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Thread: Stitching Question

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    Stitching Question

    Dear gents,

    I had originally posted a question about a 4x10 workflow for shooting people. On the principle of just doing it, I've decided to shoot with my Dorff and my stash of Readyloads.

    Here's what I imagine:
    shoot three 4x5 frames from left/center/right of my tripod pivot point,
    and stitch them in Photoshop.

    I want to place two people in three/quarters foreground size at each edge as a dominant "bookmark" for where every frame meets the next.
    Posed close together, but one person leaning left, and the other leaning right.
    I suppose in a Landscape photo environment, a large tree can substitute for people, for the sake of argument......

    1. How do I frame this so that the software can make an even cut, and a seamless joint between the two people?
    Instinct tells me don't frame as if cutting precisely, but include both people in the right edge of Frame 1, and the left edge of Frame 2.
    Or is this making matters worse for the software to find the seam?

    2. I am told there's software as well that can take a stack of frames, of the same scene but shot at varying planes of focus - and somehow meld all of them to achieve a natural look?

    I have never had reason to do stitching, til now, so I'm just catching up on the reading.Again, I am not aiming for achieving a perfect seam for pure landscape. It's more like a panoramic group portrait of clusters of people against a natural background.

    To be printed as 3x4ft prints to be joined when hung, though 3x12ft continuous print might work too, if the stitch seems seamless.

    thanks again for the usual generous advice.

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    Re: Stitching Question

    First, why don't you try something like Photomerge in Photoshop to see how the process works. With photomerge, it does not simply blend a straight edge, but finds the best line to make the seam. You can go in it afterwards and manipulate the masks if need be. But the seam will not be regular and not where you may expect--but usually excellent.

    You also should have an overlap of about 50% on the frames. That will help the software create the best solution.

    BTW, your pivot point should be at the front standard and then shift the back with the lens fixed. If you are rotating the camera, still use the front standard as the pivot point, but then you are going to be dealing with a projection in processing. Because the projection will puch and pull the image data to fit the projected space, you will need to be loose in your framing as you will have to crop the final stitch to make straight parallel sides. I usually use a cylindrical projection as it is easier to predict and works best with the subjects I shoot. The "perspective" projection might seem ideal, but you may find that will distort your figures similar to the stretching you experience with the wide-angle effect caused by very wide lenses.

    I would shoot some test to figure out the process and see how it will come together.

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    Re: Stitching Question

    BTW, I have printed 44" x 120"" panos that used photomerge.

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    Re: Stitching Question

    thanks Shashin for the info.
    No possibility of a test before my shoot - but will shoot loose, and allow for large overlap,
    as you suggested.
    btw, I wasn't sure what you meant by keeping the front standard as my pivot point??I was assuming that I would find a center frame, and then swing the whole camera on the tripod fixed in place, from left to center to right...
    thanks again.

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    Re: Stitching Question

    Ocarlo, so when you swing a camera, if the lens moves, you will have parallax--basically, the point from where the lens is taking the picture is different and so foreground object don't keep the same position as background object. It is kind of like view out of one eye at a time--the foreground object shifts in relation to the background as you change eye.

    If you can swing the camera around the lens, rather than the middle or back, you keep the entrance pupil of the lens stationary. You can actually see this on the ground glass. Look at two points, one in the foreground and one in the background, and as you swing the camera, does the left/right positions change in relation to each other--do they get closer or further apart as the camera is rotated. If the camera is in the correct position, there should be no change.

    How important this is, depends on how close the foreground objects are--I have certainly made lots of handheld panos and they came out fine for the most part. The few artifacts were easy to clean up.

    Do a Google search for stitching panoramas and nodal slides. That should explain it. If you have a digital camera, I would suggest making some panoramas around the house and neighborhood just so your can get a handle on the results and process. In some ways it is simple and straightforward, in others it can be tricky. A few practice panos would help you visualize your results. I would also try the same pano with different stitching projections like perspective, cylindrical, and reposition just to see how they affect the image.

    I have used both swing-lens and fixed lens film panoramic cameras before and so I had some experience when starting to stitch, but stitching still is not quite the same. Since this is your first shot and it seems like it would be hard to reshoot, a little practice, even with a cell phone or P&S, will be valuable. My first stitched panos were not that great, both with technique, but also framing and composition. The panoramic space is very different and the projection can really impact that.

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