h 21m |
 SL 37mm 045X Wide Angle Lens + Adapter Tube For CANON A590 A570 IS $17.26 Time Remaining: 1h 52m Buy It Now for only: $18.99 |
 52mm Digital Camera Lens Adapter Tube Ring For KODAK P850 P712 $4.98 Time Remaining: 29d 9h 16m Buy It Now for only: $4.98 |
 FUJI PHOTO X FUJINON EBC 55mm 135 f35 MACRO DM LENS w EXTENSION TUBE SET $99.95 Time Remaining: 3d 3h 54m |
 Lot Two 2 Nikon Macro Extension tubes camera lens PK 3 PK 13 207158 $4.99 (1 Bid) Time Remaining: 1d 19h 43m |
 Macro Extension Tube Ring For SONY A900 A700 A500 A350 A300 Camera Lens $6.30 Time Remaining: 1d 2h 2m Buy It Now for only: $6.30 |
 Fuji Photo Film Co EBC FUJINON MACRO 135 f55mm LENS 1 1 tube M 42 pentax $98.33 (2 Bids) Time Remaining: 5d 2h 38m |
 Lens hood + UV CPL POLARIZED filter kit + camera adapter tube for Sony DSC HX1 $29.99 Time Remaining: 26d 17h 56m Buy It Now for only: $29.99 |
 Job Lot of Lenses Tele converters extension tubes and lens adapters Canon $48.97 (5 Bids) Time Remaining: 3d 14h 59m |
 VTG CANON LOT FD 35mm 128 RARE Macro 50mm Lens 135 FD 2 EXT TUBES CASES $13.95 (6 Bids) Time Remaining: 6d 31m |
 CAMERA LENS ADAPTER TUBE HX100V+UV 67mm for SONY DSC HX100V UV FILTER 67 mm $29.99 Time Remaining: 15d 18h 15m Buy It Now for only: $29.99 |
 LEICA M Lens To SONY NEX E mount MACRO TUBE HELICOID Adapter $26.00 (4 Bids) Time Remaining: 5d 16h 56m |
 LEICA M Lens To SONY NEX E mount MACRO TUBE HELICOID Adapter $84.99 Time Remaining: 17h 3m |
 Auto Focus AF Macro Extension Tube for Nikon D90 D60 D50 AF AF S DX FX Lens $69.79 Time Remaining: 2d 9h 54m Buy It Now for only: $69.79 |
 New Leica M LM lens to Fuji X Pro1 X1 Pro MACRO TUBE HELICOID Camera Adapter $129.99 Time Remaining: 1d 3h 46m |
 045x WC E75A WC E75 Super Wide Lens + UR E22 Tube for Nikon P7000 P7100 Camera $39.94 Time Remaining: 14d 5h 14m Buy It Now for only: $39.94 |
 UV HOOD WHITE BALANCE CAP LENS PEN FOR CANON G10 G11 G12 CAMERA ADAPTER TUBE $22.32 Time Remaining: 1d 31m |
 043x Wide Angle Lens w Adapter Tube for Canon PowerShot S5 IS $44.95 Time Remaining: 3d 2h 11m Buy It Now for only: $49.95 |
 58mm Lens Adapter Tube LA DC58K For Canon G12 G11 G10 $5.88 Time Remaining: 20d 5h 1m Buy It Now for only: $5.88 |
 Minolta MC ROKKOR QF 50mm f 35 MACRO w Case Ext Tube Reverse Mount $99.00 (1 Bid) Time Remaining: 17h 37m |
 52MM LENS TUBE ADAPTER FOR MINOLTA Z3 Z5 Z6 BLACK $6.89 Time Remaining: 1d 1h 46m |
 Hot 58mm 58 mm Lens Adapter Tube For Canon PowerShot S3 S5 $5.89 Time Remaining: 28d 12h 29m Buy It Now for only: $5.89 |
 LEICA SCREWMOUNT EXTENSION TUBES IN THE BOX $29.00 Time Remaining: 21h 52m |
 Bower FA DC67A Lens Adapter Ring Tube Canon PowerShot SX30 IS SX40 HS Camera $14.00 Time Remaining: 5d 22h 15m Buy It Now for only: $14.00 |
 52mm Lens Adapter Tube For Panasonic LUMIX DMC LX5 $5.45 Time Remaining: 1d 3h 40m |
 Thumb 52mm Lens Adapter Tube for Panasonic Lumix DMC LX5 DMC LX 5 Cam $5.45 Time Remaining: 1d 5h 42m |
 Nikon Macro Extension Tube Ring AI AF DSLR SLR Camera Lens D5000 D3000 D1 40 $8.99 Time Remaining: 23d 9h 4m Buy It Now for only: $8.99 |
 52MM MACRO CLOSE UP LENS FOR KODAK EASYSHARE P880 CAMERA ADAPTER TUBE $24.71 Time Remaining: 1d 2h 1m |
 52mm Macro Close Up lens + Tube for Nikon P6000 $22.99 Time Remaining: 1d 1h 46m |
 Camera C Mount Movie Lens Adapter Ring Tube to Fujifilm FX Mount X Pro1 Camera $14.99 Time Remaining: 21d 2h 54m Buy It Now for only: $14.99 |
 New MACRO SHOT EXTENSION Tube RING FOR CANON EOS EF lensEOS 50D 5D MK III 7D $3.25 (5 Bids) Time Remaining: 16h 10m |
