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View Full Version : Tips - widescreen images




-hh
Dec 2, 2005, 12:07 PM
I've offered up a new thread to be for tips specific to taking widescreen images.


Here's mine:


1. Knowing the details on just how your camera's "Pano Mode" works.

On some Cameras, they have a specific setting that helps you take a panoramic shot. For example, on Canon's P&S, it divides the screen into a 1/3rd & 2/3rds part to help you allign the composition (and probably make it easier for their stiching software to put them together)

I've learned the following things to be aware of. Note that while these are specific to at least the Canon A80, they're things to check to see how your camera specifically works:

a. Image Size: regardless of what file size/resolution setting you normally use, the "panoramic" setting may have its own. Canon's A80's is smaller.

b. "Helper" mode: Canon's shoots "Left-to-Right" only.

c. Exposure: The Canon selects its exposure for the entire panoramic set is based on the exposure settings of the first photo that you started the sequence with. This is done presumably to make it easier for the stitching software.


Implications of b & c:

You need to be aware of how your equipment works so that it doesn't trip you up at a bad time.

For example, a "this happened to me": I had a neat mountain top setting where I wanted to shoot a panorama of the mountain top, along with the valleys on both the left and right. The sun position was forward, above the lefthand valley that would be in the shot.

Since this camera's pano helper prompts me to shoot from left to right, the obvious way to proceed is to frame/compose to the left of my subject, and then work my way to the right, across my item of primary interest (the mountain top), then out the right side.

BUT - the results of doing it this way is that my area of primary interest will be strongly underexplosed!

Here's the URL to the stiched together shot (yes, its Machu Picchu):
http://www.huntzinger.com/photo/2004/peru/machu%20picchu%205%20(799-803).jpg

You'll notice that the sunburst on the left is nicely exposed - - that's because it was the first frame shot, so that's the settings that was used across the rest of the frame. But the center then turns out to be too dark (underexposed).

One Quick Fix: start shooting your pano sequence at whatever your primary item of interest is ... whatever it is that you care most about being in proper exposure. You then twist to the left and shoot frames #2, 3, 4 ... back through where you already shot one ... 7, 8, 9, etc. Then, when you go to post-processing (stiching), simply don't use Frame#1! Use just frames 2-9 instead.

Alternative Solution#1: on some cameras, pushing the shutter down halfway will give you focus and exposure lock. For these, you can do this at your center location, then *while continuing to hold the button*, you can twist to the left, compose and start your photo sequence.

Alternative Solution#2: if your stitching software does automatic exposure correction and multiple image exposure harmonizing, then each frame can be individually exposed properly with its own settings. However, this may mean that you can't use the pano helper setting on your camera to help you with alligning the shot sequence.


-hh