Two Filters I Won’t Leave Home Without

by Anthony Morganti

In my film days – before there were things called Lightroom and Photoshop, I had a huge bag that was chock full of lens filters. Color correcting filters, star filters, soft focus filters, vignette filters and several different colors of graduated filters. Today, I’ve replaced all of those filters with Lightroom and Photoshop.

It’s amazing what can be done in post nowadays, but today, there still are a couple filters that go with me everywhere because they can’t be replaced by software — that would be a circular polarizer and a 10 Stop ND filter.

Circular Polarizer

Circular Polarizer

A Circular Polarizer lets in 2 stops less of light

Back in the day when, like Billy Joel, I wore a younger man’s clothes, one of the first filters I purchased was a circular polarizer. I loved how I could deepen the blue skies of my landscape photos and remove the glare and reflection from windows, eyeglasses and water. In fact, I believe there was a time when I left the polarizer on my lens all the time.

Today, I use the polarizer a bit differently. I still use it to remove glare and reflections but the main reason I’m twisting one on is to reduce the amount of light making it to my camera’s sensor.

I do this so that I can use a slower shutter speed. I want a slow shutter speed to do one of two things:

I Want To Blur Water

Akron Falls

A 2 second Shutter Speed Blurred The Flow Of This Waterfall Nicely

The classic shot of a waterfall or running water is when their flow is blurred silky smooth. Very simply, this is done by using a slow shutter speed. Depending on the flow of the water, the effective shutter speed may vary from ½ of a second to several seconds. On bright days this is impossible to achieve.

One side-effect of using a circular polarizer is that it blocks some of the light, allowing a lesser amount to pass through the lens to the camera’s sensor. Most polarizers let in 2 stops less of light.

This can be ideal when you need to achieve that slow shutter speed required to blur the flow of water. Generally, the longer the shutter speed, the more the water will be blurred.

If you can’t get your shutter speed at or below ½ of a second because it’s too bright, try using a polarizer.

I Want To Blur Motion

The other reason that you may desire a longer shutter speed is to blur motion. Again, if the environment is too bright, this might be difficult to achieve unless you attach a circular polarizer.

Lighthouse Bell

I wanted a slow enough shutter speed to express the motion of the geese in this shot

Blurring motion can be done for artistic reasons but I tend to use it when I want to show that something is in motion.

For example, when I’m photographing a vehicle such as a car or a bicycle, I want the  viewer to realize that the tires are spinning. I’ll use a slow enough shutter speed to make sure that the circular motion of the tire is recorded by the sensor. If it’s very bright out, I may not be able to record the blurred motion the way I wish. In those cases, I’ll twist up a polarizer so I can shoot at least two stops slower.

Okay, the circular polarizer will deepen colors, remove glare and allow you to shoot at least two stops slower. What other lens could I possibly need beside the polarizer?

10 Stop ND Filter

10 Stop Neutral Density Filter

10 Stop Neutral Density Filter

At times, you may want the water silky smooth. Other times you’ll want is smooth as glass. This is when the 10 Stop ND filter comes into play.

An exposure that normally would be 1/60th of a second would be 15 seconds if you use an ND Filter. An exposure that long smooths out the tiniest ripple and makes the water look like a mirror beautifully reflecting everything above it.

The Lonely Pier

I used a 10 Stop ND Filter for this shot so I could get a 20 second exposure. The long exposure smooth the water to the point that it was like glass

Quality ND filters can be expensive. I recommend that you don’t settle for a cheaper filter because the cheaper ones tend to transfer an uneven color cast on the scene that is nearly impossible to get rid of in post. So, save until you can afford a better quality ND Filter. Also, consider getting a square filter that mounts into a holder. Getting this type of filter allows you to use it on multiple lenses of varying diameters. All you’ll need to move it from lens to lens is a relatively inexpensive mounting ring that matches the diameter of your lens.

The Lee Big Stopper is a square 10 Stop ND filter

The Lee Big Stopper is a square 10 Stop ND filter

So, that’s the two filters that I always carry with me. What filter can’t you leave home without?