What kind of lens to photograph a 1 mm object?

Question

I want to photograph an one mm (or slightly less) object. I have a Canon EOS 80D. What lens should I use, or is there any other way to accomplish this?

Answer 1

One cheap option is that you buy a reverse lens adapter.

Of course, you need to take care so you do not let dust inside your camera or let the lens get scratched.

You can also increase the magnification by adding extension tubes.

A cheaper option is using a camera cap as an adapter. If you want a DIY option, for example adding some cardboard extension tube, I recommend that you only use electrical insulating tape. This is elastic and gives you a better grip on the irregular shapes and sizes of the lenses and does not leave residues when removing it.

You will need enough light, so you probably need to use a flash or shoot close to a sun-lighted window. This is especially true if you close your diaphragm to increase the depth of field (But you need a special adapter for that because a kit lens will stay open at max aperture)

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This question additionally has one more variable. Can you crop the resulting image?

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Here are some tests. Excuse the lack of color calibration.

A reversed lens on extension tubes

I used an old manual Prime lens 50mm f1.8 with an aperture of f8. The camera mounted on a tripod looking down and I used a flash to reduce the motion blur produced by the same camera while moving the mirror.

The lens was reversed with some extension tubes of only 7.5 cm.

The camera has a 24Mpx DX sensor.

The focus was using the live view and moving the pedestal up and down.

The first image is a close-up of a vernier (precision ruler) to set the scale.

And here are some grains of sugar. Between .5 and 1.5 mm approx. The red rectangle is a simulation of a FullHD Crop.

And here is the real size of that FullHD crop. (You can open it in a new window)

By comparison, here is the cropped (FullHD) image of the kit lens, mounted normally at 55mm the closest possible. I cheated a bit and applied a small sharpening.

So, to update my answer. Depending on the crop you need even using your normal lens could be an option. Using a reversed lens is a good option to experiment with macro photography.

You can try to get one prime lens of let's say 35mm, a reverse ring, and some extension tubes.

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One interesting thing about the reversed lens is that for example using the kit lens at 55mm gives a lot less magnification than using the 18mm side. You probably do not need an extension tube at all at 18mm.

Reversed lens over a telephoto lens

You need to be extra careful with this setup, put your mounted lens on manual focus mode to prevent any damage. Keep the arrangement in a vertical position to prevent any bending, especially on plastic lenses, like the kit lens.

Here are some new tests using a zoom lens in the 200mm range with an old manual 50mm f1.8 lens on top of it.

The new reference photo is on green, and the old one is in red.

The full framing and the reference FullHD Crop.

And the 100% FullHD Crop.

Additional notes. It is really hard to keep something in focus in this macro setting. I used f32 on the mounted lens, and obviously, it got really dark. I used the flash really close to the subject.

Hall of shame

• My reversed Kit lens got really blurry images using it on the extension tubes. Also, it is hard to set up because the zoom and the focus ring (which should be in manual mode to avoid messing it up) is very loose.

Resampled but no crop.

At 18 mm

At 24mm

• I tried a realllllly long cardboard as an extension tube (70cm), but it presented a really dumb problem. As the image projected is very dull, and a lot of the light is projected into the tube's walls it reflects the light even it was black cardboard. It needs to be painted with really matt paint. That is why I only used at the end the extension tubes that have a special roughness. This is so shameful that is a shame to put it in the hall of shame.

Answer 2

Most kit lenses have only a maximum magnification of 1:3 or 1/3 life size on the image sensor.

Dedicated "Macro" lenses have a maximum magnification of 1:1 or "Life Size" on the image sensor.

Specialized Marco lenses like the Canon MP-E 65mm 1-5x Macro Lens have a maximum magnification of 5:1 or 5 times "Life Size" on the image sensor.

At 5x magnification the depth of field is VERY narrow. Unless you are photographing a flat subject, you will need to take multiple images and use "Focus Stacking" software to get the entire subject in focus.

For more information see: How do zoom, magnification, and focal length relate?

Your Canon 80D has a 22.5mm x 15mm image sensor and here is an approximation of what a 1mm subject might look like in your photos at various magnifications:

Answer 3

To image a 1mm object, you will need a lash-up that will deliver a magnified view. We are talking about perhaps a magnification of 10X. To accomplish, you will need to mount a bellows attachment. The idea is somehow to space the lens several focal lengths forward of its normal position. We normally use what are called tubes. Tubes are neat because some of the high-end ones will maintain the electrical connections between lens and camera body. Such a lash-up upholds the automation your camera provides. A bellows attachment severs these connections forcing you to operate totally manually, however it will deliver the needed extra magnification.

Because of the pitfalls of operating manually, I suggest you first try “afocal” photography. You procure a microscope that delivers low power. These are commonly called dissecting microscopes. You place the subject on the microscope stage and focus in at 10X power. Now you substitute your camera for your eye. In other words, you are imaging through the microscope. No accessories or changes to your camera are required. Your camera with its lens will work just fine, and all the camera’s automation will be available to you.

Answer 4

That kind of object size is getting rather small for the standard photography equipment, you'd need a 5-10× magnification to get a decent image. That kind of magnifications has a certain number of difficulties:

• You have very little depth of field, so only a very narrow 'slice' of your subject will be sharp
• Directly related to this is that your focusing will have to be very precise.
• As your lens will be far from your sensor, you will have a lot less light available than you'd expect from your F-stop reading, so you'll get long exposure times.

This website deals with this kind of photography. It shows various techniques and some of the equipment that's used.

Edit: as mentioned by @MichealClark, Canon does make a 1-5× macro lens which gets you to the magnification you'll need. You'll still need some equipment to position your camera precisely relative to your subject, and ideally allow focus stacking. You'll also have to take precautions against vibration, the slightest movement of either camera or subject will be visible in the image.