Question by stacey: A question about aperture and bokeh?
I have recently received a Pentax SF10 SLR (35mm). It has an adjustable aperture piece. If I were to take a bokeh shot, what should I set the aperture to?
The numbers go as follows:
22, 16, 11, 8, 5.6, 4
Also, how would I go about creating the best bokeh shot?
Best answer:
Answer by brokendown321
you would want to use f4. the lower number is a wider aperture, which has a shallower depth of field. because it is a large aperture it requires less light and therefore slightly lower light settings lend themselves to bokeh shots. you can always shoot at a high shutter speed if you want to shoot with bokeh in a bright environment.
you may want to play with the perspective to maximize the bokeh. when photographing people or objects put a good amount of space between them/it and the background to ensure that you get the maximum bokeh.
Know better? Leave your own answer in the comments!
you need the widest aperture (4), you need to get as close as possible to the subject, and then move the camera around until you see pleasing bokeh in the background.
good luck! p.s. the best bokeh shots are with lenses that go past 4 to 2.8 or 1.4, but you should be able to do it if you have the right backdrop.
Bokeh just refers to how the lens handles out of focus images, if you mean the pictures where the background is blurred, but the subject is sharp then its called selective focus.
This uses a shallow depth of field to throw the background out of focus, only two things affect depth of field, one is magnification and the other is aperture.
The more you magnify whether by using a telephoto or simply by moving closer the less the depth of field gets.
The wider the aperture also makes for less depth of field.
Your lens can only go to f4 so the effect will not be dramatic (unless it was a telephoto lens), a wider aperture lens would offer you more scope.
You can compensate for this to some extent by having the background a long way behind your subject.
The best combination is a telephoto lens (70mm +) the longer the telephoto the more the effect (they magnify more), together with a wide aperture. Unfortunately these are expensive lenses.
Chris
The short answer is f/4
BUT…..
You need more information than that to get what you are looking for. What you are after is what we call a very narrow Depth Of Field. And there are THREE contributing factors to depth of field. Not just aperture value alone.
There are three factors to consider.
1) Aperture Value
2) Distance to subject
3) Focal length
For a detailed tutorial on how that works, so you can get the shot you want EVERY time, go here and look for the DOF tutorial.
http://freephotographytutorials.blogspot.com/
Please listen to Screwdriver and you will be smarter than 99% of photography students. Bokeh is an element of some (not all) soft focus areas in a photograph. It relates to and used to describe the specular highlights of the out of focus areas.
And, depth of field is controlled by two factors image size in the viewfinder and aperture. Lens focal length is a bogus factor. People perceive a longer lens has a shallower depth of field, but that is due to magnification. There are minor variations due to lens design and focal length, but hardly perceptible and not a relevant factor.
If you look at tutorial example photos with the same f-stop and enlarge the wide-angle shots so that the main subject is as large as the telephoto shots you will see the same depth of field.