Macro on a Budget: Close-Up Filters

Close-up or macro photography is an incredible way to capture the tiny world around us on a super-detailed level. While the dedicated macro lens is still one of the best tools for exploring the world on a miniature scale, there are some very inexpensive ways to jump into macro photography with the lens or lenses you already own—no need for a specialized close-up macro lens. In this article, we will take a closer look (no pun intended) at close-up filters.

Non-product photos © Todd Vorenkamp

All photos taken with FUJIFILM XF 90mm f/2 R LM WR lens and Hoya HMC Close-Up Filter Set II

What Are Close-Up Filters?

Close-up or close-focusing filters are the photographic equivalent of corrective lenses for your eyes. In fact, for those familiar with prescription eyeglasses or contact lenses, you will notice that the strength of close-up photographic filters is labeled the same way—with diopters. “Filter” in this case is a bit of a misnomer because the filter is not doing any filtration of the image; it is simply allowing the lens to have a shorter minimum focus distance (MFD) and, therefore, larger magnification of the subject.

Close-up filters are called “filters” because they attach to your lens by the same method that most photographic filters do—by screwing into the threads at the front of your lens.

Like extension tubes, these filters allow you to achieve closer focus for close-up photographs using your “regular” lenses—no special dedicated macro lenses need to be used. And, yes, you can also use these filters to boost magnification on macro lenses, too!

What Are the Benefits of Close-Up Filters?

Cost and portability are the primary benefits of close-up filters. Because they are like other photo filters, they can be easily transported in your camera bag, backpack, handbag, or even in your pocket. You can venture out on an expedition with only a single lens, come across a tiny photographic detail out in the wild, reach into your pocket, screw the filter on, and get up close and personal with your subject. Remove the filter and press on!

Although there are exceptions, depending on brands, most close-up filters are relatively inexpensive—especially when compared to the cost of a macro lens.

While extension tubes physically change the subject-to-lens distance, effectively reducing the amount of light getting to the sensor, close-up filters do not have the same darkening effect. Their light reduction is negligible—important for handheld macro shooting when fast shutter speeds are needed to prevent subject motion blur or camera shake blur.

What Are the Possible Drawbacks of Close-Up Filters?

Adding more layers of glass between your lens and your subject always degrades the image in some way, and close-up filters are one of these additional surfaces that will exist between the camera and subject. Even the highest quality optics degrade an image in some way, and this fact extends to close-up filters. So, if you are looking for ultimate sharpness and resolution, close-up filters are not for you. Stacking close-up filters for more magnification is something you can do, but remember, you are adding even more glass for light to pass through.

However, my recent experience with close-up filters (see the photos of the nickels, below) saw some really good performance in terms of sharpness with the filters. Also, a lot of macro photography places an emphasis on center sharpness, and having the outer areas of the image fade to a soft blur is often a great aesthetic for many close-up subjects.

One other downside to close-up filters, as with extension tubes, is that you cannot do “regular” photography with them. You put them on when needed and remove them when you are done, meaning you can’t immediately switch between taking close-up shots and distant shots without removing the close-up filters.

Magnification

Close-up filters are measured in diopters, which is a measure of optical power. The higher the number, the more magnification (and the closer you can get to your subject).

If you are into mathematical formulas, feel free to take a deeper dive on the Internet to find the formulas that allow you to calculate the change in minimum focus distance for each diopter. If you are like me, just slap a filter (or filters) on your lens, focus, and make an image!

The simple math we can all take onboard here is that, if you stack a +2-diopter filter with a +4-diopter filter, you get a +6-diopter magnification.

Filter Sizes

As you shop for close-up filters, you will notice that they are available in different sizes. You can get the size appropriate for your specific lens, or, if you want additional compatibility, you can get a larger diameter close-up lens filter or filters and use step-down rings to fit lenses with smaller filter diameters.

The filter size of your lens is usually marked on the lens (or on your UV filter) and is also available in the specifications section of your lens’s page on the B&H Photo site.

Tips for Use

Using a close-up lens filter is quite simple. However, there are some things to keep in mind to help you get the best images possible.

Focus: Your lens’s autofocus might work just fine with close-up filters attached, so don’t be afraid to try it. If you want maximum magnification, you can always focus manually to your minimum focus distance and adjust your subject-to-lens distance. Sometimes, adding focusing gear can help.

Depth of Field: As you increase a lens’s magnification, you shorten its depth of field for a given aperture and focal length. This can be an artistic boon or a detriment to your photograph, depending on your visual goals. This article discusses how do deal with depth of field with close-up photography.

Shutter Speeds: Another side effect of increased magnification is an increased chance of blurring from camera shake. Boost your lighting, shoot in daylight, or adjust your aperture and ISO to keep your shutter speeds fast enough to avoid blur.

Get Some Glasses for Your Lens

Like the extension tube, the close-up filter is a fantastic way to get into macro and close-up photography. There are so many amazing things to see and photograph when you can see the world at a tiny level. Bugs, flowers, sand, and everyday objects all can make compelling close-up subjects for your camera and lens.

In the other articles in this series—Macro on a Budget—we look at additions for your lens, or lenses, that allow you to explore the world up-close: extension tubes, reversing rings, and macro couplers.

Do you have questions about close-up filters? Or have you used them in the past and have some tips to share from your experiences? Let us know in the Comments section, below.