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A Reason to Combine Gradient Neutral Density Filters and Bracketing in Landscape Phot

When the dynamic range of a scenery is very large, it might be necessary to use some kind of trick in order to keep it inside the histogram. At least, if you want to prevent pure white or black in the picture. Some use filters, others use bracketing. But why not use both?

For the photographers who don’t know, the dynamic range of normal daylight scenery can reach up to 18 stops. That is the equivalent to approximately 100,000 luminosity levels between pure black and pure white. That is what I have learned and if I am mistaken in some way, please let me know.

Those 18 stops is more than normal camera sensors can record. The best on the market at this time will be able to go up to 14 stops, perhaps a bit more. But the majority of sensors can record up to a maximum of 12 or 13 stops, which is a lot also.

There are a few restrictions to it. You will need to shoot in raw file format, and your camera will need 14 bit depth in order to be able to record that many luminosity levels. You will need to push down the bright levels, and pull up the dark levels in post-processing a lot to make it visible. The possibilities and results can be truly amazing. But there are also downsides to this kind of image recovery.

When pulling up the darkest parts of an image, a lot of noise may occur. The more you recover the blacks, the more prominent noise will become. That is why it is best to expose to the right, in order to maximize the amount of detail in the darkest parts of the image. At the same time it is important to prevent the highlights from clipping. Because that is never recoverable.

High Dynamic Range in Landscape Photography

Yes, this is mainly about the dynamic range of landscapes. Depending on the moment of day, and the weather conditions, these scenarios can have the large dynamic range I mentioned previously. In the worst case scenario it can reach up to 18 stops. This basically means you will have 4 stops short when you use a camera with 14 stops of dynamic range. The resulting image will have pure white in it, or pure black, or both. Especially for landscape photographers this is often an unwanted situation.

Fortunately there are solutions available for these situations and I guess we all know about these workarounds. Let me mention every solution, together with its downsides.

Solution 1: Use Your Sensors’ Dynamic Range

This is something that is perhaps the most obvious one. By an exposure to the right, the maximum amount of dynamic range can be captured. It will need a significant recovery of the shadows, but if performed well, you can get up to 14 stops of dynamic range in one single shot.

The downside is the risk of increased noise in the recovered dark areas. Even with the very well performing Sony a7R III it will show a very noticeable amount of noise. Also the scenery can have more dynamic range than the camera is capable of, resulting in pure white, or pure black. So this solution has its limits, depending on how the camera is performing and what you are shooting.

Solution 2: Use a Bracketing Series

A bracketing series is a certain number of photos with different exposures. Most photographers are familiar with it. This solution makes it is possible to capture a limitless dynamic range. In theory that is. With a series of 5 images with one stop increments, together with the dynamic range of the camera, you should be able to capture the 18 stops dynamic range of a bright sunny day.

Even with bracketing, you have to rely on the dynamic range of the camera. It will explore the limits of the sensor, thus increasing the risk of noise in areas that were initially are very dark. But compared with the first solution, it will have a tremendous increase in image quality. Of course you can increase the amount of images in your bracketing series, but it has to be workable. It is no need to shoot more than necessary.

Solution 3: Use Gradient Neutral Density Filters

The use of gradient neutral density is not everyone’s cup of tea. But if you love using gradient neutral density filters, you are able to reduce the amount of light in a part of the scenery, thus decreasing the dynamic range. Filters can reduce up to 4 stops of light, and even more when filters are stacked. 

For this method you will need to make a relatively large investment. Filters are expensive, and it can be a hassle to bring those along. It also takes a lot of time to setup. At least, more time than a bracketing series, for instance. But the real downside of filters is the straight line of the gradient. Whenever mountains or trees break through the horizon, these will be darkened also. Even with rotating the filter, the gradient will almost never follow the lines of the landscape.

Solution 4: Why Not Combine Bracketing and Gradient Neutral Density Filters?

Every solution I mentioned so far, works in a lot of situations. It also has its downsides, as I described. Perhaps you can come up with a few others also. But why not use filters and bracketing at the same time? I started to combine both ways after I noticed how each of the solutions on its own did not have the results I wanted. Bracketing gave me to much risk in increased noise levels, while filters had the problem of a straight gradient. 

By using a gradient neutral density filter, it is possible to reduce the amount of dynamic range in a scenery up to three or four stops. But together with bracketing, you don’t have to use the darkest gradient filter anymore. Just by reducing the amount of light by one or two stops it is no longer necessary to go into extremes with bracketing. Just use a gradient filter to reduce the brightest part of the image, and shoot a bracketing series to capture the remaining dynamic range.

This way you prevent too much darkening in objects that break through the gradient of the filter. At the same time you prevent the necessity to go into extremes with bracketing. It will reduce the risk of too much noise.

Use the Strengths of Each Method and Avoid Its Weaknesses

Perhaps you prefer dealing with with large dynamic ranges by bracketing. Or perhaps you really hate bracketing and prefer the use of filters. You may have your own personal reason to use one way instead of the other. But I believe there is no need to stick with one and ignore the other. Why not use the strengths of both ways? It is the final result that matters, and you can use whatever solutions you like. In the end I think combining gradient neutral density filters and bracketing makes it more easy to shoot the picture you want.

What do you think about capturing a scenery with the complete dynamic range intact? What solution do you have for getting the result you like? Do you use filters, or bracketing? Or both? Or perhaps a method I did not mention? Please share your thoughts in the comments below. I am looking forward to your reply.

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