There is something about long exposure photography that is just, for lack of a better word, appealing. Blurring moving elements (like water, clouds, tourists and moving cars) in your images can create an ethereal or even surreal aesthetic that many photographers, myself included, are drawn to. Formatt-Hitech’s Firecrest 16-stop neutral density filters take long exposure photography to the extreme. By allowing ten-minute exposures in the middle of the day, these filters open up long exposure techniques to normally impossible times. And it does it with fantastic results. In this article, I’ll review the Firecrest 77mm 16-stop Stackable Neutral Density Filter.
What is it?
A neutral density filter is a piece of material (glass or resin in most cases) that you affix to the front of your lens. What they do is cut down the amount of light hitting your sensor, increasing the amount of time you need to expose for. Doing this allows you to get longer exposures than you would normally be able to, making it easy to blur water and clouds in a satisfying way.
Most ND filters come in a range of one to three stops. However, five and ten-stop filters are also very popular amongst landscape photographers. During golden hour and blue hour, when light levels are generally quite low, these strengths of filter make it easy to achieve exposures that last for several seconds.
What a 16-stop filter allows is extremely long exposures even in the brightest of lighting conditions; including midday sun. For example, with a 16-stop filter, an exposure of 1/2000th of a second becomes 30 seconds. In comparison, with a 10-stop filter, that 1/2000th of second exposure becomes 1/2 of a second. You can probably already see the advantage that the denser 16-stop filter provides.
To drive it home, look at the sunny 16 rule, which says that on a bright sunny day, an exposure of f/16 at 1/125th of a second should give you close to a correct exposure (it usually does). With a 10-stop filter, that becomes 8 seconds.
That might be good enough in many cases, but it also won’t completely blur anything other than the fastest moving elements. With 16 stops, that 1/125th of a second becomes 8 minutes and 44 seconds, ensuring anything moving in your frame is either blurred or disappeared.
What is this good for?
Being able to blur details out of clouds and water allows you to remove details that might detract from your subject. This lends itself well to minimalist styles of photography. If that fits your taste, the results can be stunning.
Exposures of this length not only blur moving elements within your frame but can also completely remove other moving things. Boats in rivers, tourists in front of landmarks, and anything else that might move through your frame during the exposure time disappears.
A filter of this strength is also good for things like star trails at night.
Before you consider
The one thing that you need to know before you consider purchasing a filter like this is that you will need some extra equipment you may not already have. A high-quality tripod is an absolute must as you will need to keep your camera absolutely still during the long exposures.
The other thing you need to take into account is some way of controlling your camera. Because many cameras are limited to exposures of 30 seconds, you will need a way to keep the shutter open in bulb mode for the duration of the exposure without touching the camera. There are many options out there, including remotes and cable releases. I used the Pulse time-lapse trigger from Alpine Labs, which lets you control your camera with your phone. There are others available too, like the MIOPS trigger.
An exposure calculator is also an absolute must as you will need to be able to calculate how long your exposures need to be. There are plenty of free options available for both Android and iOS.
After shopping around for a bit, I decided on Formatt-Hitech’s circular screw-in Firecrest 77mm 16-Stop stackable neutral density filter. This filter has a few features that make it stand out.
Since I knew that I would not be using any other filters in conjunction with this one, I wanted a circular screw-in variety. That’s because I thought that the length of the exposures might create the opportunity for light leaks with my normal filter system. I might be wrong on this, but it’s not a chance I wanted to take.
Formatt-Hitech claims their filter is truly neutral (including in the UV and infrared spectrums) and that there are no color casts. This is important to me as my Lee Big Stopper (10-stops) always adds a strong blue cast that is painful to deal with. I won’t go into details about the coatings as you can find them on the product listings.
Does it do the job?
That’s an emphatic “yes” from me. While there are some downsides to the filter, it provides all of the quality you could expect. The few places it does fall short are all easy to overcome and well worth the little effort to do so.
Just as the exposure calculator said, the 16-stops of ND filter provides really long exposures even in daylight. 1/125th of a second becomes nearly nine minutes, while 1/15th of a second becomes nearly one hour and thirteen minutes.
It’s easy enough to attach the filter to the filter thread of your lens. It does require care as it is easy to slip (I’m sure that’s more me than the filter), but with this technique, there’s no reason to go fast anyway.
I won’t say there is no color cast, but they are very minimal if they appear. Comparing shots with and without the filter side by side, it does seem that there is a slight, slight shift towards blue and green. However, I am not sure if that’s an optical illusion. Either way, it’s easy to deal with.
There are some downsides of both the filter and the technique. However, their effects are minimal and easy to overcome.
As mentioned, to get started with this technique, it’s not just the cost of the filter you need to take into account. If you don’t have a good enough tripod or some variety of release to trigger your camera, you will have to shell out for those.
Despite opting for the circular filter to avoid light leaks, they did appear in my images at the left and right of the bottom third of the frame. They were minimal and easy to deal with in post-production, but they are there.
I have done some research, and it seems there’s a chance these leaks are coming from where the lens attaches to the camera body. If that’s the case, you can fix it by covering the join with black material. Formatt-Hitech also sells an accessory that fits around the front of the lens and filter to help prevent light leaks.
Exposure times in low light
When it comes to shooting later in the day when the exposure times get longer, and the light changes rapidly, it’s likely your required exposure time will change partway through your exposure. For example, if your metered exposure when you start is 1/125th (8 minutes and 44 seconds), and the light levels drop to 1/30th (if the sun moves behind a cloud for example) during that exposure, the new time is 36 minutes and 24 seconds. This means that your image will be quite underexposed.
Because of this, I’ve found this technique works better in the middle of the day when light levels are consistent.
Noise and hot pixels
Noise and hot pixels have little to do with the filter itself. Extremely long exposures with digital cameras open you up to problems with noise. The longer your shutter is open, the more noise appears in your frame.
Software is very good at dealing with this, but you do need to be aware of it.
This is especially true if you opt to up your ISO in lower light levels to keep the exposure time in the minutes rather than in the hours.
What I’ve found with this technique is that it works best with direct light on your subject. If the conditions are overcast, or the light is otherwise dull, the long exposure tends to emphasize the flatness of the scene.
Of course, that won’t always be the case and please don’t take that as a rule of any sort, it’s just an observation. If you live somewhere that is sunny and bright most of the time, this won’t pose you much of a problem. However, I live in Yorkshire and overcast days are the rule rather than the exception.
I do not include the price of the Firecrest 77mm 16-Stop Stackable Neutral Density Filter as either a pro or a con. At $125, it’s probably not going to be an impulse buy for most photographers. However, for what it is, what it does, and how well-made it is, it is well worth that price. It’s also roughly the same price as filter offerings from companies like Lee Filters.
In the end, the Firecrest 77mm 16-stop Stackable Neutral Density Filter does exactly what I wanted it to when I bought it, and it does it well. The complications aren’t hard to overcome, and it is well worth the extra effort. At $125, it is well within reach of anyone who wants to have a serious attempt with the techniques it offers.
I also found that I really appreciate the side effects of the technique. Because the exposure times are incredibly long, you can spend a couple of hours on location and come away with only a handful of images. This slow-treacle approach to photography is enjoyable and turns the whole experience into a mindful one.
If you like the effect of streaky clouds and flat water, or you are into minimalist photography, this type of filter may be indispensable for you.
Do you do long exposure photography? Do you use a 16-stop filter? What are your experiences? Share with us in the comments!