Finally, macro extension rings with electronic contacts are available at a low price. They are marketed as Meike, Skyblue, Neewer, and probably more names, and one pack includes two rings: One 10mm thick, and one 16mm thick. My rings look like this:
The Micro Four Thirds version of the macro rings is labelled "MK-P-AF3B". When separated, they look like this:
The first impression is that the macro rings look a bit cheap. The mounts appear to be some black nylon-like plastic, and the tubes are unexpectedly light. When mounting them on the camera, they fit somewhat looser than most lenses do. However, they still appear sturdy enough, and I am not worried using them with a large lens like the Lumix G 100-300mm f/4-5.6.
Since the rings transfer the electronic signals between the camera and lens, the camera can control the lens as usual. This means the focus, the aperture, power zoom, optical image stabilization (OIS), and so on. The camera can also identify which lens is mounted, which can be a disadvantage. I'll get back to that, but you can skip to the section "Chromatic Aberrations" if you are impatient.
The rings go between the camera and the lens. They mount on the camera just like any lens, and you can decide yourself if you want to use only one of the rings, or both, with extensions of 10mm, 16mm and 26mm possible. As a general rule, you need more extension for longer lenses. So, if you use a wide angle lens, use the smallest extension, 10mm. For a tele lens, use 26mm.
While these rings will fit any lens, they don't make sense for the widest lenses. For example, if you put the 10mm extension ring between the camera and the Lumix G 8mm f/3.5 fisheye lens, you will find that pretty much nothing is in focus. But the extension ring is hardly needed for that lens. It can focus down to objects nearly touching the front lens element.
How to best use these rings depend on what you want to photograph. But generally speaking, if you want a large working distance, the distance between the subject and the front lens element, then go for a long lens. You can use a tele zoom lens in the longest position, for example. This can be good for photographing insects which are shy and tend to scram if you put a lens in their face.
On the other hand, if you photograph static items at a close range, then you can use a normal kit zoom or a short prime lens, but with a shorter extension.
In theory, you get the most magnification by combining a short lens with a long extension. However, the focus distance becomes short as well, in many cases too short to be usable.
In the following video, I demonstrate how to mount the rings between the Panasonic GH3 camera and the Lumix X 45-175mm f/4-5.6 tele zoom lens. There is also a demonstration of how the autofocus works, and some example videos of bees:
Here are just the bees, without the introduction:
I made the videos by setting up the camera on a tripod with the Lumix X 45-175mm lens at 175mm, and the full 26mm macro rings. I kept a distance of about 0.8 meters from the bees. When I saw a bee landing on a flower, I pointed the camera towards the flower, and locked the ball head. Then I focused using the centre spot focus mode, and initiated the video recording.
This gave me a very high success rate. Making the macro videos this way was very easy, and fun!
Magnification and working distance
By combining various lenses with the macro rings, you can achieve various magnifications and focus distances. Here's a table that sums up some of the possibilities:
|Lens||Focal length||Extension||Focus distance||Working distance||Magnification|
|Lumix G 45-200mm||45mm||None||0.73m-∞|
|Lumix G 45-200mm||200mm||None||0.96m-∞||Max 1:5.3|
|Lumix G 45-200mm||45mm||26mm||0.215m-0.240m||0.065m-0.09m||Max 1:1.45|
|Lumix G 45-200mm||200mm||26mm||0.66m-2m||Max 1:2.49|
|Lumix G 12-42mm||42mm||None||0.40m||Max 1:6.25|
|Lumix G 12-42mm||42mm||10mm||0.035m-0.071m||1:2.6-1:8.7|
|Lumix G 12-42mm||42mm||26mm||0.014m-0.026m||1:0.81-1:1.5|
|Leica DG 45mm 1:1 macro||45mm||None||0.15m-∞||0.06m-∞||Max 1:1|
|Leica DG 45mm 1:1 macro||45mm||16mm||0.05m-0.15m||1:0.64-1:2.95|
|Leica DG 45mm 1:1 macro||45mm||26mm||0.047m-0.095m||1:0.55-1:1.734|
|Lumix X 12-35mm f/2.8||35mm||10mm||0.01m-0.10m||Not measured|
|Lumix X 12-35mm f/2.8||35mm||16mm||0m-0.02m||Not measured|
|Lumix 100-300mm||300mm||None||1.3m-∞||Max 1:4.8|
|Lumix 14-140mm||140mm||26mm||0.15m||Max 1:1.8|
How to read this table: Take the Lumix G 45-200mm at 45mm with 26mm extension as an example. Using this combination, you can only focus from 0.215m-0.240m, which is a quite narrow range. Within this range, you can use autofocus. Keep in mind that the focus distance is measured from the sensor to the subject. The working distance, though, is measured from the front of the lens to the subject. The lens plus the 26mm extension plus the register distance is 0.15m, which explains the difference between the focus distance range, and the working distance range.
Still using the same lens and extension combination, you can achieve the largest magnification (at the closest focus distance) of 1:1.45. This corresponds to photographing an object 1.45 times the size of the sensor, i.e., 25mm x 19mm.
Using the Lumix G 12-42mm at 42mm, and with 26mm extension, you can only use a working distance between 0.014m and 0.026m, i.e., both less than one inch. Outside this, you can never focus at all, using this combination. Hence, you need to remove the lens hood, to be able to put the subject close enough.
In this setup, you can photograph items sized 14mm x 11mm, i.e., a very large magnification. However, this magnification is doable with a working distance of 0.014m, about half an inch. Autofocus still works, but only within the range given in the table.
