Introduction: Transparent Discharge Plate for Kirlian Photography
To take Kirlian photographs using a digital camera requires a suitable high voltage power supply, a digital camera and transparent discharge plate. The Kirlian photograph of the U.S. quarter was shot with a digital camera through a transparent discharge plate (TDP).
This Instructable is a companion to my two other Instructables on Kirlian Photography.
Building a Transparent Discharge Plate (TDP) will save you about half the cost of buying one. Interested? Read on.
Step 1: How the Transparent Discharge Plate Works
This Kirlian photography set up may be used with the following types of cameras; digital, 35mm film, iPhone or a low lux video camera. The illustration shows the set up with a digital camera but the other cameras will work as well. The specifications for the cameras are provided in the Instructable on Shooting Kirlian Photographs.
Using a digital camera requires the use of a flat transparent discharge plate (TDP). The TDP itself is constructed using a glass plate with a transparent, but electrically conductive coating on one side of the glass. The transmission of light through the TDP is usually better than 90%. The insulating material shown in the diagram is a thin piece of transparent glass or plastic and is incorporated into the construction of the Transparent Discharge Plate (TDP).
The subject or object being photographed is in direct contact with the TDP. The high-voltage power source is connected to the TDP. If the object being photographed is inanimate, it is connected to an earth ground. The digital camera is manually focused onto the object through the TDP. The room lights are turned off, or the kirlian photography set-up is covered in a light tight enclosure. Next, the high voltage power source is turned on, once on, the feeble light from the corona discharge should be visible around the object. Next the digital camera shutter is tripped to make a timed exposure of 10-15 seconds. When the camera's shutter closes the high voltage power source is turned off. The digital camera should have recorded the corona discharge around the object which is a Kirlian photograph
Step 2: Construction of the Transparent Discharge Plate
A transparent discharge plate is constructed from four main components; a 4 inch by 5 inch piece of glass that has a transparent, electrically conductive coating of tin oxide on one side, a ring electrode made from thin adhesive copper foil, and two .005 thick pieces of transparent plastic. The transparency of our transparent discharge plates surpasses 90 percent.
The conductive tin oxide coating on the glass can be damaged by a high voltage discharge. To prevent damage a solid electrical connection must be made between the tin oxide coating on the glass and the high voltage power source. The solution for this is simple, we make a ring electrode using conductive copper tape along the perimeter of the glass on the tin oxide side. The adhesive copper tape creates a ring electrode with a large surface area of electrical contact with the tin oxide coating. This large surface area prevents a discharge (spark) forming between the electrical connection to the tin oxide coating and the tin oxide coating itself, when in use.
The transparent discharge plate construction is shown in figure 2. The rectangle ring electrode is made from thin adhesive copper foil, that is 1/4 inch wide and 2 mils thick. You will need two .005 thick pieces of transparent plastic sheet material. The thin transparent plastic sheets are cut 1-1/2" larger than the glass plate on each side, making it approximately 5-1/2" by 6-1/2", as shown.
Step 3: Tin Oxide Coated Glass
When you receive the 4" by 5" tin oxide coated glass, be careful, see figure 3. The edges of the glass are sharp. Visually it will be impossible to tell which side of the glass has the conductive tin oxide coating.
We begin by determining which side of the glass has the tin oxide coating. To do this you need an ohmmeter. Inexpensive VOM's (volt-ohm-meters) are available from local electrical stores or from Amazon.Com. An inexpensive VOM can be purchased for $10.00.
Set the VOM to read OHMS on lowest resistance setting. Bring both probes in contact with one side of the glass plate, as shown in figure 4. The side with the tin oxide coating will deflect the meter, or if you are using a digital VOM, as shown in the photograph, the resistance reading is provided numerically. The VOM in the photograph is showing a resistance of 165 ohms per inch. The other side of the glass, the side without the tin oxide coating will show an infinitely high resistance.
Step 4: Ring Electrode
The thin adhesive copper foil used to make the ring electrode can easily be cut using scissors.
Before placing foil on glass, clean the tin oxide side of the glass thoroughly, so you have a good surface for the copper foil to adhere to. Re-clean the surface throughout the assembly process to ensure that no prints or lint are left on the glass.
The outside dimension of the ring electrode is the same size as the tin oxide glass, with a tab running off on one end. To accomplish this, cut two 4 inch strips and two 5 inch strips of copper foil, equal to the length and width of the tin oxide glass. Remove the adhesive backing and place foil along the edge of the conductive side of the glass, as shown in Figure 5. Cut a one inch piece of copper foil and adhere it the lower right side of the glass. Fold any excess foil in half to create the tab, see Figure 6.
Step 5: Adding High Voltage Wire
Test assembly with an ohmmeter before proceeding. Touch the tab of the ring electrode with one probe and touch the tin oxide coating with the other. You should show good conductivity (low resistance).
