February 13, 2015 3 Comments
I suppose it is bad luck when the morning brings temperatures much lower than they should be for this time of the year. This morning I heard the news reader mention that the dreaded ‘Polar Vortex’ has returned. I took my iphone out on the deck this morning along with bird seed for some extremely fluffy chickadees, redpolls and pine grosbeaks. I stopped for a photo of our deck thermometer. It is the coldest morning of the year so far and January has come and gone.
But for me the photographic silver lining in this Friday the 13th cloud is the potential for some good window frost photos from the back window of the garage. We have an unheated garage and the back window looks out on an expanse of snow covering the lawn. My woodshed casts a blue shadow for the first hour or so of morning after sunrise. In addition there is a band of dark spruce trees behind the lawn so I have a choice of backgrounds ranging from pale blue to dark. Sure enough the frost feathers had formed. I remember Dennis Fast lamenting that he has lost the opportunity to photograph the buildup of window-frost that occurs on cold mornings now that he has a newly renovated sunroom with more modern air-tight windows.
Achieving sharp macro photos is one of the biggest technical challenges for this project. I have to improvise a support for the camera and lens in the optimum position for these photos. I need to support the camera during exposures on a rather unstable wooden workbench. I found that a beanbag on a milk crate, shimmed if necessary to prevent wobble, works better than trying to set the legs of my tripod on the workbench. The micro lens has very limited depth of field, even at f22, so to achieve sharpness everywhere in the frame I need to position the camera and lens so that its sensor is absolutely parallel to the window frost. I use extra boards under the milk crate to add or subtract height depending on where I need to frame the frost, choosing the nicest swirls against a blue or dark background. The backgrounds are so distant that at f22 they remains soft.
For my frost photography I use a 200mm micro Nikkor with or without a close-up diopter (for extra magnification) that can be attached in front of the lens. The D800 produces such large files that any one can be judiciously cropped if necessary and still produce a Tif of adequate size. I always shoot RAW with a manual exposure of about 0 to +1 depending on the background. I prefer manual White Balance that I can adjust afterwards too. I use my hand to dampen the camera into the bean bag. I use Mirror lockup and a cable release to further ensure sharp results. After each exposure I check the histogram and zoom to 100% on review to assess sharpness (there is a menu setting that activates a button for this action).
Working inside the garage keeps me out of the wind but it is still very cold so I need to dress warmly and use gloves to handle the camera. I like the Freehands photography gloves with flip-back fingertips (held back with neat magnetic buttons). Once I finish I wrap the camera in a big plastic bag and let it warm up inside the house. In a few hours the beautiful frost feathers will sublimate off the window.