Workflow Technique #001
"Stitching in Photoshop"
Dr. William Wolberg
|Why I developed this Action
|In the field, I usually carry only my 70-180 mm f4.5-5.6 micro lens that allows me to take micros of flowers, bugs etc. and moderate tele pictures. Wider-angle shots are not possible. However, to solve this problem, I take two vertical pictures with about a 10% overlap and then use the described technique to stitch the images. Additionally, the resolution is greatly improved by doubling the pixel content. Essentially my 70 mm is converted to a 35 mm lens and the 2:3 35 mm camera format is converted to a 4:5 format.
|What the Action does
|I don't use any of the available panorama editors because they create a blur at the seam. Rather, I use Photoshop and proceed as follows. Make a new, blank file at the same resolution as the two pictures to be stitched, but make it wider e.g. 4000 x5000 pixels at 300 pixels/inch in the case of the Nikon D100. Then, make 50% opaque layers of both pictures and move them to the new background file. Precisely align the two and then use the rectangular marquee tool to draw down along the middle of the overlap. From this point on, the provided Action takes over, saves the selection and makes a new layer from the selected area, loads and inverses the selection, makes another new layer from that selection, and flattens the image. The operator then manually crops the final image to remove excess background.
|Using the Action with other lenses
|With wider angle lenses, some seam editing is necessary particularly with near-far shots. Never the less, even landscapes at taken with a 24mm lens tune out very well. One of the reasons that this method works so well for me is that I use the method mainly with my 70-180mm lens. That lens has its own mount and the optical axis does not change when the camera is panned while in the vertical position. Optical axis considerations come into play in situations where the lens' optical axis shifts when panning.
|Instructions for using the Stitching Action
|Action for download (ZIP)
As I wrote previously, I made a device that permits me to pan around
the optical axis with lenses other than my 70-180mm. I use this with
my 24-85mm lens at 24mm in order to get really wideangle shots.The fall
colors are just coming out in Wisconsin so find myself
|Note: Here are the steps of the action for users of older Photoshop versions
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