Panoramas - Shift Lens Style
Panoramic images have become a "norm" these days. With the ease of photomerging and the seemingly unlimited shooting potential of digital cameras, panoramics have become a "dime-a-dozen" commodity. However, there are some scenes that just demand to be presented in a panoramic style regardless of our own personal bias for or against it.
The common method of shooting a panoramic image is to take multiple pictures while rotating the camera slightly between each frame. We then merge these images together using the overlapping areas to blend, combine or otherwise slice and dice to get the seams to disappear. This is usually pretty easy, but most lenses have enough distortion to them (especially zooms) that the task can either be difficult or the image is compromised. In the above photograph (click on it to see a larger version), an additional issue is the fact that the shooting position is substantially below that of the subject, which would cause tremendous "leaning" inward of the mountains and the trees. Panoramics RARELY work well when the camera isn't perfectly level.
To get around these issues, I used the Olympus Zuiko 35mm Shift Lens for both perspective control AND for generating the multiple images. A rule-of-thumb regarding perspective control lenses is that when the film (sensor) plane and the object are parallel to each other, there will be no visible vertical convergence. With a shifting lens, we are able to slide the lens upward to raise the framing of the image to include our subject.
To create this panoramic, I shot FIVE images with the lens shifted far-left, mid-left, center, mid-right and far-right. Even though you can JUST get by with three images, I prefer five since it gives me much greater latitude in blending and merging options. As per usual with panoramics, you'll need to use manual-exposure mode to keep things matched up. Even at that, there will be a very slight exposure variance between exposures which are easy to correct.
I used Adobe Photoshop Elements to create the photomerge (however, the raw conversion on the files were performed in RawShooter Essentials) and I kept the merged elements in individual layers. If Photoshop hasn't already done so, make sure the CENTER image is on top, with the far-left and far-right images on the bottom. To match the exact exposure of each layer, click on underlying layer and open the Brightness/Contrast Dialog Box. This box opens with the brightness field active. just press the keyboard's up/down arrow buttons until the "line" between the layers disappear. Close and go to the next underlying layer (farther to the side) to repeat the process. ALWAYS work center out.
Once you have all of the layers matched up it is time to adjust the blend point. To make sure the layers are properly positioned, change the upper layer (ie. center image) to 50% visibility and then move the lower layer till the images line up correctly. Change the visibility back to 100%. Repeat for each underlying layer.
Adjusting the blend point is easier with a pen-tablet, like a Wacom. Regardless, you will use the eraser tool with a wide fuzzy penumbra. Click on the upper layer to edit it. Start erasing the edges of this layer to softly reveal the underlying layer. Objects can be worked around--there is no reason to work in a straight up/down line. Just artistly blend and reveal. Repeat for each overlapping layer, ALWAYS working from center out.
Save often. Now comes the critical point. Once you have all of the layers positioned and blended correctly, you can flatten the image. Save this flattened image as a NEW file. DO NOT overwrite your project--you might want to revisit it. This new file can now be sharpened, color adjusted and cropped to eliminate the rough edges.
The profile portrait of Mt. Rushmore's George Washington is an example of this editing method as well as use of the 35/shift lens on the Olympus E-1. By raising up the lens I was able to keep convergence from occuring and by using the shift lens for multiple parallel shots, this panoramic was able to be created.
The common method of shooting a panoramic image is to take multiple pictures while rotating the camera slightly between each frame. We then merge these images together using the overlapping areas to blend, combine or otherwise slice and dice to get the seams to disappear. This is usually pretty easy, but most lenses have enough distortion to them (especially zooms) that the task can either be difficult or the image is compromised. In the above photograph (click on it to see a larger version), an additional issue is the fact that the shooting position is substantially below that of the subject, which would cause tremendous "leaning" inward of the mountains and the trees. Panoramics RARELY work well when the camera isn't perfectly level.
To get around these issues, I used the Olympus Zuiko 35mm Shift Lens for both perspective control AND for generating the multiple images. A rule-of-thumb regarding perspective control lenses is that when the film (sensor) plane and the object are parallel to each other, there will be no visible vertical convergence. With a shifting lens, we are able to slide the lens upward to raise the framing of the image to include our subject.
To create this panoramic, I shot FIVE images with the lens shifted far-left, mid-left, center, mid-right and far-right. Even though you can JUST get by with three images, I prefer five since it gives me much greater latitude in blending and merging options. As per usual with panoramics, you'll need to use manual-exposure mode to keep things matched up. Even at that, there will be a very slight exposure variance between exposures which are easy to correct.
I used Adobe Photoshop Elements to create the photomerge (however, the raw conversion on the files were performed in RawShooter Essentials) and I kept the merged elements in individual layers. If Photoshop hasn't already done so, make sure the CENTER image is on top, with the far-left and far-right images on the bottom. To match the exact exposure of each layer, click on underlying layer and open the Brightness/Contrast Dialog Box. This box opens with the brightness field active. just press the keyboard's up/down arrow buttons until the "line" between the layers disappear. Close and go to the next underlying layer (farther to the side) to repeat the process. ALWAYS work center out.
Once you have all of the layers matched up it is time to adjust the blend point. To make sure the layers are properly positioned, change the upper layer (ie. center image) to 50% visibility and then move the lower layer till the images line up correctly. Change the visibility back to 100%. Repeat for each underlying layer.
Adjusting the blend point is easier with a pen-tablet, like a Wacom. Regardless, you will use the eraser tool with a wide fuzzy penumbra. Click on the upper layer to edit it. Start erasing the edges of this layer to softly reveal the underlying layer. Objects can be worked around--there is no reason to work in a straight up/down line. Just artistly blend and reveal. Repeat for each overlapping layer, ALWAYS working from center out.
Save often. Now comes the critical point. Once you have all of the layers positioned and blended correctly, you can flatten the image. Save this flattened image as a NEW file. DO NOT overwrite your project--you might want to revisit it. This new file can now be sharpened, color adjusted and cropped to eliminate the rough edges.
The profile portrait of Mt. Rushmore's George Washington is an example of this editing method as well as use of the 35/shift lens on the Olympus E-1. By raising up the lens I was able to keep convergence from occuring and by using the shift lens for multiple parallel shots, this panoramic was able to be created.
1 comment:
A tip on making the blending process easier:
when you invert the top layer, and then make it transparent 50% the blending is perfect when you get an (almost) perfectly grey zone between the images.
(And noow you now how they did the 'emboss' filter as well.
Iwert.
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