Robert Williams Photography offers landscape and nature photography, with a focus on Canadian landscapes.
Fine art prints and stock nature and urban photographs are available at affordable prices.
August 28, 2010: I have added photographs from the Avalon Peninsula (and St. John's) to my article on Newfoundland.
August 24, 2010: A new front-page photograph from Newfoundland.
One notable feature missing from my digital camera and many other digital cameras, is the ability to make in-camera multiple exposures. Some manufacturers are starting to address this feature, but unless you're willing to spend thousands of dollars for a new camera (like the Nikon D2X), you will have to resort to other methods for making multiple exposures.
The Forest Overhead, October 2004
Thankfully, digital photography makes it easy (and cheap) to take a series of single exposures. Photo editing software gives you the ability to combine a set of images together -- it just takes some time and effort to do the work. The only questions are: how do you expose the images, and how exactly do you go about combining them?
With film, exposure of multiple images can be done either by combining images in-camera, or by creating a "sandwich" of two or more slides. Exposure for the two options is a critical issue. For in-camera multiple exposures, you have to under-expose each image, in proportion to the number of exposures you want to combine. For two images, you underexpose by one stop. For four images, underexpose by two stops; eight images, underexpose by three stops. When creating a sandwich, you have to overexpose with approximately the same ratios.
For digital photographs, I've seen other people recommend under-exposing each image just like you do for in-camera multiple exposures. You would then combine the images using layers.
I've been using a slightly different technique, one that is more flexible, and easier.
First, I take each image in JPEG Fine mode, instead of Raw. The added flexibility of processing Raw isn't required for multiple exposures, and JPEG Fine results in a much smaller file, taking less space on your flash card, and on the computer.
I expose each image normally, without any adjustments for multiple exposures. This is not only simpler to figure out, but you don't have to decide in advance how many images you want to take.
When I get the images onto the computer, I read all of the images into my photo editing software at the same time, and combine them into one image using layers. I set the blending mode of each layer to "normal". The only trick you need is to set the opacity of each layer as follows:
The formula is simple: 100/layerNumber, counting the background layer as layer number 1.
The best thing about this method is the flexibility you have when actually creating the final image. You can choose which images you want to include, and how many images to include, long after the initial exposures in the field. Although it takes more time to create the final image, the added control you get is great.
Hollyhocks, August 2004
You can decide how many images to include or you can give one image more emphasis than the rest (as was done in the Hollyhock image above). The decisions are no longer made in the field, but later on, with more control.
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