Filters help your film or digital camera capture what your naked eye sees in the scene in front of you. Now to an uneducated person you may think that the camera will capture the same thing that your eye sees but that is not the case. It will show you an approximation but there are times when you need to trick the film or the sensor into getting all of the information and not washing the scene out on the bright spots. That is where the graduated neutral density filter comes in to play. It helps you capture what you are seeing.
In short it helps you tame some unruly light and make it usable. It will help you add detail in the highlight and the shadow areas. A great example of this is shooting sunsets. Sometimes there are overly bright areas that look phenomenal in person. Vibrant and colorful and yet when you snap the shutter the bright areas turn white and bland. This is a prime example of where a graduated neutral density filter can save the shot.
This is not for every day use and you might only use it sporadically at best but it is likely to be one of the most important additions to your camera bag that you ever purchase. In fact if you try and use it on a bright sunny day you are likely to end up with a very sinister looking scene.
This is because the human eyes and brain do a great job of looking at something and then making minute adjustments to make them look right to us. The camera, at least the current batch of cameras, does not have that ability and they need a little help from the man behind the shutter to capture the beauty.
When to Use a Graduated Neutral Filter
Himachal Pradesh, India
As a general rule you should only reach into the camera bag and grab your graduated neutral density filter when you are faced with an extreme situation that tricks you camera lens into capturing something other than what is really in front of your eyes.
That is, if there is an extreme contrasting lighting situation in your frame.
Generally, the contrasting lighting occurs in the following situations:
- Sunsets / Sunrises
- Bright Skies with Shadowed Landscapes (mountain valleys, hills, or objects that cast shadows)
- Storm Clouds with Patches of Bright Light and patches of shadow beneath
In other words if you look at a scene and snap a picture and there is a huge difference (colors washed out, details totally lost etc) then it is likely a job for a graduated neutral density filter. There are exceptions to this rule and I highly encourage everyone to take there graduated neutral density filter and shoot a test shot in any and every conceivable lighting situation so they know how it will react. There may well come a time where you are looking for a certain thing and your graduated neutral density filter might be the filter that will give that to you even if it is not a time or situation where it normally would call for the use of such an extreme filter.
Remember this in the back of your mind. Your eyes are completely capable of adjusting too many different shades and areas of contrast at the same time. Your camera is not. Therefore the graduated neutral density filter takes over and tries to duplicate what the human eye does so that you can capture what you are seeing. The human eye is capable of adjusting to various ISO settings from one point to another but a camera can not that is where a graduated neutral density filter comes in to play.
1. Sunsets and Sunrises
Taken in the Annapurna Himalaya, Nepal 2012
In the image above, I used a two stop hard grad stacked with a 2 stop soft grad. The lighting conditions in the high Himalayas, with the massive mountain valleys and brilliant skies, is extremely contrasting. There were something like 4 or so stops of light difference between the sunrise over the mountain tips and the shadowed valley below.
The prime usage of grad filters is when there is a large contrast in lighting between parts of the frame especially between the sky and the ground. These extreme variations in lighting differences can occur in a number of situations — cloudy days, mountains during a sunny day casting shadows beneath, valleys, and of course sunset and sunrises.
Sunsets and Sunrises are IDEAL times to use grad filters because the sky is far brighter than the foreground during this time — usually between 2 to 4 stops difference. Without grad filters, you either get a brilliant sky and silhouetted landscape below or a washed out sky and an properly exposed foreground.
The two options of fixing this are to either shoot multiple exposure for an HDR, which can give you an over-processed look or to fix the exposure in-camera with Grad Filters. Between the two, I always opt for grad filters. You can even get a better, more realistic image by using Grad filters then doing HDR on those series of images as well.
2. You Want Dramatic Clouds with a Moody, Dark Atmosphere
Another useful application for grad filters is to use them during a cloudy day — even if there is not a light. This has the effect to really pull out the clouds and create a moody, atmospheric picture.
I find the effect useful during storms, mist, and locations (like Scotland) where there are valleys and lots dark clouds spilling over some of the valleys — especially if they cast some shadows on the landscape below.
Just remember, sunsets/sunrises are not the only time you need grad filters — you can use them even when it’s stormy and cloudy with the sun hidden behind the clouds.
