Vari Focal
Bi-Voices Against Vari-focals?
Does anyone use variable focal lens? What are the pros and cons compared with bifocals?
Bifocal (on line) have existed since the days of Ben Franklin (he invented!) And are becoming obsolete. Lined bifocal only give a correction of two distances, far away (beyond 20 feet or less) and near (18 inches and more) and because they only have two corrections in the lens that are easier for most people to adapt. They still need an adjustment period but often happens much sooner than for most patients. What about objects in the middle? Lined bifocal offer nothing to the screen of a computer, or even see objects on the platform at the grocery store. To see a label on the shelf at the store, people tend to have either a few steps back to see through the top of the lens, or tilt the head back and walks to the label to use the reading portion of the lens. Also with the bifocal, has a big jump in prescription. As your looking down through the lens, its going very far, to upclose … very abruptly. Not smooth and gradual. That line can also take a lot of glare, because you can feel that line on the surface of the lens. Its low surface and causes a small advantage, that when light is captured just right, you get a glance of it. And not to mention the fact that most people * * I think the line is bad and usually are not ready to let the world know that they are growing. So from a standpoint of vanity, bifocals are not the best for people who are in denial about their age! LOL varifocal lenses, also known as progressive lenses or bifocals, no line is a much more versatile. You get the same recipe near and far, but also give you a prescription for everything in between and therefore, are closer natural vision. The human eye has the intention to see clearly at all distances, not just near the Progress and beyond 20 feet (Varifocal) achieve this objective lenses. So now, you have a goal that can drive, read, use your computer, shaved, and just about anything. The prescription runs in a channel on the target (usually your og mushroom-shaped) and to use them properly, all you need is a slight head tilt. To see the device, may have to tilt your head slightly down (I'm talking about a few degrees. You should not have to bury your chin on your chest to see clearly to drive. If you find that you must do this, it means that the lenses have been measured too high) After seeing things in other distances, you have to tilt your head a few degrees accordingly, depending on how far it is. Again, it should only be a few degrees. And the clearest part of the lens is always when looking through that channel I mentioned … which means to point the nose in what you're looking at to see things clearly. On either side of the lens there is some distortion. There are lenses available that have minimal distortion and they are better than a standard lens. Less distortion equals easier to adapt to the lenses, that is another story all together. The reading portion of the lens works much like the old bifocals, just drop your eyes and reading area should come in. Because with all the requirements of progressive lenses, and because there is some way to use the lens for a person to succeed, they have more time for most * People used to. I think that some patients are slow to grasp the concept of having to tilt the head, and point the nose in what you see. It is a gift for She and most patients make the adjustment within a week or two. Not that occasionally too much time and returned to our office several times because are struggling to adapt. Most patients receiving progressive lenses (varifocals, whatever …) very well with them and are happy with their convienance and versatility. You get an occasional person who can not use them correctly. And in my opinion, most of those people who say they can not use or are not properly using or not using enough. People expect to be able to pick up and see right away without any adjustment period necessary. In order to adapt to lenses, you must pick up and use them as much as possible, not only for an hour here and there. You need to build a tolerance and retrain the eyes and head in how use and can not do that in an hour here and there. Take some time and patience … and those are things that a lot of users without success progressives are reluctant to invest in their glasses. Progressive lenses are not for everyone and there are certain circumstances where a person would say that maybe are not for them. A patient who is 70 + that is worn bifcoals line for 20 years now, usually (not always) have a hard time to get used to them. People who need large areas of reading, as Architechs using planes usually need a larger reading area that offers a progressive lens. Not always, but generally * *. Furthermore, roofers and workers Construction … up tall buildings and scaffolding lenses … Progressive may be difficult for them. But in general, progressive lenses probably work well for 90% of patients. They are a bit more expensive, but offer much more for the patient. It's like having three pairs of glasses, all in one, one for distance, one for reading, and one for the team. So when you feel that way, really are not that expensive. The difference is that you have a pair of glasses that makes the work of three so there are only a pair of carry and keep track of, which is very good for most people who are carrying around multiple partners, since they have a couple that does it all. I hope this helps!
