What is the preferred aperture of a lens for landscape photography?

Question

I've noticed that the wider aperture is more expensive on lenses. Two of Canon's lenses that they categorize as Landscape can be seen here. The EF 16-35mm f/2.8L III is twice the price of the EF 16-35mm f/4L IS. I can imagine that the price is either driven up by construction complexity or demand for a wider aperture.

When it comes to landscape photography, I'm under the impression a narrower aperture is desired for crisp clear images, f11-f22. Am I correct in thinking the f4 would be the better lens to buy, strictly for landscape photography, or am I missing something about using a wider aperture for landscapes? I understand that the wider aperture allows more light, but set up on a tripod, I don't think I'm concerned too much about speed.

I'm looking to understand more about apertures in landscape photography, and when a wider or narrower aperture is preferred.

Answer 1

"Landscape Photography" is a somewhat nebulous term. It doesn't, in and of itself, convey any meaning about the depth of field for the shot. One could go for everything sharp, and indeed, this is what most people assume landscape means. But it's equally possible that you'd want to isolate a subject by using limited DoF.

So, if it's a choice between f/2.8 and f/4 - you'd have to ask yourself how often you may want to throw the background. There is a noticeable difference between f/2.8 and f/4 when shooting wide open and creating bokeh - but the differences go away as you stop down. The two are both excellent lenses and I own the f/4 variant because, well, money is an issue.

When it comes to landscape photography, I'm under the impression a narrower aperture is desired for crisp clear images, f11-f22.

This is a bad impression to be under. Diffraction will start to rob you of image quality at those f/stops. Don't get me wrong, you may need to go there for other reasons - say you're trying to get some water motion and forgot to bring an ND filter...but if your goal is sharp photos, simply stopping down to f/22 is not the way.

If you're wondering the technique that many landscape photographers use in attempting to get everything in the frame sharp (including those flowers just yards away), you need to look into hyperfocal distance.

Online Depth of Field calculators make running various scenarios a bit easier if you don't want to learn the actual formulas involved. For example, using a 5DmkII and 28mm lens set to f/8 - the hyperfocal distance is 10.8ft - which will put everything from 5.4ft -> Infinity into focus.¹

If you were to instead set your focus on the object sitting at 5.4ft, you would have a depth of field from 3.6ft -> 10.7ft (thus, those mountains a mile away won't look too good).

I'm looking to understand more about apertures in landscape photography, and when a wider or narrower aperture is preferred.

Aperture is about controlling DoF and balancing this with ISO and shutter speed trade-offs. With most landscape, one has the benefit of using a tripod and being able to extend shutter speeds into longer ranges - in other words, the trade off feels less important. This frees you up to use aperture to control DoF - period. There is no "preferred" aperture - simply the one that gets you the DoF you want for the shot.

_{¹ Note that hyperfocal distance is a property of depth of field, and thus changes for the same image with different display sizes and viewing distances. If a DoF calculator does not indicate display size and viewing distance, it is probably safe to assume it is based on standard viewing conditions: an 8x10 inch size viewed from about 10-12 inches. If an image shot at "the" hyperfocal distance calculated for 8x10" is displayed at 16x20", the DoF will not reach all the way to infinity. There are DoF calculators that do allow designating intended display size and viewing distance. This one from Cambridge In Color has a 'show advanced' button to access the feature.}

Answer 2

Let's look at it in terms of depth of field.

DOF Master gives for Canon 5D (a full frame camera), 16mm focal length and f/2.8 a hyperfocal distance of 3.03 m. If you focus at 3.03 m, everything from half the hyperfocal distance (1.52 m) to infinity is in focus.¹ Do you have elements in landscape pictures that are closer than 1.52 m away? Probably not.

The f/2.8 is more expensive simply because it has more glass. It is heavier too. What you gain in speed is lost in lack of image stabilization. Although depth of field at f/4 is better, it is good enough anyway.

So, do you find handheld shooting important? If you don't wish to carry a tripod, choose the cheaper f/4 with image stabilization. Do you take landscape pictures in limited sunlight with a tripod? You may find the f/2.8 beneficial.

I would say where the f/2.8 excels is astrophotography, where you may have a combination of landscape and stars, or only stars. You cannot use long enough exposures when taking pictures containing stars because the earth is continuously rotating, and therefore, stars would become short star trails.

I would pick the f/2.8 if I had about $2000 to invest in a lens, because I want the possibility to take pictures containing stars not becoming short star trails. Or actually no, I wouldn't pick Canon, I would pick a third party manual focus lens that is even faster! Something like f/1.4 would be ideal for astrophotography.

So, as summary, speed may be important (e.g. astrophotography), but the f/2.8 is not THAT fast, so it sits between fast and slow lenses. Not being fast enough for astrophotography, it won't be chosen by many, and not having image stabilization and being too heavy and expensive, it won't be chosen by many others.

_{¹ Note that hyperfocal distance is a property of depth of field, and thus changes for the same image with different display sizes and viewing distances. If a DoF calculator does not indicate display size and viewing distance, it is probably safe to assume it is based on standard viewing conditions: an 8x10 inch size viewed from about 10-12 inches. If an image shot at "the" hyperfocal distance calculated for 8x10" is displayed at 16x20", the DoF will not reach all the way to infinity. There are DoF calculators that do allow designating intended display size and viewing distance. This one from Cambridge In Color has a 'show advanced' button to access the feature.}