3. You Want More Saturation in the Sky
Hiking the Annapurna, Nepal
Technically, there was enough even lighting on the ground and mountain valleys that I did not need to use a grad filter, but I found that adding a 2 stop soft grad to the scene helped pull out some of the cloud detail a bit more. It’s a judgment call whether you want to use grad filters in situations like this, but generally I find the effect brings a stronger picture.
Here’s another example — in this case there were NO clouds — where I used a grad with the sky to bring out an even deeper blue. Again, with just a circular polarizer at this altitude (4000 meters), the sky would still be a nice azure blue, but again, using a softer grad, especially on the white mountains which sometimes end up overexposed because they reflect so much light, helps give a better picture.
Life at 4500 meters, Nepal
If there’s a situation where you have a real dynamic sky, you can pull out your grad filters to bring out the sky details. This really can help turn a good sky into an awesome one, especially if you have an interesting foreground and point of interest. Unlike the other conditions, you can get by WITHOUT grad filters because there is even lighting in the scene already with little or no shadows. But using grad filters helps pull out a more powerful sky.
4. You Are Shooting in Raw and Want More Post Processing Flexibility
Another time where using a graduated neutral density filter is almost a necessity is when you are capturing a shot in the RAW format that most of the higher end digital camera use. That is because it will allow the sensor to grab onto every detail that is in front of it and store it where you can get it into the computer and do your post shooting magic. The nice thing here is that if you try a shot with and then one immediately after it without the graduated neutral density filter you will see how much extra detail is actually there that you would have normally missed and that will be, as they say, the proof in the pudding.
Sunset in the Himalaya
In the above image, I was able to play around with the exposure setting slightly because I shot in RAW and with grad filters (3 stop soft). There was a lot of contrasting lighting going on. Yes, you can just opt to shoot at multiple exposures for an HDR, but remember that if you are shooting at +2 or -2 exposure stops, there is a loss of detail between exposures. You can get a better exposed image (or series of images) if you equalize the exposure IN camera with grad filters first.
How Graduated Neutral Density Filters Work
Unless you are an avid photographer you may have only heard casual mention of the graduated neutral density filter. They have kind of been kept the deep dark secret of the professional photographer.
To make the explanation as simple as is possible, the graduated neutral density filter is used to control light that is too bright in one part of the picture. A good example would be shooting a scene with some bright sky in it. In fact most real pros will not walk out of the studio without having their graduated neutral density filter and a polarizing filter in their bag. These two filters allow you to take advantage of situations where the light would otherwise not allow you to take a photograph.
The great thing here is that when you put the filter on and look in the viewfinder, you immediately know what the effect is and whether or not it is going to give you what you are after. As you love the graduated neutral density filter or the polarizing filter you see the changes in real time and when you find the sweet spot that will give you exactly what you want to capture.
As you look at most of the graduated neutral density filters on the market you will see that it is a little gray across the top of the filter. In pother words they will be gray across the top and clear at the bottom with graduated variances between the two. Somewhat like the little area across your car windshield where there is a darkened area on top to cut down on the amount of incoming sun and then it is clear on the bottom.
The graduated neutral density filters work by rotating them. You will continue to turn them until the gray section actually covers the portion of the image that needs to be darkened to help it match the rest of the image. The key to using it effectively is to make sure that the clear section is over the area of the scene that is exactly where it needs to be and then the gray portion is allowed to tame the overly bright area and bring it in line with the rest of the scene giving you the perfect over all exposure.
What tends to scare a lot of new comers away from actually using this very effective tool is that there are many different types and styles of the graduated neutral density filter on the market and it can be intimidation to those folks that are not photographically adept.
Most of the graduated neutral density filters are not coated in any way. But there are some new ones out there that are coated and what is nice about that is that it tends to help cut down on the numbers of reflections that are captured. It is important for you to keep in mind that you are trying to capture images in less than ideal situations which is why you reached for the graduated neutral density filter in the first place. That means that there is a fair likelihood that you will be dealing with some form of reflection as well.
The problem with the multicoated filters is that they are generally considered to be far more delicate and you need to clean them with a specially designed cloth to keep from damaging the coating that is covering the filter. That doesn’t mean they are going to give you more issues under normal use, it does mean that you need to be more cautious when cleaning them after they get dirty so that you don’t scratch the coating and there by ruin the len
Types of Grad Filters
There are many different strengths or darkness levels on the graduated neutral density filters on the market and you might need several depending on what it is that you typically shoot photos of because this is not necessarily a one size fits all as far as darkness levels.
