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Shells fusion X-ray photo
Long time I dreamed of this fusion image of shells. Because already on a lightbox some of the shells are transparent and have nice colors. I like the shining through effect very much.
The X-ray image is a compromise of structure and density resolution, depending on the maximum energy the mammography system is able to produce.
Today I’m not at all in a stable state due to a recurrent infection. So I allowed me to do this image instead of hard working.
Shells fusion X-ray photo © Julian Köpke It is the light inversion in Lab color mode that shows more of a X-ray look and feel. The colors are pretty close to the bright image.
Shells fusion X-ray photo with inversion of the L-channel © Julian Köpke -
Primroses
I felt very much attracted by these primroses. They were close to purple and red and I could see them already as a beautiful print.
But how photographing them on a lightbox ? They always toppled over. Many efforts were useless. Blossoms tend to move, always.
On this photograph I put the blossoms top-down. Because any arrangement could be done then. It works !
Purple Primroses © Julian Köpke A different color show the orange primroses. Composition with or without leaves ? Without gives more the impression of a painting.
Primroses II © Julian Köpke 
Primroses I © Julian Köpke -
Three vetches
X-ray images give an insight into the inner (or hidden) structure of a flower. HDR images on a light box are quite close to this.
Today I wanted to show the softness of petals and went to my dealer. She sold me three vetches, not really expensive for the purpose.
This is my third composition today of the three vetches on my lightbox. The play of the light in the petals resembles to some extent X-ray images.
Three vetches © Julian Köpke -
End of wintertime
Our weather is more and more weird. Today was the second day with a warm sun and a blue sky. Nights are getting pretty cold, days up to 25 degrees Celsius.
Cleaning up our garden led us to some old physalis which were a little more than a skeleton. In autumn these fruits look like lanterns, now they resemble an X-ray.
I did this shot on a lightbox using manual HDR technique.In Lab color mode I obtained this image with a pur black background.
It’s an exoskeleton for the fruit inside which remains that way without bruises.
Physalis after winter has gone. © Julian Köpke -
FAQ: High Dynamic Range
X-rays were initially used for research in atomic physics and medical diagnostics and therapy. Their ability to reveal structures inside an object even with an opaque surface was the driving feature of scientific and technical development of X-rays. Nowadays, beside its proven medical usefulness, X-rays are used to examine technical structures and there are telescopes to map X-rays from our Galaxy and the universe. Every radiological technician who starts in its profession learns to do X-rays of common structures like flowers, animals or teddy bears.
In the digital era, X-ray images are obtained using sensors, while film was used historically. The sensors in the medical radiological field have dimensions such as 24cm x 30cm or 43cm x 43cm. The corresponding spatial resolution for these sensors is between 70µm and 140µm. A typical high-end camera used by a professional or advanced amateur photographer might have a pixel resolution between 4 and 8 µm. Therefore, photographers might well wonder if there is any precise imaging possible with such pixel size. Let’s look at this a little more closely.
X-rays, like visible light, can be characterized by their energy or wavelength. Shorter wavelengths correspond to higher energy. The capability to penetrate an opaque structure increases with energy. If you think of a photon as a particle, smaller particles with higher energies penetrate an object more easily. An overview of this relationship is given in the table shown here:
To make this more clear, here is a series of X-Ray images with increasing energy. The first image was obtained with 40 kV which corresponds to a wavelength of 0.031nm. Our eyes are only able to see wavelengths between 400nm (blue) and 750 nm (red). Therefore, photons with a wavelength at 40 kV cannot be seen with the naked eye. The peripheral parts of the Nautilus shell are clearly depicted. A photographer would classify the circle at the center of the shell as „blown out“. In fact, they are not blown out. The radiation is not able to resolve the structure, because the wavelength of the X-rays is too long in this case to penetrate the shell.
40kV 10mAs 0.031nm Let’s go to shorter wavelengths (implying higher energies). Using 50 kV or a wavelength of 0.024nm gives more structure to the central parts. The photographic impression of a „blown out“ center is reduced. However, looking at the peripheral parts of the Nautilus there is a loss of intensity and a more grayish impression. It is conceivable that this might be regarded as an overall acceptable but subtle effect.
50kV 2mAs 0.024nm To take this further, we can go up to 60 kV or down to 0.0207nm. The center is now close to perfectly „exposed“ with some detail apparent, although some smaller structures are still not resolved. The intensity loss at the peripheral parts increases and is now pronounced. A photographer would clearly regard the periphery as „underexposed“.
60kV 2mAs 0.0207nm The last example of this direction of higher energy and shorter wavelengths is 70 kV or a wavelength of 0.0177nm. The photons wavelength is now 57% compared to 40 kV. You may think of this as „smaller“ photons. The result is a clearly depicted core with a complete loss of peripheral structure. A photographer would have every reason to be worried about „underexposure“ and loss of detail everywhere but the center.
70kV 10mAs 0.0177nm What we’ve seen here is that the capability of X-rays to penetrate an object and to go through an object is dependent on energy levels. With shorter wavelengths X-rays go through an object without disturbance but our sensor is „blown out“ at the peripheral parts of the Nautilus shell. Using 70 kV the central parts are much better resolved, but the periphery is too dark. The energy to use for any X-ray image therefore often depends on the primary goal of which portion of the subject is most important to capture.
In a certain sense, the compositing of images with different energies into one image can be compared to the HDR process of photography in the field of visible light. Whereby in visible light the intensity plays the essential role and not the light energy, which determines the color. When X-raying an object that requires different energy levels for accurate representation, I would therefore also speak of a High Dynamic Range image.
If combined, the four exposures shown provide a beautiful, nearly weightless image:
Nautilus X-Ray Energy Compressed © Julian Köpke -
X-ray fusion images
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FAQ: Fusion imaging
Explanation of the idea
Fusion imaging is a child of the digital era of mapping structures. Before image fusion was used in diagnostic radiology, astronomers used it to extract new insights from our universe. Fusion imaging of flowers can be beautiful. And, maybe, it’s a starting point for research in new fields.
The use of photography was initially, after its invention in the 40s of the 19th century, nothing more than a gadget. Only by astronomers, that used used photography for detection of asteroids, photography became a serious matter. By comparison („blinking“) of photographies astronomers discovered mobile objects within a field of fixed stars. In Heidelberg, Max Wolf (1863 – 1932) has been a pioneer of astrophotography.
Imaging of flowers is nothing new. But in the digital era of photography, the mapping possibilities changed fundamentally. It became possible to create the illusion of transparency or translucency by using a set of HDR images at the HighKey side of the exposures. The procedure was introduced by Harold Davis.
X-rays were initially used for medical diagnostics and therapy. Their ability to reveal structures inside an object with an opaque surface was the driving feature of technical development in this field. Nowadays x-rays are used to examin technical structures and there are telescopes to map x-rays from our Galaxy. Every technician who started in its profession learned to do x-rays of interesting structures like flowers, animals or teddy bears. X-ray images of flowers are nothing new.
Transparent looking flowers and transparent looking x-rays of the same flowers are each already for itself appealing to our eye and mind. By combining two digital images of the same structure in visible light and x-ray there is something new to happen. We name this combined procedure „fusion imaging“ and the result of a combination a „fusion image“.
How it works in a nutshell
First, create an HDR of flowers (see Harold Davis). Then create an x-ray of the same composition (see FAQ: X-Ray of Flowers). Last, not least: combine the HDR image and the corresponding x-ray with appropriate editing software.
HDR Calla lilies © Julian Köpke 
X-ray Calla lilies © Julian Köpke 
X-ray fusion image of yellow Calla Lilies © Julian Köpke
