• X-Ray

    Nautilus and Flowers

    How to prepare a X-ray session ? What flowers suit to a Nautilus shell ? Where does color come in ? 

    I went to my gorgeous florist to have a look what offer she can make during wintertime. My phantasy were spinning around something ethereal or unrealistic. I bought some flowers with respect to their shape. 

    The Anthuria caught my eye immediately. The Tulip was still closed and got more and more yellow within hours.

    All these compositions shown here were made with dual energy X-ray. The lowest energy of the tube is 40kV, which yields with 4 mAs a quite good insight of flowers. For the center of the Nautilus shell, 70kV and 2.5 mAs is more appropriate.

    My first composition was a Nautilus taking off a bouquet of flowers. This reminded me of Renaissance engravings full of symbols. I do not feel depressed. The representation as a X-ray positive jsut shows the bouquet.

    Miraculous flowers and nautilus shell © Julian Köpke
    Miraculous flowers © Julian Köpke

    A more grounded composition is the second with a Nautilus shell moving towards the roots of my bouquet. Hopefully, the plants will survive. The positive representation always needs some extra editing. By just inverting the Blacks and the Whites the Nautilus would be too dark. Our reception cannot be just inverted and feels alright.

    Flowers and Nautilus © Julian Köpke
    Flowers and Nautilus © Julian Köpke

    With the look-and-feel of old engravings in mind the third composition ist between surreal and a still. It took me some time to mask out the flaws of an original X-ray to get a true black background. Masking can be done iteratively and easily combined with Photoshop. („That’s what Photoshop is made for  !“).

    Some colorizing was done to overcome missing photographic shots. There was simply no time in my X-ray unit to do both at a time.

    Nautilus shell as a vase or a vessel („Hansekogge“ or cog) © Julian Köpke
    Positive representation of Nautilus shell as a vase or a vessel („Hansekogge“ or cog) © Julian Köpke
    Coloured Nautilus shell as a vase or a vessel („Hansekogge“ or cog) © Julian Köpke
    Coloured positive representation of a Nautilus shell as a vase or a vessel („Hansekogge“ or cog) © Julian Köpke

    My fourth composition is called „The Argonauts“. The Nautilus shell serves as Argo, the legendary fast ship, with its crew, called Argonauts. The colored version is more convenient for our eyes. As before the X-ray positive looks more ethereal. 

    A Nautilus with flowers as Argonauts © Julian Köpke
    A Nautilus with flowers Argonauts © Julian Köpke
    X-Ray positive of a Nautilus with flowers as Argonauts © Julian Köpke
    Colored X-ray positive of a Nautilus with flowers as Argonauts © Julian Köpke
  • X-Ray

    Transparency and Energy in X-Rays

    You always need some time to find out the best exposure values for a photo. Same idea holds in X-Ray imaging.

    Today I did an x-ray series with my biggest Nautilus shell on a conventional radiography sensor, not a film. Starting from the lowest possible value 40kV an increment of 10 kV up to 70 kV can be seen in the images:

    40kV 10mAs

    Black regions in the image a transparent, white are opaque. The center of the Nautilus has a loss of structure.

    With 50 kV the structure in the center of the Nautilus is better depicted wheras the edge gets more transparent:

    50kV 2mAs

    Same effect for the center and the edge can be seen with 60 kV:

    60kV 2mAs

    With 70 kV it’s an exaggeration for the edge and best depiction for the center:

    70kV 10mAs

    Higher kV means more transparency for denser structures but a loss of structure in transparent areas. 

    At fixed energy, X-Ray imaging behaves like a shadow related to visible light. When photographing, there is not chance to look through an opaque object. With higher energies, x-rays go through opaque objects and can be collected on a sensor. 

    Composing the images obtained at different energies is an X-Ray HDR image:

    Nautilus X-Ray Energy HDR © Julian Köpke

    The representation of an X-Ray with white on black is a reminiscence of the film era. Radiologists just looked at the negatives ! Inverting black and white shows the positive image, like a print. Here I show the same image as positive, but rotated and flipped horizontally. Look how ethereal it appears now:

    Nautilus X-Ray Energy Compressed © Julian Köpke
  • X-Ray

    X-Ray of Christmas cookies

    Thanks to my hard-working father-in-law we enjoy every year phantastic cookies. This year I had to cope with different archiving modalities in mammography due to quality management. This image was an idea to enjoy Christmas in advance with a composition of a Poinsettia. Simple structurizing effects render this image into a sort of cookie smelling painting.

    Poinsettia. Texturized x-ray of cookies. © Julian Köpke