Screw -On Filters
Of course the most common and usually the cheapest filters are the standard round screw on style that everyone is accustomed to. These are much light the UV Haze or Skylight 1A filters that are typically put on a lens to help protect it.
My take on these as someone who shoots a lot of landscapes is…don’t use them. They are not nearly as flexible as square filters since you can’t adjust the filter vertically to place the gradient over the horizon – you have to move the entire composition by moving the camera. Not a good thing.
The other type of Grad Filter is the far more flexible (and useful) square or rectangular filters made by companies like Hitech, Lee, and Singh-Ray. This type of filter required a special holder that is screwed on to the lens and then a myriad of other filter sheets can be put in various orders by simply sliding them in and out of the holder.
These filters can be slid up and down to reach different effects and thus will tend to give you much more creative control over the shot, albeit they make the camera look a little strange but to some it is a nice and techno look that they like.
Also, you need to keep in mind that the holder will be mounted so that it is a ways away from the end of the lens. If you are using a wide angle lens you are quite likely to end up getting some reflections from the filter back in to the lens and on to the image that you are so carefully attempting to capture. The bad part here is that you are not usually looking for that issue when you snap the photos and you might not even see that problem until you get back to the studio and start looking at them in detail on the large monitor in your editing room. That will either mean a lot of post production work in Photoshop to correct the issue or going out and re-shooting the scene. Neither is a great scenario and in fact re-creating it might actually be impossible depending on what you were shooting. So I personally shy away from that system. Or any system that is remotely similar to it.
About Grad Filter Strengths
The graduated neutral density filters are listed in stops which describe the actual strength of the filter. It typically ranges from 0.3 and go up to around 5.0. In very rare cases you might need a low or a higher density filter but for the most part you can pretty much be happy with one that falls in between 2 and 3 on the stop scale.
The stop is the how much light is reduced from the effect of the graduated neutral density filter that you are using. That might make it a little easier for you to understand what is happening on the filter end of the deal.
There are many varieties in the graduated neutral density filter and the step filter range and so let’s take a little time here and describe what is going on here. It gets more than a little on the confusing side but let’s take a stab at it.
About Types of Grad Filters
There are four types.
1. Hard Edge Grad Filters
This type of graduated neutral density filters has a sharp cut between light and dark. There is no gradual change it goes right from dark to clear. That is great for some special effects but for the most part they are pretty unusable in most common place situations that you might typically use a graduated neutral density filter
2. Soft Edge Grad Filters
This is the most common type of graduated neutral density filter that is on the market and what most people use. They have a gradual change from light to dark so that it is more of a gradual change taking place and as a result.
3. Reverse Grad Filters
These go sharply from clear to dark, and then smoothly back to less dark. I l know that it seems like that might not be the best case scenario but take the time to rationalize it out. These graduated neutral density filters are phenomenal for the use in shooting sunsets because it allows you to have a clear foreground area and then very dark at the sun and less dark as it goes up. This truly allows you to make the light work for you.
4. Other Grad Filter Types
There are curved graduated neutral density filters which are wonderful for shooting hills and mountains because the curve fits them more naturally than a straight line. There are various colors beyond gray which can also be purchased and used.
Tobacco is a very popular choice especially for people doing sunsets or travel shooting while on vacation because it turns everything a rather smoky brownish orange color that just looks great on a sunset. If you look hard enough you can find the graduated neutral density filters in just about any complimentary color out there.
Blues are another one that people use a lot when shooting ocean shots to help enhance the water or even to help make the sky a lit more blue than it truly is.
Choosing the Right Grad Filter for Your Photography?
The first thing to figure out is what filters you really think you need. Look at the type and style of shooting you do and see what will serve you the best. You certainly have no need or desire I am sure to weigh your camera bag down with a bunch of useless filters. Once you have made that decision, it is just a matter of making sure that you have one of each of the appropriate densities in the sizes that will fit all of your lenses. If your lenses all take a 52 mm filter then one of each is great, if you have a couple 52s and a 55 mm then you need two of each, etc.
Glass or plastic graduated neutral density filters?
