Want to know about F/8-F/11 in-spite of aperture?

Question

I just grab some information about the best fit of aperture, can we make something different between F/8 & F/11.According to my best knowledge and past photography experience that when we make our aperture at its minimal position to get object in focus i.e F/22 – F-32, in this position we are at position to make blur with some software. In this case we were unable to create such sharpness effect.

My question is that how we can achieve this aperture’s accomplishment. Is it a perfect compromise or a best optical ratio?

I fail to understand your question. Are you asking why aperture range f/8-11 is said to be better than f/22-32? Take a look at answers given to this question about aperture. — Esa Paulasto, Aug 28 '13 at 04:43
possible duplicate of How can I take photographs with a large depth of field? — mattdm, Aug 28 '13 at 11:41

score 0 · Answer 1 · answered Aug 28 '13 at 10:06

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The best aperture is the one that suits your picture.

Lenses are usually sharpest 2 stops below the widest aperture.

In an APSC sensor, F8 and narrower starts to have detrimental effects in image quality due the diffraction of light.

answered Aug 28 '13 at 10:06

fortran

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Diffraction is not related to sensor size, it's only related to pixel size. And I'm not sure that all lenses is at it sharpest 2 stops down. – Håkon K. Olafsen Aug 28 '13 at 13:16
I don't say that all lenses are sharpest 2 stops down; I said 'usually' because it's a rule of thumb. About diffraction and the sensor size, it depends in the magnification, of course if you are going to look to a 1:1 crop then it depends on the pixel size, but for equally sized prints, then the pixel size is largely irrelevant and only the sensor size matters. – fortran Aug 28 '13 at 13:28

score 0 · Accepted Answer · answered Aug 28 '13 at 13:41

I agree with Hakon. There are several factors relevant here. First, no lens is perfect. The tricky bit is the edges of the lens, which are less perfect optically than the middle part of the lens. When the lens is "wide open" (i.e. the aperture hole is at its largest size), then there is a bit of distortion caused by the edges of the lens. Pro photographers generally consider f/8 to the the "sweet spot". Closing the aperture down to f/8 eliminates light rays from the edges of the lens elements.

Second, above approximately f/8, the smaller you make the aperture (i.e. the larger the f/number) the more distortion you get from an optical phenomenon called "diffraction".

Third, the smaller you make the aperture, the greater is your depth-of-field. DOF is the range between the nearest object in focus and the furthest object in focus.

Fourth, if you have a zoom lens and use a wide angle setting while getting closer to the subject, you will get MUCH better DOF. Most photos that appear to be sharp for both very close any very far objects are shot with the lens set at a somewhat wide angle setting.

There are a lot of fancy tricks you can use to increase your DOF, such as focus stacking, but these are pretty advanced techniques.

Hope this helps, Dave

Want to know about F/8-F/11 in-spite of aperture?

2 Answers2