Alinking 40M VariFocal IR IP Camera ALC 9652 Outdoor
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Panasonic Ps-poc244l5dw Camera Kit W/ Vari-focal Lens (pspoc244l5dw) $338.31 |
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Iris Vari-Focal Dome Camera – NTSC Model# IM-DND-80 $799.88 |
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DOME 1/3″ SONY CCD COLOR IR VARI-FOCAL VANDAL CAMERA $65.89 |
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Panasonic PS-POC244L5DW-Camera Kit w/ Vari-focal Lens $338.58 |
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SONY 600TVL CCD Vari-Focal 4-9MM IR Weatherproof Camera $69.95 |
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SONY 600TVL CCD Vari-Focal 4-9MM IR Weatherproof Camera $69.95 |
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Hi-Res 6-60mm Vari-Focal Lens 80m 600tvl Long IR Range CCTV Outdoor Camera, Secu $141.75 |
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GANZ VARI-FOCAL DOME CAMERA $50.00 |
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Panasonic security camera kit with vari-focal lens- Col $365.39 |
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INDOOR VARI-FOCAL B&W DOME CCTV video CAMERA MD4168V 12VDC Zoom 600TVL $35.39 |
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IR Vari-focal CCD Dome Integrated Security Camera 1M6 $111.99 |
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Color CCD Vari-Focal Weatherproof 80′IR Security Camera $79.80 |
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4 CCTV Color CCD Vari-Focal Weatherproof 80′IR Cameras $266.00 |
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Philips 1/3″ Vari-Focal Lens DC Iris 1/3″ 2.8mm-10mm F/1.4 Z31 $23.99 |
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Used Philips 1/3″ Vari-Focal Lens DC Iris 3.5-8mm, F1.4 4pin Ser. Nr. 0242 Y46 $15.99 |
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Philips 1/3″ Vari-Focal Lens DC Iris 3.5-8mm, F1.4 4pin K36 $25.60 |
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Lot 8 3.5-8mm CCTV camera Lens CS Man-Iris Vari-Focal $99.00 |
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Lot 16 3.5-8mm CCTV camera Lens CS Man-Iris Vari-Focal $199.00 |
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Cosmicar Pentax 3.5-8mm Auto-Iris Vari-Focal Lenses (5) $9.99 |
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650TVL 1/3 Sony CCD 4~9mm Vari-Focal Len Vandalproof Dome Indoor Security Camera $95.00 |
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6 – 15 MM CCTV Lens CS manual-Iris Vari-Focal w/Lock $14.95 |
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New 5.5-33MM CCTV Camera Lens CS Auto-Iris Vari-Focal $45.90 |
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9-22MM CCTV Camera Lens auto-Iris Vari-Focal board lens $57.99 |
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Clover Day Night Vision Vari-Focal LED Dome Surveillance Security Camera 100′ IR $199.95 |
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SONY 600TVL CCD Vari-Focal 4-9MM IR Weatherproof Camera $69.95 |
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540TVL 1/3 Sharp CCD Vari-Focal 4~9mm manual Len IR Dome Outdoor Security Camera $75.90 |
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Sony 1/3″ CCD Color Vandal Proof IR Vari-Focal Dome $139.99 |
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560TVL Sony CCD Dome Outdoor CCTV Security Camera Vari-Focal 4~9mm 0 Lux 82ft $79.95 |
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Sony Ex-View Vandal-Proof Vari-focal Day/Night Dome Cam $199.99 |
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600TVL SONY CCD CCTV IR Dome Indoor Security Camera Vari-Focal 3.5~8mm Len 36 IR $92.00 |
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520TVL 1/3″ Sony CCD Dome Outdoor Security Camera Vari-Focal 4~9mm 30 IR LED $79.95 |
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650TVL 1/3 Sony CCD 4~9mm Vari-Focal Len 36 IR LED Dome Indoor Security Camera $95.00 |
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NEW Security Camera 5-100mm f/1.8 1/3″ CCD CCTV Auto Iris Vari Focal Lens $12.99 |