Next, solder approximately 18 inches of high voltage wire to the protruding tab. The wire should lay perpendicular to the copper tab as shown in Figure 7. Try to solder the wire so that it lays as close to the glass as possible. This will connect the transparent discharge plate to the HV source when you are finished.
Step 6: Protective Sheet(s) for the Glass
Since the conductive coating of the transparent electrode is delicate we need to protect it. Purchase two sheets of transparent plastic which is approximately .005 thick. Cut the plastic sheet to a larger size than the tin oxide glass. Add approximately 3/4 inch to all sides of the transparent plastic.
Run a thin bead of clear silicone adhesive around the edge of the transparent electrode, on top of copper foil, as shown in Figure 8. Center the plastic on top of the conductive tin oxide coating (Figure 9). Place a book or flat object onto the transparent electrode to hold the assembly tight and together while the silicone cures. Curing time is approximately 12 - 24 hours.
Step 7: Protective Sheet for the Other Side
Once the silicone is dry, repeat this process on the opposite side of glass by running a bead of silicone around the edge of glass and centering second piece of plastic on top of glass, as demonstrated in Figures 10 and 11. Place a book or flat object onto the transparent electrode to hold the assembly tight and together while the silicone cures. Wait another 12 -24 hours.
You should now have the transparent electrode sandwiched between two sheets of transparent plastic. Next, fill the gap from the edge of the glass to the outside edge of the plastic sheets with silicone adhesive, see figure 12. Place a book or flat object onto the transparent electrode once again to hold the assembly tight and together while the silicone cures. Allow to dry completely before continuing.
Step 8: Create a Frame
Create a frame for your transparent electrode by running black electrical tape along the edges of the transparent electrode to further secure the plastic sheets together (see Figure 14).
First, run the tape along the edges of the transparent electrode. When you reach the edge that has the HV wire protruding from the side, use an Exacto knife to cut a slice in the tape, so that the tape can be secured to electrode without leaving a gap. Figures 14 -18 demonstrate this process.
Then, wrap it around the glass on each side to cover the space between the edge of the electrode and where the copper foil appears, as demonstrated in Figures 19 and 20. The tape serves a dual purpose. First, it helps secure the plastic sheets to the transparent electrode. Secondly, it provides insulation along the edge of the electrode where it is needed. You may want to double tape the corner edges to provide an additional measure of insulation.
Step 9: Ground Plate
Being about to easily ground the object you want to photography safely and quickly is essential. I recommend making a few grounding plate tools to facilitate your Kirlian photography.
This ground plate is made from a small piece of transparent plastic 4” 5” 1/8” thick, a few inches of copper tape (0.25” wide adhesive ) you used if you made the Transparent Discharge Plate, and a few short lengths of plastic I use as legs. The size of the plastic sheet is not important, it should fit under your camera copy stand, see chapter 4. Let’s start with a piece of plastic that is about 4” x 5”. Although any size up to 8” x 10” will work. A piece of black non conductive paper. Tape or glued the black paper, onto the bottom of plastic sheet. The black background provides a nice contrast to the corona discharge that improves the resulting Kirlian images.
It is important that the paper or felt you use be electrically non-conductive. Many black materials like black plastic or black foam board use carbon (graphite) to obtain the black color of the material. Unfortunately carbon is electrically conductive. Having the ground plate made of this will short circuit your object and the corona discharge will not form around the object. This can be very frustrating and time consuming to figure out why you’re not getting any image. I have years of experience shooting Kirlian photographs and it took me an hour or so to trouble shoot the problem back to the ground plate I was using. This particular ground plate was made from black foam board. The black surface was only slightly electrically conductive. But at high voltages involve in Kirlian Photography it was enough to prevent any image from forming. The black side is the working side that will be facing your camera.
Figure 23 shows the two plastic spaces hot glued to the plastic sheet I used for feet. A slit through the center of the sheet for the copper tape to pass through from the top (working side) to bottom (connection side). These legs are important; they create enough space under the ground plate to connect an alligator clip wire to the copper tape without tiling or making the ground plate unstable.
To complete the ground plate secure a piece of black non-conductive paper (black construction paper) or felt to the underside of the plastic sheet. Cut a slit in the paper to pass through the copper tape.
In use the object to be photographed is placed on the copper foil on the top side. An alligator clip wire is connected to the copper foil on the bottom side of the ground plate. The other end of the alligator clip wire is attached to an earth ground. The Transparent Discharge Plate is placed on top of the Object and ground plate as show in figure 25. The camera is positioned above the set-up ready to take a long exposure picture.
Step 10: Parts List
Transparent Discharge Plate:
Tin Oxide Coated (1 side only) Glass 4” x 5”
¼” wide copper adhesive tape. Approximately 24” in length
Clear silicone caulking/glue
(2) 5-1/2” x 7” clear transparent plastic 0.050 thick
Length of HV wire (8-10Kev) approximately 18”
Black electrical tape
Components and Transparent Discharge Kit available from Images SI Inc.
Parts List for Ground Plate: See text
Book on Digital Kirlian Photography from Amazon