Perhaps the most mysterious of all macro photography methods is the use of microfilm lenses. We can find almost no information about these lenses. If we have a microfilm lens, it could be a piece of junk or a gem!
If you haven’t already read it, I suggest you take a look at the first post on this topic before continuing. Some basic information is there: Macrophotography with a microfilm lens
Microfilm
Microfilm is an archiving method. Despite 100 years of use and the existence of computers, it is still popular. Because it takes up little space and is very durable. A microfilm has a structure that cannot be affected by fire. It lasts 100 years in the natural environment. Under special storage conditions, 500 years!
A document is written through optical processing on this special film by shrinking it to a level which cannot be read by the naked eye . And in order to read it, microscope-like devices capable of high magnification are required.
And we are interested in the lenses of these devices!
Little gems in flea market
In the first article linked above I introduced the Otamat101 20mm f2.8 microfilm lens, which sold out very quickly after it was revealed what it was capable of. I was one of the lucky buyers, I was able to order it for £20. The photo below shows an eBay listing from the same seller a few weeks after I bought it:
An listing that was almost 40 times the original price! I don’t know if he was able to sell at that price, but the listing was canceled after a while. An exaggerated example. But there have been cases. The JML 21 microfilm lens is currently impossible to find. It reaches equivalent to 50 times its original price. This is what happens when performance and collector’s curiosity come together.
Unknown Canon lens
The subject of this article is another microfilm lens. My friend Mehmet Baykul bought it for $5. Thanks to him, he sent it to me for review. There is no writing or marking on the lens. The seller declared it as a Canon microfilm lens. I’m assuming it’s Canon, but I’m not really sure.
Canon microfilm lens
In order to mount the lens to the camera, Mehmet attached a 49mm filter adapter to the lens with black tape. Such lenses are in the form of a simple tube. We have to somehow solve the connection problems ourselves. The words 49 etc. you see in the photo are written on this adapter. There is no writing on the lens. Aperture or focal length is unknown.
When I say aperture, don’t think of diaphragm blades that open and close. These lenses don’t have that. They always work wide open. Whatever this wide open value is, the lens is always at that aperture.
I’m using the lens with an Olympus 65-116 variable length tube so I can adjust the framing / magnification. And I immediately take the first shot. My subject model is a beetle of the species “melolontha”. I take a random shot from a place that can give some detail.
With a 65mm tube, the magnification is not much. I don’t want too much anyway. What I’m looking for is sharpness. Let’s examine it a little more thoroughly. Let’s look at the detail photos, cropped from two different areas:
The detail in the center is impressive. There is no problem with the colors. The hairs are very clear. It’s very successful. But there is one thing that caught my attention. Something that might be a problem:
There is no sharpness problem in the photo above. The section was taken from a particularly out of focus area. You know about CA color distortion. Red, green, purple or blue color casts at high contrast edges. So it’s an unwanted rainbow. CA is most annoying in the bokeh. Here we see a lot of bokeh CA. The antenna is haloed in blue below and red above.
It’s not too bad, although we’re a little worried. We have two chances. We have the Photoshop. The CA correction option in Camera RAW sometimes works miracles. And secondly: We are not shooting single frames, we are doing focus stacking. Bokeh CA tends to disappear with focus stacking. When a sharp image in focus from another photo enters the area with bokeh CA during the focus stacking process, the sharp photo will fill that area. Naturally the bokeh will disappear. And CA with it, of course… We hope…
Test shots
It’s time for a real shot. At times like this, I prefer to pretend that I don’t have another lens and do my best with it, rather than taking photos that measure technical values. This time the next photo is of a “drone fly hoverfly”.
After an exciting shoot, we have our image. The Canon microfilm lens works well at medium magnifications. There is very good sharpness in the center. At the far edges, the sharpness deteriorates, but it’s not a big deal. As long as we keep our subject in the center, there’s no problem.
Since I used the lens with the Olympus 65-116 tube, I noted the magnification and working distances corresponding to the 65mm and 116mm tube lengths. If we want to use it with another tube or bellows, we need to make simple proportions according to these values.
For 65mm tube -> Magnification: 1.4X -> Working distance: 6.5cm
For 116mm tube -> Magnification: 2.4X -> Working distance: 5cm
Looking at these values, I guess that the lens has a focal length of around 50mm, but I still have no idea about the aperture.
Canon microfilm lens in front of Tamron 90mm
Last but not least, I wanted to try out a bit of a novel idea. It’s always a lot of fun to experiment with lenses. I wanted to see what we could do by attaching a Canon microfilm lens in front of a Tamron 90mm macro lens. When I connected the filter mounts with the “Macro coupling” adapter, the following figure appeared:
The microfilm lens is very small compared to the Tamron. The diameters of the lenses are very different. I expect problems, but I still want to try it.
The photo above is a letter of the inscription on a 5TL banknote. The magnification is high but the corners are darkened on the full-frame body. Even if we use APS-C, the image will not fill the sensor. This kind of use is not possible.
Conclusion
For those who trust their luck, for the adventurous, for those who want to risk a small amount of money and have some fun, give microfilm lenses a chance! Mehmet Baykul thus got this useful lens. He sent it to me for testing and made this article possible. Thanks again.
Hope to meet you very soon with another microfilm lens (Order already placed!)