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700TVL Sony CCD IR CCTV Dome Outdoor Surveillance Camera Vari-Focal 4~9mm Len $115.00 |
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Adjustable 3.5~8mm Auto-Iris CCTV SECURITY CAMERA Vari-focal Lens, CS mount $25.00 |
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Adjustable 2.8~12mm Auto-Iris CCTV SECURITY CAMERA Vari-focal Lens, CS mount $39.95 |
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FUJINON WIDE 2.7~13.5mm Auto-Iris CCTV SECURITY CAMERA Vari-focal Lens, CS mount $55.00 |
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Indoor/Outdoor Vari-Focal Magnetic Dome Camera $578.00 |
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27X Zoom Auto Focus Sony CCD Camera 3.6-97.2mm Vari-focal Lens & Remote control $119.50 |
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Vari-Focal 6~60mm 1/3 Auto Iris CS mount DC Drive Lens for Security CCTV $48.89 |
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Vari-Focal 5~100mm 1/3 Auto Iris CS mount DC Drive Lens for Security CCTV $58.89 |
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CNB DBM-24VD Vari-Focal ULTRA High Resolution 600TVL ca $128.00 |
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Night Vision IR Vari-focal Security Camera AMG-R854BHH $145.00 |
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SONY 600TVL CCD Vari-Focal 4-9MM IR Weatherproof Camera $69.95 |
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520TVL 1/3″ SONY CCD Vari-Focal 8~20mm Outdoor Security Camera + Free AC Adapter $96.00 |
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COMPUTAR VARI FOCAL T3Z1014 CS 10-25MM F1.4 CCTV LENS $19.94 |
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Security Surveillance Outdoor Vari-focal W/Audio IR CCD Camera (CM-S23349SV-AD) $69.49 |
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DOME 1/3″ SONY CCD COLOR IR VARI-FOCAL VANDAL CAMERA $43.99 |
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Computar TG2Z3514FCS-2 CCTV Lens 3.5-8mm F1.4 Vari Focal $53.00 |
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Security Camera High Resolution Sony CCD Infrared w/ Vari-focal Lens $34.99 |
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PANASONIC PLZ27/5DN CS MOUNT VARI-FOCAL LENS W/ AUTO IRIS DC, 2.7-13.5mm $50.00 |
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420 TV Lines COLOR DOME IR VARI-FOCAL VANDAL CAMERA $57.99 |
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Computar , Vari focal Mini connector TG10Z0513FCS-2 $34.99 |
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NIB TOSHIBA FUJINON FUJIFILM VARI-FOCAL CTV LENS YV2.8X2.8LASA2L 2.8-8mm F0.95Â $29.99 |
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Vari-focal 100′ IR Dome Camera with Audio $79.99 |
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Vari-focal 420TV Line Sony CCD 65′ IR Indoor Night Vision CCTV Camera With Audio $74.75 |
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Capture CCTV SN-VPB4840 Vandal-Proof Vari-Focal Dome Camera $91.64 |
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AXIS M3204 NETWORK CAMERA DOME TAMPER-PROOF COLOR FIXED IRIS VARI-FOCAL 0337001 $561.07 |
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10 LED IR True D/N Vari-Focal 420TVL, SSM-742AII $151.36 |
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10 LED IR True D/N Vari-Focal 550TVL, SHM-755AII $171.35 |
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10 LED IR True D/N Vari-Focal 420TVL, SSM-742AII $157.49 |
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10 LED IR True D/N Vari-Focal 550TVL, SHM-755AII $194.82 |
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4Ch DVR & 4xIR Bullet Camera (2.9~10mm Vari-Focal) Package $695.20 |
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82-14330 Weather-Resistant Long-Range Vari-Focal Dual Lens Bullet Camera $338.87 |
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New DBM-20VDL CCTV Built-In Vari-Focal Lens 600TVL $115.00 |
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0.001 Lux Starlight 650TVL CCTV Board Camera Vari-focal Lens 3D-DNR D-WDR $66.00 |