As you can see in the table, the most useful combination for insect photography is the Lumix G 45-200mm f/4-5.6 in the upper part of the zoom range, and with 26mm extension. This gives you a generous working distance of about two feet, and a good magnification rate of 1:2.49.
The extension rings are also useful for nearly doubling the magnification rate of the Panasonic-Leica DG 45mm 1:1 macro lens, while retaining a good working distance of about two inches.
I would not recommend using the macro rings with the Lumix X 12-35mm f/2.8 premium standard zoom lens. Even when using the smallest extension ring only, 10mm, the working distance becomes very small. I did not measure the magnification rate at these distances, but it was not very impressive. On the positive side, I did not notice any CA effects.
All these images were taken on freehand, without the support of a tripod.
Lumix G 45-200mm at 200mm, f/11, 1/400s, ISO 640, and 26mm macro extension:
and a 100% crop:
Lumix G 12-42mm at 42mm, f/10, 1/80s, ISO 640, and 26mm macro extension:
and a 100% crop:
Lumix G 12-42mm at 42mm, f/10, 1/200s, ISO 200, and 16mm macro extension:
and a 100% crop:
Panasonic-Leica DG 45mm 1:1 macro with 26mm extension, at 1:0.55 magnification rate. f/10, 1/100s, ISO 800:
and a 100% crop:
Chromatic Aberrations (CA)
When using a Panasonic camera, in combination with some Panasonic lenses, the camera will apply image processing to correct for Chromatic Aberrations (CA). This is a design choice done by Panasonic, which I think makes a lot of sense. It (potentially) keeps the lenses more compact, and focuses on optically correcting what cannot be corrected in post processing, while leaving geometric distortions and CAs to be adjusted by the camera.
In this application, however, we are adjusting the optical formula of the lens, by inserting the macro tubes in front of the camera. So when the camera recognizes what lens is connected, it will try to apply the adjustments it thinks are necessary to get the best image quality. However, it is not aware that the optical formula has changed, and the image processing may very well make the image worse.
I can illustrate this by showing the same image taken with the Lumix X 45-175mm f/4-5.6 and the Lumix G 45-200mm f/4-5.6, both with the full 26mm macro extension mounted:
|Lumix X 45-175mm @ 175mm f/11||Lumix G 45-200mm @ 175mm f/11|
Enlarging the top left corner makes the differences very clear:
When seeing this, one could conclude that the Lumix X 45-175mm f/4-5.6 is a poor lens, and should be avoided at all cost. However, that is the wrong conclusion. The CAs above were not generated by the lens, they were generated by the camera! When the camera adjusted for the CAs of the lens, it did not know that we were changing the optical properties by adding a macro tube. So rather than fixing a CA issue, it created the CAs.
It is possible to adjust this back to normal using image processing. I used the Chromatic Aberrations filter in The Gimp, and set Lateral Blue to 10 and Lateral Red to -10, giving this result (from the top left corner):
It's not perfect, but it is a lot better. Not a lot of people photograph barcode stickers, though. Here is a real life example done using the Lumix X 45-175mm at 175mm, f/10:
You can see that there are some CA artefacts, especially in the top left corner. Applying the CA filter in The Gimp solves most of it:
Due to the CAs, it is probably best to not use the Lumix X 45-175mm f/4-5.6 together with the macro rings. A "low tech" lens like the Lumix G 45-200mm f4-5.6 gives better results. Olympus does not apply any CA correction in post processing, so the Olympus 40-150mm f/4-5.6 should also be safe in this respect.
I don't think the Lumix X 45-175mm f/4-5.6 is a poor lens due to these results. For general tele use, I think it is brilliant, and it is my favourite lens.
Issue with the glossy insides of the rings?
Some have raise the issue of the insides of the rings: The surface is glossy, which can potentially reflect stray light, causing a loss of contrast in the image. I have tested to sand down the inside of the ring, and take an example image before and after. I found that the resulting images were very similar.
My conclusion is: The lack of contrast due to the glossy macro ring insides is not a big issue. And if you are worried about it, it's a simple matter to fix it by sanding the insides a bit. Just make sure you don't get any plastic dust into the sensor. Read more about it here.
If you prefer to buy a set of rings which don't have this problem in the first place, then the good news is that Kenko is producing some which have a proper matte, ribbed surface inside the rings. They are a bit more expensive, though.
The Meike/Skyblue/Neewer macro, are cheap, light, and appear solidly made. They are easy to bring along, to have a macro option easily available. They can be combined with almost any Micro Four Thirds lens, and enable autofocus, aperture operation, and EXIF information. Ideally, you can combine them with a tele zoom lens, for example the Lumix G 45-200mm f4-5.6, or the Olympus 40-150mm f/4-5.6 if you have an Olympus camera.
Using the macro rings with a lens that requires a lot of Chromatic Aberrations (CA) correction can yield poor results in the corners, for example the Lumix X 45-175mm f/4-5.6.
The macro rings are a good addition to the equipment list for anyone who is curious about macro photography. For protection, you could add a rear lens cap and a body cap, which you can put on the macro rings when not in use.
The rings are made of mostly plastic. I'm fine with that. If you prefer a metal alternative, there are more pricey alternatives available with metal mounts.
Out of the low cost macro possibilities I have tested, I definitively like this one the most. It is the only macro solution which has allowed me to make a video of bees easily.