You do not need an expensive macro lens to start photographing small subjects. Extension tubes, close-up filters and even reversing an ordinary lens can produce impressive close-ups. Dedicated macro lenses offer convenience and quality, and specialised lenses reach magnifications far beyond life-size. This lesson compares the main options, gives simple ways to estimate the magnification each provides, and explains the trade-offs so you can choose the right tool for your subjects and budget.
Why there are many methods
To magnify a subject, a lens must focus closer than normal, either by moving its optics further from the sensor or by adding extra lens power. Different tools do this in different ways, each with its own effect on quality, working distance, light and convenience. Magnification and working distance were explained in magnification and working distance.
Dedicated macro lenses
A macro lens, introduced in macro, fisheye and specialty lenses, is designed to focus from infinity down to (usually) 1:1, with high sharpness and flat-field performance close up. Advantages include autofocus, stabilization on many models, consistent quality and the ability to switch instantly between distant and close subjects. Most reach 1:1; some newer designs go slightly beyond.
Extension tubes
Extension tubes are hollow rings, with no glass, placed between the camera and lens. They move the lens further from the sensor, allowing closer focus. A useful approximation at infinity focus:
| Lens | Extension | Approximate added magnification |
|---|---|---|
| 50mm | 25 mm | About 0.5× |
| 50mm | 50 mm | About 1× |
| 100mm | 25 mm | About 0.25× |
- Advantages: affordable, no extra glass, work with many lenses; electronic versions keep autofocus and aperture control.
- Disadvantages: you lose infinity focus while they are attached, lose light, and need more extension for longer lenses.
Close-up filters (diopters)
Close-up filters screw onto the front of a lens like a filter and add magnifying power, measured in diopters (+1, +2, +4 and so on). At infinity focus, a useful approximation is:
| Lens | Close-up filter | Approximate magnification at infinity focus |
|---|---|---|
| 100mm | +2 | About 0.2× |
| 100mm | +4 | About 0.4× |
| 200mm | +4 | About 0.8× |
- Advantages: light, quick to fit, no light loss, work especially well on telephoto zooms.
- Disadvantages: single-element filters can soften edges and add color fringing; two-element (achromatic) types are much better.
Reversed lenses and bellows
| Method | How it works | Notes |
|---|---|---|
| Reversed lens | Mount an ordinary lens backwards with an adapter | High magnification cheaply, especially with wide lenses; manual control; very short working distance |
| Stacked lenses | Reverse one lens onto the front of another | High magnification; vignetting and handling challenges |
| Bellows | An adjustable extension that can be set precisely | Flexible, high magnification; best for studio and technical work |
High-magnification macro lenses
Some specialised lenses focus only at very close distances and provide magnifications from about 1× up to 5× or more, for subjects such as insect eyes and tiny components. They usually have very short working distances, need strong light, and often need focus stacking, as in focus stacking. Microscope objectives adapted to cameras go further still, used mainly in scientific work.
Comparing the options
| Method | Cost | Image quality | Convenience | Best for |
|---|---|---|---|---|
| Macro lens | Medium to high | Excellent | Very good | Most macro work |
| Extension tubes | Low | Depends on the lens | Good | Budget macro with existing lenses |
| Close-up filters | Low to medium | Good with achromatic types | Very good | Travel, telephoto close-ups |
| Reversed lens | Very low | Can be very good | Low | Experiments, high magnification on a budget |
| Bellows | Medium | Very good | Low | Studio and technical work |
| High-magnification lens | High | Excellent | Specialised | Extreme macro |
Common mistakes
- Cheap single-element diopters on demanding work: soft edges and fringing.
- Expecting tubes to work at infinity: they only allow close focus.
- Extreme magnification as a first step: very hard technique; start near 1:1.
- Forgetting light loss with tubes and bellows: slow shutter speeds.
How professionals choose
Most professionals rely on a dedicated macro lens for everyday work, add tubes or an achromatic close-up filter when they need a little extra, and use specialised high-magnification lenses, bellows or microscope objectives for extreme or scientific work. They choose by required magnification, working distance and quality, not by price alone.
Practical examples
Starting macro on a budget
- Situation
- You own a 50mm lens and want to try close-ups of flowers.
- What to do
- You buy a set of electronic extension tubes and use 25 mm of extension.
- Why it works
- 25 mm on a 50mm lens adds about 0.5× magnification without extra glass.
- Result
- Detailed flower close-ups for a small cost.
Butterflies on a hike
- Situation
- You carry a 70–200mm zoom and want close-ups of butterflies without extra weight.
- What to do
- You add a +2 achromatic close-up filter.
- Why it works
- At 200mm, a +2 filter gives about 0.4× magnification with plenty of working distance.
- Result
- Sharp butterfly portraits from a comfortable distance.
Key points
- Macro lenses offer the best convenience and quality, usually to 1:1.
- Extension tubes add about extension ÷ focal length of magnification, with light loss and no infinity focus.
- Close-up filters add about focal length × diopters ÷ 1000 of magnification; achromatic types are best.
- Reversed lenses and bellows give high magnification cheaply or flexibly, with handling challenges.
- High-magnification lenses reach 1×–5× or more for extreme macro.
Frequently asked questions
Are extension tubes as good as a macro lens?
What are close-up filters?
How much magnification do extension tubes give?
What is a reversed lens macro?
Conclusion
There are many ways to magnify small subjects: macro lenses, extension tubes, close-up filters, reversed lenses, bellows and specialised high-magnification lenses. Choose by magnification, working distance, quality and convenience. Next, you will learn how depth of field behaves at high magnification.
Finished reading? Track your progress through Macro and technical.