When I purchased my first Neutral Density Filters several years ago and started experimenting with Long Exposure Photography, I became fascinated by the magical effects created with shutter speeds of 10, 30, 100 seconds or more.
However, there was one particular problem that regularly occurred: an unwanted purple color/haze was covering parts of the image. It would become so visible and distracting that I had to delete many good images.
After many online searches and discussions with more experienced photographers, I learned that this is a common issue with Long Exposure Photography and is caused by light leaks.
Luckily, there’s an easy fix: cover the viewfinder.
Note: this tip is NOT relevant for those using mirrorless systems.
When to Cover the Viewfinder for Long Exposure Photography
Light leaks normally don’t occur during regular exposures but when using a slow shutter speed, it’s a problem that most encounter regardless of the camera’s quality.
There’s more time for even a small leak to create a strong artifact in the image when the shutter is open for a longer period of time. A normal exposure typically only lasts for a fraction of a second, which isn’t enough time for the leak to affect the image.
So, when do you need to cover the viewfinder?
Exactly when light leaks become visible depends on the scenario but I’ve made it a habit to always cover the viewfinder when placing the camera on a tripod. That means I’m using Live View to compose my images. Another option is to compose the image through the viewfinder and cover it up before taking the shot.
It’s advisable to cover the viewfinder even when shooting at just a few seconds but at the very least, cover it for exposures of 30 seconds or more to avoid interference.
Keep in mind that having a light source (such as street lights) behind you will result in more visible light leaks.
How to Cover the Viewfinder
Some cameras come with a built-in cover made for this exact purpose but if yours doesn’t, here are a few common workarounds:
- Use Gaffer Tape (the best and most common choice)
- Cover the viewfinder with a microfiber cloth
- Place your thumb in front of it (not recommended for longer exposures)
- Use a piece of cardboard
- Purchase a custom viewfinder cap
Which method you choose to use isn’t crucial: just make sure the entire viewfinder is covered properly and no light is leaking through your cover.
Did you enjoy this quick tip? Then be sure to have a look at the Quick Tip Thursday tag where you’ll find new quick tips every week! You might also enjoy your best-selling eBook The Ultimate Guide to Long Exposure Photography.