Trying to learn about bohek

gmomto5 · Feb 22, 2012

Hi all, I'm hear to learn from you guys, I have absolutely nothing to add to this forum now, maybe one day. I'm trying to learn about blurring the background on my Nikon D90. This morning I have learned that I have to stop the camera down to do this. I've tried it a couple of times, but don't seem to be getting the blurred background results I'd like to get. Does anyone have any suggestions to offer me? I'm shooting Nikkor 70-300, 18-105, and a wide angle that I've never tried shooting. Any tips appreciated.

blackrose89 · Feb 22, 2012

Well first things first, it's spelled "bokeh" :lol:

.

480sparky · Feb 22, 2012

"Stopping down" increases DOF, and decreases bokeh. You need to 'open' the aperture up (smaller f/stop number).

o hey tyler · Feb 22, 2012

Do you know what "stopping the camera down" consists of? Because that sounds counter intuitive.

Also, it's 'bokeh", however 'bohek' sounds pretty funny, I will admit!

Bokeh is not anything adjustable, it's a characteristic of your lens(es). DoF is controlled by

Aperture
Distance from Camera to subject
Focal length

I suggest you read up on those, and play around with your camera to find out how to get circular OOF highlights. It's the best way to learn about DoF.

Big Mike · Feb 22, 2012

To have part of your image, intentionally blurry, you will want to create a shallow Depth of Field. There are a few factors that contribute to the DOF, the most important of which, is the lens aperture. To get a shallower DOF, you will want to use a larger aperture (lower F number).
(by the way, "stopping down" refers to making the aperture smaller (higher number), so that's not what you want to do).

MReid · Feb 22, 2012

70-300 wide open, set it to 300mm & focus on an object 10 feet away with a background that is not to close.
What you see in that unfocussed background is the bokeh of your lens....or look of the defocused areas.

cgipson1 · Feb 22, 2012

Bokeh is the result of several things... Aperture (and how that is affecting the DOF), your distance to your subject.. and the subjects distance to the background.

Typically if you use a large aperture... with the resultant decrease in DOF... it makes it easier to get the type of OOF background you are referring to. The DOF has to encompass the subject.. but not the background...

try looking at this... set it up for your lenses.. and see if it makes sense. Online Depth of Field Calculator

Derrel · Feb 22, 2012

The most important factor in DOF is not the lens aperture; it is camera-to-subject DISTANCE....that is a much more fundamental factor in depth of field. For example, at f/2.8 at one foot, the DOF is quite shallow. At f/16 at one foot, DOF is also fairly shallow. At 200 feet, depth of field at f/2.8 is quite expansive, as it is at f/16. If aperture were the "most important factor" in DOF control, then the 200 foot performance of a lens at both f/2.8 and at f/16 would not be similar.

The physical size of the capture medium (sensor or film) is also a hugely important factor in depth of field. For every given angle of view, the smaller the format, the deeper the DOF is.

Mot · Feb 22, 2012

BOKEH!!!

Yeah, open the aperture up. Not stop it down. Use the smallest number your lens offers; that's the biggest opening. This one was shot at f/1.4, that's relatively wide for DSLRs. Rangefinders are famed for having super fast lenses; some open to f/0.95 such as those by Canon and Leica.

Play around with the camera to subject distance, too. That also plays a major role.

Dao · Feb 22, 2012

- Aperture, wider the better (lower f number)
- Focal length, longer the better.
- Distance between subject and camera, shorter the better.
- Distance between subject and background, longer the better.

gmomto5 · Feb 22, 2012

blackrose89 said:
Well first things first, it's spelled "bokeh" .

Well I guess I wasn't paying attention to my spelling! Thanks

Redeyejedi · Feb 22, 2012

Derrel said:
The most important factor in DOF is not the lens aperture; it is camera-to-subject DISTANCE....that is a much more fundamental factor in depth of field. For example, at f/2.8 at one foot, the DOF is quite shallow. At f/16 at one foot, DOF is also fairly shallow. At 200 feet, depth of field at f/2.8 is quite expansive, as it is at f/16. If aperture were the "most important factor" in DOF control, then the 200 foot performance of a lens at both f/2.8 and at f/16 would not be similar.

The physical size of the capture medium (sensor or film) is also a hugely important factor in depth of field. For every given angle of view, the smaller the format, the deeper the DOF is.

excellent point!
sensor plane to subject: subject to background distance, aperture and type of lens affect DoF, however it's the lens' construction that dictates quality and shape of the bohek, or bokeh as it is more commonly referred to.

thanks for that big mike, good reference.

gmomto5 · Feb 22, 2012

You guys are awesome. Thanks a bunch. When I get home I'm going to play around with my 70-300 and backgrounds. I'll move my subject away from the background and try several different aperture settings, starting with the lowest that my lens will go and see what I get. CAMERA TO SUBJECT DISTANCE, gotta remember that. Maybe with all this help I can get a decent photo out of this expensive camera equipment I have invested in. Thanks,

Derrel · Feb 22, 2012

The term bokeh was introduced to the English-speaking world in the 1990's in a series of articles written by Mike Johnston. Bokeh refers to the CHARACTER of the out-of-focus areas in a photograph. It is not just about how a lens renders out of focus point sources of light, as shown in the photo above in post #9. In common parlance, bokeh is often used as a description specifically of photos made in situations where there are point light sources in the background, but that is NOT the entirety of what the term means. Some people, like KmH, refer to the point light source rendered type of backgrounds as "Hollywood Bokeh". How a specific lens creates its out of focus point light source highlights is seen in many,many Hollywood movies; the opening sequence of the Scarlett Johannsson (sp?) and Bill Murray film "Lost In Translation" is like a huge, multi-minute homage to Hollywood bokeh.

The way a lens renders out of focus areas varies a lot from lens design to lens design. Many people are unable to "see" or to appreciate, or to even accept, the concept of bokeh. Just as many people claim they cannot tell good wine from bad wine, and that "all wine is the same--yucky". Look for the Mike Johnston articles and blog entries on bokeh,and go back to the ACTUAL SOURCE OF THE TERM in ENGLISH if you'd like to understand it; don't listen to the masses on Flickr...