Here, ePHOTOzine's founder Peter Bargh tells us about creating multi-coloured ice patterns using polarisation.
It's a great technique to have a go at if the weather's terrible and you don't want to go out, as it can be done without leaving the house.
All you need is a CD case, some tape and a little bit of pre-planning, along with the essential hardware comprising of an Olympus camera with any lens (ideally with a close up mode), LCD computer monitor and a polarising filter. Oh, and a steady support for the camera.
It doesn't matter if your camera doesn't have a filter thread (often the case when using compact cameras) as you can hold the filter over the lens when taking the shot.
First the preparation. Prise out the CD retaining tray (the bit with the clips that go through the centre of the cd to hold it in the jewel case) out of a standard CD jewel case. Use the Album type not the slimline or clam case. Close the case and tape around all the edges where there are gaps to make the sides and base water tight. Make sure the top gap is open so you can pour water in. Fill it with water through the gap on top and insert it into your fridge's ice box.
When it's frozen set up your mini studio set. Turn on the computer monitor and set it so the background is uncluttered. A standard mid grey desktop is perfect, avoid a fancy pattern. If you don't have one and cannot work out how to change your windows desktop pattern open up a mid grey image in an image editing program and expand it to fill the screen.
As the ice will melt quickly in the tray it's best to set up using a different CD case so you can arrange everything and switch to the icy one when you're ready to take a photo. So position your stand-in CD case about 20-30cm in front of the screen. I used a McClamp, but you could use any form of support or even just pile up some books and balance it on top. Remember that the ice will melt as you take photos so you'll need some sheet to protect books and a cloth to mop up excess water. If you're quick you won't end up with much mess.
Position the camera in front of the CD case with the lens set to fill the frame with a portion of the case. If your camera doesn't focus close enough to fill the frame shoot as close as you can and crop the picture when taken. Again you can use books as a support and stack them to the necessary height. Alternatively use a tripod which gives a sturdier and much more versatile support.
When everything is set up switch from stand-in CD to real ice filled CD. Take the front of the case so you have the ice layer and then the back of the case. Balance on your support and make sure the camera back is parallel to the case so you maximise sharpness.
Now adjust camera position to frame in on a specific area of the ice. Areas with cracks or large bubbles can look best. The ice slab will provide lots of different textures and by rotating the polariser you can deliver different colours from the same position.
Focus carefully on the bubbles so they look really clear. You can shoot on automatic as the metering should be pretty accurate.
If you're using a camera without a filter thread hold the polariser to your eye and rotate round until the screen goes black. keep the filter in that position and move it in front of the lens. The shutter speed will probably be slow so set the camera to the self time mode and take pictures using that. The 2 or 10 second delay is enough to allow the camera to be still before the photo is taken.
Take pictures until the ice begins to melt fast. You have about 10 - 20 minutes before a puddle will appear. You can achieve some great colourful abstracts, as shown above.