 Z25 Telephoto + Wide Lens + UV Filter + Tube + Hoods + Cap For Canon G12 G11 G10 $49.50 Time Remaining: 13d 19h 45m Buy It Now for only: $49.50 |
 Thumb 52mm Lens Adapter Tube for Panasonic Lumix DMC LX5 DMC LX 5 Cam $5.55 Time Remaining: 7h 19m |
 SL 58mm 045X Wide Angle Lens + Adapter Tube For CANON Powershot G6 Camera $19.99 Time Remaining: 1d 5h 32m Buy It Now for only: $22.00 |
 Nikon Micro Nikkor 200mm F 4 IF Lens With PK 13 11 Tube For Film Or Digital $389.00 Time Remaining: 2d 18h 36m Buy It Now for only: $389.00 |
 TELEPHOTO + WIDE ANGLE + TUBE FOR NIKON P6000 $33.24 Time Remaining: 2d 4h 6m |
 PENTAX AUTO EXTENSION TUBE A 645 123 full set for Pentax 645 lens $189.00 Time Remaining: 4d 15h 39m |
 Lens Adapter Tube 4 Leica X1 X 1 to accept 49MM Filter $19.99 Time Remaining: 18d 5h 36m Buy It Now for only: $19.99 |
 SL 58mm 045X Wide Angle Lens + Adapter Tube For CANON Powershot G5 G3 Camera $19.99 Time Remaining: 2d 17h Buy It Now for only: $22.00 |
 49mm Spacer Ring For Lens Filter Adapter Extension Tube Metal Hood USA Fast Ship $14.99 Time Remaining: 24d 18h 36m Buy It Now for only: $14.99 |
 Canon FD 50mm 118 Lens with Canon Exten Tube FD 25 EXC Cond $40.00 Time Remaining: 2d 34m |
 LEICA Camera Ernst Leitz Wetzlar OUBIO Visoflex Camera Lens Extension Tube 16466 $39.99 Time Remaining: 4d 3h 48m Buy It Now for only: $59.99 |
 58mm Lens Adapter Tube for Canon Powershot A650 NEW $2.95 Time Remaining: 8d 16h 48m Buy It Now for only: $2.95 |
 Hardcase for Extension Tubes Close Up Lens or $2.99 Time Remaining: 3d 2h 51m |
 52mm Lens Adapter Tube Ring for Panasonic Lumix DMC LX5 $5.55 Time Remaining: 18h 22m |
 Macro Lens Extension Tubes Set For Canon 5D Mark II 7D 450D 550D 60D 500D 1000D $7.00 Time Remaining: 19d 2h 55m Buy It Now for only: $7.00 |
 BK 4Filter+Adapter Tube 58mm ND PL UV Lens For CANON Powershot PRO 1 Camera $17.26 Time Remaining: 1d 5h 34m Buy It Now for only: $18.99 |
 Auto Focus Macro Lens Extension Tube for CANON SLR DSLR $77.00 Time Remaining: 19d 9h 24m Buy It Now for only: $77.00 |
 Tiffin 52mm Close Up Lens Set w Canon G5 52mm Tube Adapter $59.95 Time Remaining: 1d 23h 52m |
 Selection of various Glass Lenses prisms Barlow tubes enlarging lens etc $1.56 Time Remaining: 4d 20h 49m |
 Hawks Leica M lens to Sony NEX E camera Marco tube helicoid adapter Ver 25 $192.80 Time Remaining: 18d 12h 14m Buy It Now for only: $192.80 |
 MINOLTA MANUAL LENS EXTENSION TUBES AND NO 1 MALE NO 2 FEMALE ADAPTER RINGS $35.00 Time Remaining: 2d 33m |
 52mm Lens Adapter Tube For Panasonic LUMIX DMC LX5 $6.75 Time Remaining: 22h 20m |
 52mm Lens Adapter Tube Ring For Panasonic LUMIX DMC LX5 $5.88 Time Remaining: 15d 8h 22m Buy It Now for only: $5.88 |
 LEICA Leitz Macro Adapter R 14256 Camera Lens Close Up Extension Tube Excellent $74.99 (1 Bid) Time Remaining: 4d 3h 48m |
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Alvin 37" Ice Tube, Triangular Transparent PVC Carry and Storage Tube, Transparent Blue - 3" I.D.
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DescriptionThe TL series has a unique triangular shape. Moisture and dust proof with an adjustable shoulder strap. 25" and 37" lengths with a 3" inside diameter. Lead and phthalate free UV protected PVC. |
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Lookout telescope Photo Mugs
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DescriptionThis is a hand-held achromatic telescope for use on board ship. It has a single draw tube, an extending shade for the objective lens to reduce glare when in use and a sliding eyepiece cover. The barrel is covered in leather, while all the other fittings are brass... |
