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Our most complex organ in our body | by B℮n
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Our most complex organ in our body

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Eyes are the organs of vision. In a number of ways, the human eye works much like a digital camera: Light is focused primarily by the cornea — the clear front surface of the eye, which acts like a camera lens. The iris of the eye functions like the diaphragm of a camera, controlling the amount of light reaching the back of the eye by automatically adjusting the size of the pupil aperture. The eye's crystalline lens is located directly behind the pupil and further focuses light. Through a process called accommodation, this lens helps the eye automatically focus on near and approaching objects, like an autofocus camera lens. Light focused by the cornea and crystalline lens (and limited by the iris and pupil) then reaches the retina — the light-sensitive inner lining of the back of the eye. The retina acts like an electronic image sensor of a digital camera, converting optical images into electronic signals. The optic nerve then transmits these signals to the visual cortex — the part of the brain that controls our sense of sight.

 

Macro photo taken with a modified Canon EF35-80mm f/4-5.6 lens. Turn your old Kit Lens into a superb Macro lens by removing the front element. Give this old lens a new life. It's a macro shot of Samantha's left eye.

 

At first glance, the Canon EF35-80mm f/4-5.6 seems like a very average lens. However, if you can look past the plastic mount, slow aperture, and cheap build quality, this lens is by far the best macro lens out there for its price. A simple modification is needed to turns this otherwise ordinary lens into a super-macro lens that works in a similar fashion to the Canon MP-E 65mm. I removed the front sticker, unscrewed 3 retaining screws, and removed the front 3 elements (the AF elements). Please check youtu.be/5a6n_OAmjSg With these elements removed, the lens is focused by either zooming it in/out or by moving the camera back/forth, just like one would do with the MP-E 65mm 1-5x macro lens. The loss of autofocus is hardly a concern since the camera will still tell you when you hit the currently selected focal point, so I tend to use those and shoot as soon as you hear the beep of your camera. After the mods, I would say that this lens goes from around 1:1.5 to ~2:1 life size magnification. Truly amazing results for something I bought for less than 25 EUR in an Used Product store. Indeed, even dedicated macro lenses can't exceed 1:1 magnification without using extension tubes. And, to make the deal even sweeter, you still get full electronic metering and aperture controls just like you would with any other EF lens. The focussing distance is tiny, at 35mm you have maybe 5cm and more like 2cm at 80mm, it's not a very easy lens to use, but this is what makes getting the good shots so much more rewarding! More 35-80 macro's can be found: www.flickr.com/groups/3580macro/

 

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Taken on January 4, 2015