Which aperture setting takes sharper images. f/8 or f/11?

[raaskohx10]

Any idea which aperture setting is better for taking sharper images of landscapes? I read on another forum that f/8 or f/11 take sharper images (why not f/9 or f/10 then?). Your views/comments will be highly appreciated.

 

[thetrue]

Different lenses have different " sweet spots".

 

[Overread17 5]

Assuming that you are using the base ISO value for your camera (this is the base ISO value, it might not be the same as the lowest ISO value - eg many Canon cameras use ISO 100 as their base whilst many Nikon use a base of ISO 200) - and assuming that the shutter speed is fast enough to ensure that there is no motion blur - and that the camera is tripod mounted (or that the shutter speed is also fast enough to overcome handholding shake) then the sharpest aperture will - vary.

It will vary because of the difference in the nature of the optics of different lenses and sensor/film format sizes. In a very general term f8 is where the majority of lenses on the majority of cameras produces a "sharp" photo. Specifically where the sharpest point lands will, however, vary from lens to lens and is something you'll have to do some boring test shots to see. It will also vary because of the sensor/film size as well - since this affects the circle of confusion and the circle of confusion affects how soon diffraction starts to take effect.

Diffraction is a process which introduces softness into your photos as you use smaller and smaller apertures, however just where it appears will vary lens to lens. On some it might appear right after f8 - on others maybe after around f10.

So "it varies" is likely the best answer you will get. You'll have to research and test to see how your setup responds and where the sweet spot for that lens exactly lies.

 

[Tuffythepug]

I think the idea is that most lenses tend to be the sharpest at their center. An aperture of F8 or F11 generally assures that you will be taking advantage of that fact. F9 or f10 is fine as well; keep in mind that cameras used to have only specific apertures available: f2, f4, f5.6, f8, f11, f16, f22 etc were all you had available; there were no in-betweens. (well I guess some had half-stops) but you get the idea.

 

[raaskohx10]

Thanks guys for your valuable comments.

 

[Buckster]

I find it worthwhile to run a series of tests when i get a new lens to determine where my sweet spots are with that particular lens. I use what I need to for the shot, but it's good to know for when clarity to DOF really is an issue I want to address.

I use a standard color chart and a Amazon.com: LensAlign MkII Focus Calibration System: Electronics these days, but I used to use a simple ruler to work it out.

It also gives me the opportunity to make sure the lens is performing well straight from the manufacturer, and whether I need to dial in any focus calibration on the camera for that lens.

 

[raaskohx10]

Thanks.

 

[amolitor]

It's possible the OP really wants to know about depth of field here.

f/11 will give you a photograph where more of the subject matter (front to back) is "in focus" more or less, than f/8. This is what "greater depth of field" means.

Depending on the lens, the stuff that is most in focus may be sharper or less sharp, at f/8 or at f/11. That is, the thing the lens is actually focused ON will be sharper at one, and less sharp at the other, and which it is depends on the lens.

 

[thetrue]

It's possible the OP really wants to know about depth of field here.

f/11 will give you a photograph where more of the subject matter (front to back) is "in focus" more or less, than f/8. This is what "greater depth of field" means.

Depending on the lens, the stuff that is most in focus may be sharper or less sharp, at f/8 or at f/11. That is, the thing the lens is actually focused ON will be sharper at one, and less sharp at the other, and which it is depends on the lens.

Oh shiznit, that never even crossed my mind!

 

[Solarflare]

My own 35mm f1.8 has its sweet spot at f/4; f/5.6 is already worse than f/1.8. At least thats what the lab reports; I cannot distinguish between f/1.8, f/2.8, f/4, f/5.6, f/8 or f/11 by looking at pictures, even with 100%. The shallow depth of field from f/1.8 or the low amount of light at f/11 is much more of an issue really(*), so I basically just use my lens at whatever aperture that yields good results..

The D800(E) is already limited by diffraction above f/5.6. The old D700 reportedly doesnt start to get problems with diffraction before f/11.

(*) I never use tripods and in fact I dont even have one, so low light is a big problem for me.

 

[fjrabon]

My own 35mm f1.8 has its sweet spot at f/4; f/5.6 is already worse than f/1.8. At least thats what the lab reports; I cannot distinguish between f/1.8, f/2.8, f/4, f/5.6, f/8 or f/11 by looking at pictures, even with 100%. The shallow depth of field from f/1.8 or the low amount of light at f/11 is much more of an issue really(*), so I basically just use my lens at whatever aperture that yields good results..

The D800(E) is already limited by diffraction above f/5.6. The old D700 reportedly doesnt start to get problems with diffraction before f/11.

(*) I never use tripods and in fact I dont even have one, so low light is a big problem for me.

You know the term 'limited by diffraction' or 'diffraction limited' actually has a very specific meaning, and it's actually a good thing. Diffraction limited means that chromatic aberration distortion is almost entirely gone, and sharpness is almost entirely harmed by diffraction, which can never be fully eliminated, even in a theoretically perfect lens.

Further, where are you getting these f/5.6 claims? Sure, the D800 is a little bit worse for diffraction than some cameras, because of it's absurd pixel density. However, even the harshest critics tend to say it suffers around f/8 (and even then, only in the green color wavelength, since different colors can have different issues with diffraction), and in reality, I've never seen anybody that notices it until f/13 or so. Additionally, a lot of this softness from diffraction is mitigated by exactly what is causing it, the pixel density, and thus resolution. Essentially diffraction that is exacerbated by pixel density doesn't mean that a camera is less sharp than a more pixel dense camera, it just plays a role in causing the diminishing marginal returns of increased pixel density. I could perhaps understand if you had made these claims on the D3200, which crams 24.2 MP onto an APS-C sensor. But as best as I can tell you pulled the f/5.6 number out of your behind. Since this isnt a camera you own, and these claims seem to contravene most everything I've seen or read or experienced when using a D800, what is your source?

Further, since your D5100 is roughly just as pixel dense as the D800, you'd be claiming that your camera also is 'limited by diffraction' at f/5.6

 

[ph0enix]

F-number - Wikipedia, the free encyclopedia

 

[enzodm]

Any idea which aperture setting is better for taking sharper images of landscapes? I read on another forum that f/8 or f/11 take sharper images (why not f/9 or f/10 then?). Your views/comments will be highly appreciated.

it you are speaking of your kit lens, from Photozone tests, f/8 would be better (sweet spot for resolution is at f/5.6, but read also amolitor post).
About why not in the middle, consider that 1.4, 2, 2.8, 4, 5.6, 8, 11, 16, 22, ... are the equivalent of integer numbers in aperture (full stops), so anything in the middle is fractionary. While in digital photography we are used to split hairs in 4000 (pairs ), the marginal change you could have considering also those middle f/numbers can be gained or lost with a small gust of wind, so it's not worth to optimize at that point. Even the difference between f/8 and f/11 could be nonessential if you shoot in a non ideal way from other points of view, e.g. no tripod, no mirror lock, high ISO, etc.

 

[raaskohx10]

In order to make the point more clear I have taken few shots with Kit lens Canon 18-55 mm IS-II. The subject ( a match box) is placed at a distance of about 7 feet on a cement block and there is a wall in the background at a distance of about 6 feet from the subject. Shots have been taken at various aperture settings with fixed ISO of 100 and focal length of 55 mm. I have noticed that sweet spot of lens is at following apertures f/8 to f/13. (all pics have been cropped).

 

[enzodm]

The basic idea is correct (for 55mm only), however I hope also you manually focused every image. If not, a slight front or backfocus will have effect (blur) only on larger apertures, giving the false impression of better sharpness for smaller apertures (greater DoF).