Wednesday, 11 January 2017

how did you get that bokeh?

What is bokeh? In wikipedia, we can read the following definition:

“In photography, bokeh is the blur, or the aesthetic quality of the blur, in out-of-focus areas of an image, or “the way the lens renders out-of-focus points of light.” 

Differences in lens aberrations and aperture shape cause some lens designs to blur the image in a way that is pleasing to the eye, while others produce blurring that is unpleasant or distracting— “good” or “bad” bokeh, respectively. Bokeh occurs for parts of the scene that lie outside the depth of field. Photographers sometimes deliberately use a shallow focus technique to create images with prominent out-of-focus regions. 

Bokeh is often most visible around small background highlights, such as specular reflections and light sources, which is why it often associated with such areas. However, bokeh is not limited to highlights, as blur occurs in all out-of-focus regions of the image. Bokeh can also be viewed by forcefully blurring one’s vision whilst looking at a small light, like an LED The term comes from the Japanese word boke, which means “blur” or “haze”, or boke-aji, the “blur quality”. The Japanese term boke is also used in the sense of a mental haze or senility.” 


I love bokeh, but then again, who doesn’t? Those perfect circles, or hexagons, usually in the background, that make every picture sparkle like Christmas, warm the heart and give feelings of joy. Bokeh is addictive and delicious. As the above definition points out, there is “good” and “bad” bokeh, depending on which lens you are using, and what exactly is out of focus. Technically, all out of focus areas are bokeh. But only illuminated out of focus areas show up as discrete lighter spots, circles or hexagons that people normally associate with “pretty” bokeh. Certain lenses are known for producing a lovely bokeh, and they are usually prime, not zoom lenses. The two that I work with to produce awesome bokeh are Nikkor 50mm 1.8 and Tamron 90mm 2.8

HOW TO SHOOT BOKEH?

My favourite is illuminating the droplets in the distance. At it’s simplest, go to the park after the rain, when the sun starts shining again. Orient yourself towards the sun, but make sure you are not actually photographing the sun. Manual focus, make sure nothing is in focus, open the aperture as far as you can and take a picture of the grass. You will get most perfect bokeh circles all over the picture. Now, because you have lots of light, play with aperture setting, increase it to say f 8 and see what that looks like. Then, choose a strand of grass and focus on it, with enough sparkling droplets out of focus in the background and snap a picture. You get the idea how bokeh is captured.

Bokeh can be easily set up indoors. Some people use fairy lights behind the subject they are photographing, I like using a sheet of glass with waterdrops on it, behind or in front of the subject, make sure the droplets are out of focus, and shoot with a flash, to illuminate that water.

If you shoot high-speed droplets in a glass container, the splash on the walls will often show up as bokeh as well. Glitter in the background will achieve the same effect, as will simply raindrops on the window, as long as the sun is shining on them. In fact, if you are shooting bokeh textures, raindrops on the window are perfect for this.



SINGLE VS MULTIPLE EXPOSURE 

Single exposures will limit the appearance of bokeh to the aperture you are using for your main subject. So if you need f 22 to capture that droplet refraction, you will not be able to get circular bokeh with it. Traditionally, in film cameras, we used to do “double exposure” pictures, when we didn’t advance the film but we took the second picture “over” the first one and they would show up combined in a negative. Naturally, the two pictures can have completely different apertures, ISO and shutter speed in order to achieve really creative effects. These days only Nikon dslr has Multiple Exposure feature (Nikon d80, d200, d300 and above) and it really is awesome for when you want to shoot your background bokeh on f 1.8 and your main subject on f 16 or higher.


But even if you don’t have this feature, you can layer a bokeh texture over your picture in photoshop and achieve similar results.


A PERFECT CIRCLE 

Perfect circle bokeh can only be obtained with wide open aperture, such as 1.8 or 2.8. You may want to push it all the way up to 5.6., but beyond that, your aperture, and hence your bokeh, will start to look more hexagonal.


HEXAGONS

My favourite hexagon aperture is f 8, but you will continue to get these all the way up to f 22. But the higher the aperture, the more “grainy” the surface of bokeh will be, and you will have a more prominent “border” on it. 


HEARTS, STARS, SNOWFLAKES

You saw all those pictures with heart-shaped bokeh and wondered how the hell is this done. This is not a photoshop trick, but a very simple home-made filter you can make yourself and have lots of fun.

You'll need your classic 50mm 1.8 lens, which is essential for shooting “good bokeh” anyway. Following simple instructions in this tutorial make a cap filter for your 50mm lens, with any kind of shape cut out in the middle. Open the aperture fully to 1.8, make sure you have enough light and something sparkly out of focus and shoot that heart or butterfly-shaped bokeh, it’s that easy!



No comments:

Post a Comment