Creating super long exposures during the day requires the use of neutral density filters capable of blocking a lot of light. During the brightest parts of the day the sunlight is very intense, with exposure times often around 1/500th secs and faster being required to expose correctly. A NiSi 15 Stop ND filter – also known as the “Super Stopper” – will help achieve the artistic shutter speeds required for extreme long exposure cloud movement and silky smooth water when shooting during the day. The middle of the day is often seen as unsuitable for shooting long exposure landscape images due to the bright, harsh and often contrasty light and shadows that are produced when the sun is higher in the sky. By using a 15 stop ND filter you can introduce movement and softness into otherwise harsh lighting conditions. Cloud movement can be captured across a longer period of time. Water can be smoothed creating a dreamy, artistic effect in your images. A 15 stop ND filter can help you to be creative at a time of the day when many landscape photographers would not plan to be out shooting, and create artistic images out of what is often considered to be less than ideal light for landscape photography.
What is a 15 stop neutral density filter?
Neutral density filters are designed to allow a reduced amount of light to enter your lens and hit your camera sensor. Light is calculated in “stops” – with a single stop of light reduction doubling your shutter speed. Each additional stop of light being reduced would incrementally double your shutter speed. A 15 stop ND filter, also known as a ND32000 allows only 1/32,000th of the available light to enter the camera, allowing for extremely long shutter speeds in even the brightest of lighting situations like the middle of the day. Because of their extreme density, 15 stop ND filters are best used in very bright conditions. Attempting to use one during sunrise or sunset will require extremely long shutter speeds across a period of time when light is shifting quickly. It is not uncommon to shoot exposures of between 1 second and upwards of 2 or 3 minutes during these times with no filters, or with less dense filters such as a 6 stop or 10 stop ND attached. If just a 1 second exposure time is required without filters, by using a 15 stop ND filter your exposure time would extend out to 9 hours, 6 minutes and 8 seconds! This is quite a long time… That is why 15 stop ND filters are best used in much brighter parts of the day when the sun is high and the light is at its most intense. If a shutter speed of around 1/100th seconds is required without ND filters, a shutter speed of 5 minutes and 27 seconds is what would be required when using a 15 stop ND. These longer shutter speeds will allow you to capture cloud movement and extremely smooth, silky water effects. Something to be aware of when using 15 stop ND filters is they are best used in consistent lighting conditions where light is not shifting during the long exposures. Any changes in lighting conditions can easily lead to exposure issues if you are not adjusting your exposure times for the shifting light.
NiSi 15 stop ND filters are available for our square filters systems in 75mm, 100mm and 150mm sizes and can be stacked with other filters such as graduated ND filters. Our NiSi 15 stop circular ND filters come in a range of sizes from 67mm to 95mm for lenses with standard screw on filter threads. All of our 15 stop neutral density filters are made from the highest quality optical glass ensuring consistent and uniform light transmission across the entire filter.
How do you use a 15 stop neutral density filter?
A NiSi 15 stop ND filter is an extremely dark piece of optical glass which you will not be able to see through with your eyes. Your camera will also not be able to expose for the scene with the filter attached to the camera. This means there will be a process involved in setting up, composing your scene, calculating your desired exposure times and then shooting! Let’s take a look at the steps you should take when using a 15 stop ND filter to capture your images.
Step 1 – Setup camera on tripod and compose your scene
Composing your scene will need to be done prior to attaching a 15 stop ND filter to your lens. Because of the need to shoot very long exposure times, a sturdy tripod will nee to be used to hold the camera and lens. You will not be able to see through the 15 stop ND filter once it is attached to your lens, so ensure you have composed your scene exactly how you like it. It is very important to ensure once you have focussed your lens correctly that you shift into manual focus to lock it before attaching your 15 stop ND filter. Your cameras autofocus will not work once the filter is attached, and you will need to remove the filter to refocus your lens.
Step 2 – Calculate your base exposure time without any neutral density filters
Once you have set your camera up on the tripod and composed your scene, using full manual mode get your exposure settings correct. Using either centre weighted or evaluative metering, get your exposure settings dialled in correctly to be +/- 0EV for the darkest parts of your scene. We will use the following settings as the example for the rest of this article – Shutter speed : 1/250th secsAperture : f / 8ISO: 100Mode : Manual