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Taking a Micro Photography　
Minoru Akiyama

(Shooting Microscopic Images)---(1)

Even if you take a microscope, there are many lens, lights settings, peripheral equipments and many other items, which are met with their purposes. Since most of my works are done using a polarized light microscope, I will explain examples centered on it.

To put out reflections, we sometimes install a polarized light filter on the camera.
When I prepare the two pieces of the filter and turn one, it turns black. This is because polarized elements are crossed in a right angle and light will not be able to go through. (I call it "Cross Nicole".)

Using "Cross Nicole" polarized filters and putting a folded cellophane such as a cellophane used for cigarette packaging between the light, transparent cellophane changes into bright colors such as blue, yellow, and green. This is because if you put such objects which does double refraction between "Nicole's Cross", interference colors will appear.
(It is the same effect as an oil membrane or soap bubbles.)

Polarized light microscope is applies this principle. To put it simply, it means that putting the polarized light filter to both the top and bottom of a specimen of a general creature microscope would become a polarized light microscope.

If you look at a specimen such as a crystal which does double refraction by polarized light microscope, you can see bright interference colors. Originally, it is used combined with a compensator, to analyze structure of things such as rocks, medicine, food, fiber, and organization of creatures.

To take a microscopic photograph, a camera lens is not used in principle. Instead, an object lens, and a photographic lens are used. The important one is the object lens. The lens needs to be a Plan type object lens that is able to focus from the center to the very edge. Other lenses only focus on the center, while the graphics farther from the center will be blurred.

Object lens has a number called N.A. which shows the definition power. When you blow the microscopic photograph and look at it from 25cm away, the last magnification will be 1000 times that of the N.A. value. In theory, if you take a picture using an object lens with an N.A. value of 0.25, you can only blow it to 250 times. If you blow it over that, you would call it "stupid blowing".
However, if you expand the photograph 250 times using a 35mm film and a 4×5", seen from the film granularity, it is evident that the latter is superior. For the above reasons, I use only a large-sized camera.

Making a specimen

They are many crystal substances around us, in which interference colors appear, such as sugar, sodium bicarbonate, chemical seasoning, and salt.
In addition, if you enter a darkroom, interference colors will appear from things such as methane, sodium thiosulfate and red prussiate of potash.
Furthermore, if you look for it, vitamin C, naphthalene, aspirin, and other substances are also crystal substances.

You can make a specimen of crystal by dissolving a very small amount of crystal on the slide glass and making it become re-crystallized (To put it precisely, it is just called "vaporizing the solvent".).Even if I just say crystal, from the viewpoint of what dissolves them, there are various kinds of crystals. Some are dissolved by water. Other by heat, by alcohol, by oil, or by a special dissolvent. If you want to dissolve some crystals, it is better to check the nature of crystals beforehand. For example by "Physics and Chemistry Dictionary" or "Japanese Pharmacopoeias" or some other documentation.

Generally talking about a micrograph, it means the picture of a subject's accurate form because it is normally taken for research purposes, which means that most picture are showing what you would normally call "crystals". But I try to take a picture of re-crystallization which is very different from what would normally be called a crystal. Because that would make a much more interesting specimen as a photographic subject.

Making a specimen
They are many crystal substances around us, in which interference colors appear, such as sugar, sodium bicarbonate, chemical seasoning, and salt. In addition, if you enter a darkroom, interference colors will appear from things such as methane, sodium thiosulfate and red prussiate of potash. Furthermore, if you look for it, vitamin C, naphthalene, aspirin, and other substances are also crystal substances. You can make a specimen of crystal by dissolving a very small amount of crystal on the slide glass and making it become re-crystallized (To put it precisely, it is just called "vaporizing the solvent".).Even if I just say crystal, from the viewpoint of what dissolves them, there are various kinds of crystals. Some are dissolved by water. Other by heat, by alcohol, by oil, or by a special dissolvent. If you want to dissolve some crystals, it is better to check the nature of crystals beforehand. For example by "Physics and Chemistry Dictionary" or "Japanese Pharmacopoeias" or some other documentation. Generally talking about a micrograph, it means the picture of a subject's accurate form because it is normally taken for research purposes, which means that most picture are showing what you would normally call "crystals". But I try to take a picture of re-crystallization which is very different from what would normally be called a crystal. Because that would make a much more interesting specimen as a photographic subject.

On a micrograph, making a specimen is the most important and stressful job.

It is a continuation of trial and error to decide things such as choosing the method of re-crystallization, amount of a sample.
Because the process of re-crystallization is affected by conditions such as temerature and humidity, it is almost impossible to recreate the same re-crystallization. Therefore, I try to make the re-crystallization as thin as possible by using samples of the smallest amount, and taking the picture in the least time possible.

I receive questions asking me if I put the cover glass on when I make a specimen. Most object lens equal to or more than 10 times is designed to calculate a refractive index of cover glass (thickness 0.17mm). And my experience says that there is no influence in sharpness due to the cover glass using an object lens of 10 times expansion. Rather than that, we should focus on the difference of re-crystallization influenced by the cover glass.

Until now, I have gotten more than 400 kinds of crystals using various routs, but half of them did not become a picture. But I resume the hard work as an enjoyment for the deepness of re-crystallization.

Taking a microphotograph

As for the illumination of a microscope, usually a tungsten lamp or a Halogen lamp is used. Electric bulb itself is dark with 5-50W, but it is much brighter than expected due to the condenser lens which collects the light.

In addition, I often regulate brightness by changing the voltage (different by the model of machines) or by using a color temperature filter.

In case of color photography, I choose a tungsten type film. (There seems rather impossible to change the color by using a day light type.)

As for the exposure, 35mm cameras with TTL exposure meters are easy to handle, or a exposure meter with a booster (Minolta) is also easy to use. There is also the option of making an exposure table of your own by finding out the relation of the photographic output to that of the exposure meter placed on top of the ground glass.

On a microphotograph, you need to pay most attention to the problem of blurring. If you are not confident, you can open the shutter of the camera and use the on/off of the flash bulb as a shutter

The microscope photography itself is not very difficult. The important thing is the patience in making a specimen, and the sensitivity of cutting out the picture to complete it, which differs from person to person.

Taking a microphotograph
As for the illumination of a microscope, usually a tungsten lamp or a Halogen lamp is used. Electric bulb itself is dark with 5-50W, but it is much brighter than expected due to the condenser lens which collects the light. In addition, I often regulate brightness by changing the voltage (different by the model of machines) or by using a color temperature filter. In case of color photography, I choose a tungsten type film. (There seems rather impossible to change the color by using a day light type.) As for the exposure, 35mm cameras with TTL exposure meters are easy to handle, or a exposure meter with a booster (Minolta) is also easy to use. There is also the option of making an exposure table of your own by finding out the relation of the photographic output to that of the exposure meter placed on top of the ground glass. On a microphotograph, you need to pay most attention to the problem of blurring. If you are not confident, you can open the shutter of the camera and use the on/off of the flash bulb as a shutter The microscope photography itself is not very difficult. The important thing is the patience in making a specimen, and the sensitivity of cutting out the picture to complete it, which differs from person to person.

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	Taking a Micro Photography	Minoru Akiyama
	(Shooting Microscopic Images)---(1)