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HAWK-I HAWK561VXIRCB Color IR Bullet Style, Vari-Focal 4 -9mm, High -Resolution, $99.99 |
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Panasonic WV-LZA61/2S Vari Focal Zoom Lens 3.8 mm – 8 mm F/1.4-1.8 $59.99 |
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CCTV CCD Surveillance Cam Vari-Focal IR Security Camera $63.99 |
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Vari-Focal 3.5mm-8mm CS Security Camera Lens, Manual $29.00 |
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Vari-Focal AUTO-IRIS 6mm-15mm, CS Security Camera Lens $49.95 |
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Vari-Focal AUTO-IRIS 5.0mm-100mm Extreme Zoom lens cctv $94.00 |
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V2262D – Outdoor Vandal Resistant Vari-Focal Dome Camera $150.75 |
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Vari-Focal AUTO-IRIS 2.8mm-12mm,CS Security Camera Lens $59.00 |
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V3363D – Kaltech High Resolution Vari-Focal Vandal Proof Dome Camera $174.25 |
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Vari-Focal AUTO-IRIS 3.5mm-8mm,CS Security Camera Lens $44.00 |
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Vari-Focal AUTO-IRIS 6mm-60mm,CS Security Camera Lens $75.00 |
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LEN0660 1/3Vari-Focal Lens 6.0 – 60.0mm DC Driver lens $49.99 |
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LEN3580 1/3 Vari-Focal Lens 3.5 – 8.0MM DC Driver lens $25.99 |
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LEN2812 1/3 Vari-Focal 2.8 – 12.0MM lens DC Driver lens $39.99 |
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480 Vari Focal Metal Security CCTV Surveillance Camera $74.99 |
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NEW DVT Computar Vari Focal LCC-05Z LCC05Z 5-50mm F1.3 $175.00 |
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(4) 1/3″ SONY CCD Vari-Focal Surveillance CCTV Cameras $368.00 |
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IC REALTIME EL720: Indoor Vari-Focal Dome Camera $300.00 |
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4-9mm Vari-focal 65′ IR Indoor Dome Camera with Audio (CM-S22129BG-AD) $72.49 |
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650TVL, Korea Vari-focal D/N Dome Cam Sony SuperHad CCD $181.91 |
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High Resolution 650TVL Vari-focal Indoor Camera with 65′ IR (CM-S22719BG-AD) $99.99 |
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6- 60 mm 60MM CCTV Camera Lens manual Iris Vari-Focal NEW $44.99 |
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Sony CCD 540TVL Waterproof Outdoor IR Vari-focal Dome Camera 3.5-8mm Lens $94.99 |
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Mini Vandal Dome Vari-focal camera Sony 540 line 40m IR $134.20 |
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EFFIO-E 700TVL 2.8~12MM VARI-FOCAL LENS 1/3 SONY EXVIEW HADII CCD HD IR DOME $100.00 |
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VARI-FOCAL INFRARED HIGH RESOLUTION CAMERA suveilance Security sony CCD 0 lux IR $75.95 |
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Vari-Focal 1/3″ Sony CCD IR Vandalproof Weatherproof Security Camera with Audio $79.99 |
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1/3″ Sony CCD 420 TV Lines 4-9mm Vari-Focal Lens IR Security Camera with Audio $74.75 |
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COMPUTAR VARI FOCAL TV LENS TG2Z3514AFCS-2 $29.99 |
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13VD5-40 Pelco 1/3″ Format Vari-Focal Zoom, 5-40mm Auto Iris NEW $76.50 |
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(4) VARI-FOCAL 1/3″ SONY CCD SURVEILLANCE CCTV CAMERA $389.95 |
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Clover HDC560 OUTDOOR VARI-FOCAL, NIGHT VISION CAMERA $299.00 |
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IRIS VARI-FOCAL DOME CAMERA NTSC $775.00 |
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Nikon Vari focal View Finder 2.8cm 28mm Wide Angle Attachment rangefinder $899.99 |