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Naval telescope - inscription Photo Mugs
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DescriptionThis achromatic telescope has a tapering mahogany barrel with brass fittings, including a single draw tube, an objective lens cap and a pivoted eyepiece cover. It is typical of the sort of telescope used on board ship in the 19th century... |
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TerraLUX TLF-3C2AAEX LightStar220 3-Watt LED Aluminum Flashlight
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DescriptionLightStar 220 LED 2AA Flashlight EX Black Aluminum Body |
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DEWALT DCT410S1 12-Volt Max Inspection Camera Kit
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DescriptionWIRELESS SCREEN VIDEO & PHOTO CAPTURE 3X ZOOM MICRO SECURE DIGITAL CARD(TM) SLOT HOOK & MAGNET TOOLSUPC : 885911231312Shipping Dimensions : 20.70in X 14.20in X 5.00inEstimated Shipping Weight : 8.8536 |
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AR15 Combo Armorer's Wrench Tool
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DescriptionThis unique tool combines all of the necessary tools to eliminate the need of owning multiple wrench types. Use it for all of your M16 or .223 rifles and all of their variants. |
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Burt's Bees Beeswax Lip Balm Tube, .15-Ounce Tubes (Pack of 4)
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DescriptionThe original. The best. And still your favorite. Our must-have balms have been playing in purses and pockets since 1991. Beeswax conditions skin, while antioxidant Vitamin E moisturizes. A final hint of Peppermint Oil provides that one-of-a-kind refreshing tingle... |
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Replens Long-lasting Vaginal Moisturizer With Reusable Applicator, 35-gram Tubes (Pack of 2)
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Descriptionthe product is not eligible for priority shipping |
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Replens Long-lasting Vaginal Moisturizer With Reusable Applicator, 14 Applications
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DescriptionREPLENS VAG MOIST COMFORT TIP Size: 35 GM |
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SE Table Magnifier Lamp - 5X - Fluorescent Light (Black)
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DescriptionPowerful magnifying glass is ideal for precise work for those hard to see operations: dentistry, beauty salons, jewelry shops.- Gives excellent magnified lighting and hands free use for hobbies, close precision inspections, beauty salons, reading and general use for home or office. |
The Origins of the Contact Lens
Many people believe that the contact lens is a modern invention, but that's actually not the case. In fact, the origins of the contact lens extend as far back as the early sixteenth century. Even the modern form of contact lenses first emerged several decades ago. Since the very first conception of the principle behind contact lenses, these optical devices have undergone many different changes at the hands of several different inventors and eye care professionals. In fact, contacts have gone from cumbersome and uncomfortable devices made of glass to today's plastic lenses which offer a high level of comfort while providing sharp, clear vision for those with a wide variety of vision problems.