The other thing to keep in mind is the quality of the filters. Some are made of some pretty good glass and still others are nothing more than a sheet of plastic. Obviously the glass is going to last a lot longer under usage than plastic and will significantly improve the optical quality of the image you shoot.
On the surface you might suggest that it really should not matter a lot if it is plastic or glass. And in theory there is some merit to that. That is until you remember why you are using a graduated neutral density filter in the first place. You will obviously be pointing the camera towards a bright object, such as the sun. That would tend to make me think that any scratches that are on the plastic will show up large and proud in an image that you might capture through it.
The other problem that I can foresee here is that a plastic filter is going to be more susceptible to warping in the heat. In fact even a miniscule change is the flatness of something that you are shooting through can have a very adverse effect on the end resultant photo image.
And of course the coating will make difference on glass filters. If they are uncoated then they will be tougher and easier to clean but will not give you as good of a shot as the harder to clean and more easily scratched multi coated filters.
Keep in mind as well that quality control on these graduated neutral density filters is likely to be low and could vary from sample to sample. This is especially true when you are talking about the plastic filters which very from one batch to the next because of resin dying.
Also the actual color of the tinting might vary and instead of being a true gray it might have just a little orange or magenta in it. The problem with the tinting issue is that you might not even notice it through the lens but once the shot is taken and you view it on your computer it can be quite evident. What that should tell you is that, at the very least – no matter what you settle on your should shoot some test shots and make sure there is nothing there that is going to irritate you before you have anything important that you go to shoot.
What should I look for in a graduated neutral density filter?
The first thing would be the mount. Do you want the screw on circular graduated neutral density filter or the square custom mounted graduated neutral density filter? That is truly one of the big decisions. I think that most folks should opt for the round style because they are smaller and generally tougher made. But that is a personal opinion and something that you certainly are capable of making your mind up about.
The brand is another area that I think you should give some in depth thought about. That has absolutely nothing to do with being stuck up or having to look like you own the best. It has to do with quality control. Some of the no name companies simply do not have the ability to make a good filter. When you look and there are companies selling filter so $5.00 and then some selling neat $100.00. Good sense should tell you that there is no way that there is that large of a spread in the cost of production for the same quality. That should clue you to the fact that more money is more than likely going to mean a better quality product.
Some of the filters that I use personally are from companies like Hoya, Tiffen and even the camera manufacturers themselves like Canon offer lines of filters that are decent. Remember that it is your reputation on every photograph that you take and that should tell you where to shop for the accessories. Spending a little extra money to cover your name is always a good idea.
Some thoughts about graduated neutral density filters
Keep in mind that the graduated neutral density filter is not designed to be put on your lens and left there forever. In fact they are truly only supposed to be used under very extreme situations where you actually need to gain control over a situation to get a usable shot. They are designed to tame a scene that is high in highs and low in lows and make it even out so that the lens of your camera can somewhat accurately capture the image to film or a memory card. In other words only use them as a last resort when all else fails.
You should also remember that you should usually not use a graduated neutral density filter to darken normal daytime skies. That is unless you are looking for a deliberate look that calls for that. As a general rule if you look at a daytime sky it is bright as it is supposed to be. If you use a graduated neutral density filter to darken the sky under normal conditions, you wind up with a sinister, stormy look, but unless that is what you are looking to achieve it will not a better picture.
Another use for a graduated neutral density filter that people often forget about is to lighten a subject inside a room and to deliberately darken a window. That way you can get a much more balanced look to a subject that is standing next to a window where the outside scene is very well lit by sunshine
Keep in mind as well that the lines are pretty clear cut and straight so you will not get a great result if you try and use it on a mountain, like the Rocky Mountains for example will not photograph well or realistically with a graduated neutral density filter.
For the most part you need to do nothing more than to attaché the filter and look through the viewfinder to adjust it you what you are trying to shoot and push the shutter button. All of the cameras on the market today automatically make adjustments for anything that comes between the front of the lens and the actual image sensor. So any changes you make will automatically be reflected in the final photo result.
It’s one of the things that you may not use more than a few times in your lifetime unless you shoot a lot of sunsets but it is one of the most important additions top any camera bag. It is like an American Express Card. You should not leave home without it.
