I would say landscape photography is the most underestimated genres of photography. Budding photographers often think there is nothing really to it and anyone with a decent enough camera can produce great landscape images. Well just as every cat has its day, a great camera will surely get it right some of the time. But for consistent results you cannot simply leave everything to the camera.To make great landscape imagery you will need meticulous preparations and a deep understanding of the basics of exposure.
To their advantage a landscape photographer has quite a bit of freedom to play around with. That means, he is at liberty as to how he chooses to expose for his compositions. E.g., a scene which has a lot of contrasts with tones transgressing into pure black and pure white, a photographer may be pardoned for showing a bit of prejudice towards highlights. It is entirely up to him. It is not bizarre to see high-key images of landscape scenes which have an almost washed out feel to them except for the one key element that dominates the composition. Most landscape photographers, though, look to maximize the dynamic range, or the range of tones between pure black and pure white.This is visually appealing and is something that has come to become synonymous with landscape photography.
The two factors which actually make a huge impact on your landscape compositions are – tonal range and depth of field. This discussion will revolve around these two aspects.
Depth of field
First up is depth of field. Depth of field, truly speaking, is one of the major if not the most important factor that determines the quality of your images. If you look at images right from the classical ages of film photography and those from the period even before that, shot on larger 4 x 5 or 8 x 10 formats, you will easily identify this to be a common theme. Everything from the foreground right up to the farthest object in a landscape image is usually sharp. This is achieved by using a small aperture.
So, theoretically, landscape photography is best done with the lens stopped down to its lowest aperture. However, there are some technicalities which makes this optically unsuitable. As you stop your lens down from one f-stop to the next (progressively smaller aperture), at some point lens diffraction comes into play. Lens diffraction is the loss of image sharpness as a result of the light waves hitting the aperture blades and dispersing. Evidently this means the advantage of using smaller aperture is mitigated.
Sometimes, photographers confuse between depth of field and image sharpness. They are not the same thing. Image sharpness depends on a lot of factors, one of them being lens diffraction. Another factor is the camera resolution. The same resolution factor however, can accentuate the effect caused by lens diffraction. Without going too much into the mumbo jumbo of it, higher the resolution your camera hasmore it is going to be affected by lens diffraction.
What it means is you need to negotiate a balance between the smallest aperture that you want to use and the resulting loss of sharpness. The biggest depth of field is achieved between f/8 and f/16. Cheaper lenses will be affected by lens diffraction at around that range. Plus, if you have a high resolution camera the effect of diffraction will be accentuated. When selecting the aperture for your landscape images keep this in mind.
The use of the right accessories
Speaking about landscape photography accessories one has to emphasize on the most important one – the circular polarizing filter. The C-PL is probably the most important of all the accessories and certainly the most important filter of all. If you can have only one, invest in a good quality C-PL. It is primarily used to remove reflections and glares. E.g., if you are shooting a brook and the shimmering water under direct sunlight is creating all sorts of issues for you, simply attach a C-PL to the front of your lens, rotate it gently and voila the reflections are all gone! C-PLs, as such, tend to saturate color, enhancing the natural hues of the sky, the vegetation and even rocks. It can also cut through haze which tend to make some compositions appear warmer.
There are some downsides to C-PL usage though. If you try to cut corners and buy a cheap piece of filter you are likely to see some drop in optical performance of your lens. Mind you, the C-PL sits in front of your lens. That means light has to pass through an extra layer of glass and air. If the quality isn’t as good as the lens behind it, your images are going to be below par.
Plus C-PL filters block away some light because they allow light waves vibrating in a particular orientation to pass through rejecting everything else. If you don’t counter for this when setting your exposure your images are going to be dark.
ND filters are the second important set of filters you need. I say set because unlike a C-PL where you can dial the filter to increase or decrease its effect, with NDs it is more like what-you-see-is-what-you-get. Thus, at the bare minimum you will need a three or four. A one-stop, two-stop and three-stop filter in both solid, graduated and reverse graduated versions plus a filter holder and a set of adapter rings. Adapter rings will allow you to use the same set of filters for all your lenses without having to buy separate filters for each one of them. These filters stop all wavelengths of light across the visible spectrum making it possible to use a wider aperture or a longer shutter speed when it is otherwise impossible.
Shooting in RAW
Shoot in RAW for all your landscape images. RAW is an uncompressed format that saves all of the image data without processing them. Once the optical information is transformed into a JPEG image it is basically flattened with little chance of further processing. Things like retrieving details from shadows, increasing contrast and using warming filters are no longer possible. Every change you attempt on a JPEG image is not without destroying some information in it.
Using the correct White Balance
Never use the auto white balance mode. At the bare minimum, if you are unsure of the right white balance settings, use the preset options in your camera. All cameras (even the ones on smartphones) come with a few basic white balance presets. Set it to cloudy if you are shooting under overcast conditions, set it to daylight if the sun is out. For indoor shooting use the right white balance preset depending on the dominant ambient light source such as tungsten or fluorescent or flash.
Using long exposure
Without an iota of doubt long exposures are what makes a majority of landscape images really pop. There is something about the hint motion in a still image that sweeps the viewer of his feet and draws him into the composition. Long exposures are certainly a lot more practical when you use them in combination with smaller f-stops. But for the right effect you will need to make sure that you have the right ND filter to stop some additional quantity of light and pull off such an exposure.