THE ORIGINAL WEEK 31 CHALLENGE IS STILL AVAILABLE AT THE BOTTOM OF THIS POST
The members have spoken, they want GOOD OLD FASHION TECHNICAL CHALLENGES! Well here it is, never before seen on the PhotoChallenge : CROSS POLARIZATION MACRO Photography.
I’m talking about lighting up your subject with polarized light and filtering that light with an other polarized filter on the lens. It’s an old technique used to reproduce paintings and various artwork as you can eliminate 100% of all light reflections.
I first attempted to bring this concept down to macro photography last year. I used my in-house wildlife model, PESTO. With Pesto’s help I was able to fine tune my setup and produce some great images in the field. You can read my article on cross polarization here on my blog : http://www.trolettiphoto.com/blog/2014/9/Pesto-the-Barred-parakeet-and-Cross-Polarization
It looked good on Pesto’s feathers. Barely a reflection in his eye. It was but the beginning. Over the winter I tuned my flashes with 3rd party diffusers and attached the Rosco polarizing Gels to them with the use of velcro dots. I now have cleaner softer light that is easier to control in the field. The above image of a Black Swallowtail Butterfly Caterpillar is testimony to my new setup.
The exact same setup was used on this caterpillar looking Sawfly Larvae. In this case the black background is not only due to a lack of illumination, it’s a silver reflector bouncing the light directly back at the lens. The cross polarized light reflects back as black light, if your setup is well tuned. I also cover my subject with a second reflector as to eliminate reflections from sunlight.
I’m using a fairly humble setup. A Nikon D810 mounted to a Nikkor Micro 105mm lens. I sometimes use a 1.4x teleconverter or/and extension tubes depending on the size of the subject and the working distance I need. I mount all these components to a Manfrotto telephoto support mounted in turn to a macro rail. This allows me to move the camera front or back without moving the tripod. My lighting source is the Nikon R1 close-up Speedlight flash system. There you can see the Vello diffusers and the Rosco Polarizing filter gels. I use a Hoya Pro Digital Circular polarizing filter mounted in front of the lens.
WHAT YOU WILL NEED:
1. Some type of Macro Lens
2. A Circular Polarized Filter for your Lens
3. 1 or more external flash, preferable. (You can also use a built in flash)
4. A linear or polarized filter for your flash I.E. Rosco Polarized Filter Gels (A lens filter or even a good pair of polarized sunglasses will work.)
5. A reflector / diffuser to block light from external sources such as sunlight.
6. A Tripod will make life much easier
The trick is to turn the polarized filter on your lens until the polarized filter in front of your flash turns completely black. I do this in front of a mirror. You can also use a small flashlight behind the flash polarizing filter to make sure you get it just right. It’s important to mark and remember the orientation of your flash polarizing filter and the lens polarizing filter. They have to remain aligned this way or you will not get the desired results.
PRODUCE A MACRO IMAGE OUTDOORS USING THE PRINCIPLES OF CROSS POLARIZATION. Your subject does not need to be a bug it can be anything outdoor in nature. (NO MAN MADE OBJECTS) Flowers show spectacular colors when using CROSS POLARIZATION. (Ornamental flowers accepted as long as they are outdoor)