How To Use a GND in the Field
Ladakh, India in 2015 at 3600 meters
I won’t bother talking about the screw-on GND’s. There are far inferior to the square ones.
You have a couple options on how to use your GND:
- Use a Filter Holder System (You can buy a filter holder kit such as the Cokin Z Filter Holder — see my article on Filter Holder Systems)
- Hand Hold Your Filter Over the Lens
- Use putty to ‘stick’ Your GND to your lens for hands free operation.
Ok, here’s How to Use Your Graduate Neutral Density Filter:
1. Decide If You Need a GND
The first step here is to look at your frame and decide IF you need to USE a GND or not. These days, you can opt to use your Auto Bracketing to take multiple exposures for an HDR photo. This is an alternative to using GND’s. However, I feel you still get better images to control the lighting optically rather than using software. You can always still use HDR with your GND images — and chances are you will have better exposures to work with.
2. Decide What Type of GND
Assuming there is contrasting lighting and a GND can be used, you now need to decide WHAT type of GND to use. DO you opt for a hard grad, soft grand, or reverse grad, or stack some combination.
The answer really depends on the lighting situation. Here are some tips that I use to decide:
- Use a Hard Grand When: There is a CLEAR boundary between the sky and the ground such as sunset over water, sunset over plains, or there is a great distance between objects like mountains and building and the foreground, then a Hard Grad is ideal. There reason is that the dark part of the grad can easily cover the lighted part of the sky while the clear part can cover the landscape leading to a very well exposed image.
- Use a Soft Grad When: There objects poking into the sky and no clear boundary between sky and ground then opt for a Soft Grad. Examples would be taking photos of mountains (and the mountains are fairly close to you), pictures of cities with the city line poking into the sky, etc.
- Use a Reverse Grad When: The sun is RIGHT on the horizon and there is a clear boundary between sky and the land then a Reverse Grad is the winner. This situation only occurs when you take a frame of the sea/ocean or the plains during sunset or sunrise.
3. Decide What Strength of GND The Shot Requires
Once you decide what type of GND you need for your shot, you then need to pick out what strength. Remember, each GND is rated by how many fstops they compensate for. A good rule of thumb is that for sunset/sunrise where the sun is nearly at the horizon, a 2 stop GND works. If the sun is not yet at the horizon and very strong with a bright sky and darker landscape, then you’ll want a 3 or 4 stop GND. You can ‘stack’ a couple grands together, either by putting multiple GND’s in your filter holder or by hand holding them against your lens.
4. Compose Your Shot with the GND
How to Hand Hold: Personally, I always hand-hold my GND filters against the lens (I use a tripod). Yes, this may induce a bit of camera shake, but it’s something I live with the the sheer ease of use, quickness, and flexibility. The cost is that well, you may have a tiny bit of shake on your photo (it’s not really noticeable) and your GND’s will wear out sooner than later and may end up with scratches. Note that I still use GND’s covered in scratches that are a few years old and for the most part, unless you are shooting directly into the sun, you don’t notice these scratches in the picture.
How to Use Putty: If you don’t want to hand hold but you want some of the flexibility, then use some sort of putty to stick the GND’s to the lens at the appropriate angle so you are not holding them.
How to Use Filter Holder: Simply shove in your square/retengular filters into the filter holder slots then rotate the filter holder so your GND’s dark part covers the sky while the clear part covers the ground.
Keep in mind you can opt to use use the Filter Holder like the Cokin Z. The issue here is that you can’t use your polarizer if this is the case and since there is a bit of space between each filter in the filter holder (if you stack filters in the holder), you may get some pink tinge in your image.
When you compose your image with the GND’s, you can opt to hold them at certain angles so you blog the sky. For example, sometimes you might want to twist the holder or fitler slightly at an angle to block the sky if you are taking shots of mountains. The idea is to only use the dark parts of the filter on the sky while keeping the clear section over the foreground. Sometimes you get a better image if you rotate the GND’s, especially if there are mountains. You would keep the dark parts over the sky with the clear part over the mountain and the foreground. It doesn’t always work if the landscape does not allow this, but in some cases it will and you get a better image by doing this then if you just put the filter horizontally with the dark part over the sky and mountain.
If you hand hold, try moving the filter up and down a bit so lessen the gradient between sky and ground. It can ensure your image does NOT have a dark band over the tips of mountains.