Aperture size for landscapes.

I've been looking at a lot of landscape photos on this forum and the net lately and noticed that many seem to use apertures around f8-f16. I almost always use the smallest aperture possible (f22 for my lens) and adjust the shutter speed to get the right exposure. The only time time I use a smaller aperture is if there is moving water or clouds are moving fast or it's windy, and would like faster shutter speeds.

If you want as much of the picture in focus as possible, what is the advantage of using larger apertures (i.e. f11 vs. f22) in landscape photos if you have have a good tripod.

Less diffraction.

At f11-16 you can usually get everything in the frame in acceptable focus anyway.

Well if you calculate the DOF for most landscape photos where the subject is far away, youre not getting much more than in focus by going from 11 to 22. For example if youre getting a vast landscape, at 28mm on a 7D with the subject 700ft away. the difference in DOF between f11 and f22 is 6feet.

While going from 11 to 22, you to gain the 6 feet, what you do get is diffraction. Diffraction happens at smaller apertures. Diffraction makes the image soft. So you will get "more" in focus but a softer image. For some people, they use the largest aperture that allows sufficient DOF, so they could retain sharpness.

imjason wrote in post #14997382
While going from 11 to 22, you to gain the 6 feet, what you do get is diffraction. Diffraction happens at smaller apertures. Diffraction makes the image soft. So you will get "more" in focus but a softer image. For some people, they use the largest aperture that allows sufficient DOF, so they could retain sharpness.

But if the foreground is important, having it be slightly less sharp is far better than having it be out of focus. Hyperfocal at like f11 is the way to go if you can estimate well enough.

An option is to do multiple shots with different apertures and focus points and use a focus stacking tool to compile the shoots. You have to work quickly to minimize ghosts from any anything moving between the shoots.

http://www.heliconsoft​.com/heliconfocus.html
http://zerenesystems.c​om/cms/stacker

Isn't focus breathing an issue with focus stacking, especially with ultra-wide angle lenses?

I read an article about this method in Outdoor Photographer, and the consensus was (AFAIR) that whenever you try focus stacking there is going to be a lot of post processing involved to fix that.

Thanks for the info guys. My photos looked a little soft at 100%, but I always thought it was because of my camera (40D 10mp). Will try out a larger aperture next time I go out.

Is "softness" from diffraction lens dependent? i.e. does the amount of diffraction at f22 similar from one lens to another, or do higher quality lenses have significantly less diffraction.

Diffraction is caused by the size of pixels on the sensor relative to the aperture size. So it is a sensor property, not a lens property.

Read up on hyperfocal distance if you are worried about foreground focus. Often infinity focus is not your best choice for landscape.

tkbslc wrote in post #15000520
Diffraction is caused by the size of pixels on the sensor relative to the aperture size. So it is a sensor property, not a lens property.

Read up on hyperfocal distance if you are worried about foreground focus. Often infinity focus is not your best choice for landscape.

I'm afraid I've got to disagree on this one as written. Diffraction is an optical phenomenon relating to the size of the aperture, and in itself is purely a lens property. The sensor (pixel size/density) relates only to the final "systemic" effect of the diffraction, which is perhaps what you meant. Here's an excellent discussion:
http://www.cambridgein​colour.com …ffraction-photography.htm

mhrok wrote in post #14999861
Isn't focus breathing an issue with focus stacking, especially with ultra-wide angle lenses?

I read an article about this method in Outdoor Photographer, and the consensus was (AFAIR) that whenever you try focus stacking there is going to be a lot of post processing involved to fix that.

Nope. Well, it is an issue, but you get/buy software to deal with it and it works very well with little or no user-processing in a lot of situations. Sometimes some touch-up is needed in the form of selecting which image to use in various areas, but I've never had a problem with image alignment and re-sizing.

Focus stacking has 2 issues:

1. if stuff moves, you have to decide which fame to use for both where the subject was and where it moved to (well I think you get the idea). For moving clouds this is not a problem, because you will use the shot focused at infinity. For anything else it might be an issue, but might not, especially if you have enough DOF to get the moving subject and whatever is behind it in focus at the same time (e.g. moving tress or grass).

2. if you have a foreground object that is very OOF when the background behind it is in focus then it will mask part of the in focus area and you will get a halo. There is no way around this except increase DOF. basically there is an area of the scene for which you never get a sharp image.


To counteract both these issues I often focus stack at f11-f16 (on FF - f8 - f11 on new/15-18MP crop sensors). Even if everything is theoretically in hyperfocal distance, you can get a much, much sharper overall image. Being on the edge of the hyperfocal DOF is much worse than the diffraction at f16.

For the 40D, it looks like you should be relatively safe up to f16, but if in doubt maybe take some shots at different apertures. Another method would be to 'aperture stack' - take various shots at different apertures and select the sharpest parts of each. This only requires the use of layers and masks, no special software.

Oeijur wrote in post #15000148
Is "softness" from diffraction lens dependent? i.e. does the amount of diffraction at f22 similar from one lens to another, or do higher quality lenses have significantly less diffraction.

So as stated, no, the diffraction is the same. However, what is often not mentioned is that the diffraction is simply another part of the sharpness equation. I was thinking about this when I was considering that 'shooting at f22 turns your $2000 lens into a $200 lens', but reality is it doesn't. A sharper lens with diffraction may well still be sharper than a softer lens opened up. This is especially true around f11-f16 where the diffraction calculators say you are diffraction limited. Contrary to seemingly popular belief this does not mean that every lens will now be just as soft/sharp as any other.

I've found that f/8 and f/11 are what I use the most, sometimes going up to f/16 if things are just too bright and I want a longer shutter speed. If I need it darker than that, I use my ND filters to knock the light down a couple of stops.

Take a look at DoFMaster (especially if you have an Android or iOS smartphone); you can get their app and plug in your current conditions to get a pretty reasonable hyperfocal estimation. Then just get good at "eyeballing" your distances This will help you keep a good sharpness from front to back, even when your foreground subject is relatively close in the frame. As Taylor says, simply focusing out at infinity is, frequently, not what you really want to do.

It depends on the lens i use. My 15-85 is my sharpest lens at f/22, so that's my preferred aperture with this lens( it's more than sharp enough at f/22, but falls apart at f/25). With my 10-22, i tend to stay under f/16.. and preferably f/11.

On 60D/T2i.

ejenner wrote in post #15011087
So as stated, no, the diffraction is the same. However, what is often not mentioned is that the diffraction is simply another part of the sharpness equation. I was thinking about this when I was considering that 'shooting at f22 turns your $2000 lens into a $200 lens', but reality is it doesn't. A sharper lens with diffraction may well still be sharper than a softer lens opened up. This is especially true around f11-f16 where the diffraction calculators say you are diffraction limited. Contrary to seemingly popular belief this does not mean that every lens will now be just as soft/sharp as any other.

Good point, but no matter the cost and quality of the lens, isn't it always best to know your lenses sweet spot and shoot in that range when shooting landscapes at a distance and only using higher apertures when focusing closer to the camera?

-1.4-