The history of the contact lens dates back to the early sixteenth century. More specifically, in 1508 Leonardo da Vinci came up with the general principle behind contact lenses. While he didn't actually create such a lens and wasn't necessarily concerned with correcting vision, da Vinci sketched and described a variety of ideas involving placing a lens directly on the eye in order to aid vision and alter the corneal power of the eye.
During the following century, in the 1630’s, France's René Descartes proposed the idea of a corneal contact lens. His idea involved the use of a liquid-filled glass tube placed directly against the cornea of the eye and shaped to provide corrected vision. In 1801, a scientist by the name of Thomas Young developed Descartes' idea by conducting experiments using a liquid-filled eyecup, the outer end of which contained a microscopic lens.
Also in the nineteenth century, British astronomer Sir John Herschel proposed ideas for correcting vision with a jelly-filled capsule and a corneal mould. These ideas were published in a footnote of the Encyclopedia Metropolitana in 1845. Although it's believed that Herschel never actually tested these ideas himself, they did provide the basis for experiments and inventions later on which would eventually lead to the creation of lenses shaped to fit the eye.
Just over 40 years after Herschel's ideas were published, in 1887, Germany's F.E. Muller created the first usable contact lens. Muller was a glassblower who made artificial eyes and while his contact lens could be seen through and could be tolerated for a few hours at a time, it was made of glass and was not very comfortable. Yet, just one year later, there were reports that both a German physician and a French optician were using contact lenses to correct vision problems caused by optical defects. In fact, the German physician, Adolph Eugen Fick, is sometimes credited with the invention of the contact lens. Fick develop Herschel's ideas and created scleral contact shells. He then experimented with fitting the lenses on rabbits and then on himself. However, as Fick's contact lenses were still made of glass, they were very uncomfortable and could only be worn for a couple of hours at a time.
Although glass contacts were so uncomfortable, they were the only type of contact lenses available until the 1930's. That was when polymethyl methacrylate was first developed. This new material led to the advent of the first lenses made of a combination of glass and plastic, which were introduced in 1936 by a New York optometrist by the name of William Feinbloom. Around 1950, an optometrist from Oregon developed the first corneal contact lens. Since corneal contacts were smaller than scleral lenses, they were more comfortable and could be worn for far longer periods of time.
These developments led to a vast increase in the use and appeal of contact lenses throughout the 1960's. Over the years, several significant advancements were made regarding the manufacture and the sophistication of contacts. One such advancement included the development of the first soft contact lens. These soft lenses were made available in some countries during the 1960's and were first launched in the United States in 1971.
Since that time, contact lenses have continued to improve in quality and comfort, and several new varieties of lenses have also been developed. For example, toric contact lenses were first approved for use in the United States in 1978, and the first rigid gas permeable lenses hit the market in 1979. Bifocal and tinted contact lenses became available during the 1980's while the 1990's saw the introduction of daily disposable and ultraviolet-absorbing contacts.
Clearly, the contact lens has a long history and numerous significant advancements have been made in recent decades. In fact, now people with astigmatism and many other types of eye diseases and vision problems can use contact lenses to see clearly and comfortably. Contacts are also becoming increasingly affordable and are available from a variety of discount retailers such as CoastalContacts.com. Considering the history of the contact lens, advancements in design and manufacturing will most likely continue to occur, making contact lenses even more of an excellent option for correcting all types of vision problems.
About the Author
Steven Myros is a freelance writer and contact lens user. He explains how contact lenses offer many great advantages that have more people starting to make the switch from glasses.
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