It’s getting easier to make panoramics with today’s cameras.
Some will actually do the stitching together for you without the need for
software. But unless you take control of the process, you may be selling
yourself short on results.
Here is a checklist you can follow in preparation for
shooting your panoramic. It may look a little daunting, but it will become old
hat with a little practice:
- Arrive Early In
order to get through this checklist, you’ll need the extra setup time before
the light changes!
- Use a Tripod A panoramic is comprised of a series of
adjacent photographs stitched together in software to form a single
wide-angle image. In the stitching process, the software does its best to
match adjacent images seamlessly, but there is usually a bit of twisting
required to match them perfectly. This requires cropping the final
panoramic. Unless the individual images are shot with the camera
absolutely level, the twisting and subsequent cropping may get to the
point where much of the scene is lost.
- Level the Tripod and Camera I have a bubble level on the base of my
tripod which I use to get the legs levelled up first. I also use a bubble
level that slips onto the camera’s hot shoe, which I use to do fine
levelling adjustments. The reason for using both is that uneven legs may
give me the impression that I have a level camera at one position, using
the hot shoe level. But as I pan, I would likely see the level drift off
centre. Once you have tweaked both the legs and the pan/tilt head, try
panning through the intended range of your panoramic to ensure you have
optimized both.
- Set the Camera to Manual (M) mode Imagine you’re shooting a panoramic
made up of photos that have dramatically different light content. In any
mode but Manual, each photo would be exposed differently because the light
metering system built into your camera tries to set the exposure
automatically to an average 18% grey level. In this scenario, the
panoramic wouldn’t look right because the inherently darker scenes would
be forced to look lighter compared to the others, resulting in a
patchy-looking result. Sure, you could try matching the exposures in
software before stitching, but it’s easier to get it right in the camera.
I pan the entire scene first, using the digital meter to set a shutter
speed/aperture combination that averages a normal exposure. As a result, some
shots will be over-exposed slightly, others under. As long as the
histograms for all photos don’t show any clipping at the black or white
points, you’re OK.
The camera's digital light meter. Zero is optimal exposure.
- Set the Camera ISO setting to a fixed value Some cameras have Auto ISO setting. Per the last point about exposure, ensure you choose a fixed value (eg. 200) rather than Auto.
- Set the Camera to manual focus Most SLR lenses have a switch allowing
you to disengage the motor that automatically focuses your lens before you
take a shot. For panoramics, set it to manual focus (MF). The reason for
this is that as you pan to take each of the shots, the camera may refocus
on something close in or far away, especially if there’s an object in one
of the shots that is prominent. That could result in uneven focus across
the panoramic. Pick one focus setting that works for the whole panoramic
and leave it there.
- Take the Camera out of Auto White Balance Similar to the argument in the last two
points above, you don’t want the camera to change the colour balance as
you pan because of changing content. Choose one of the presets instead of
Auto. For instance, if shooting on an overcast day, use the Cloudy Bright
setting. If shooting an indoor scene under fluorescent lights, use the
Fluorescent setting. If you have access to a photo editing program that
allows white balance adjustment, don’t worry about what preset you choose,
because you can correct all the shots by the same amount if the preset you
chose results in wonky colour.
- Overlap the Photos
Panoramic software uses artificial intelligence to look for
similarities between adjacent shots then join those features seamlessly.
In order to provide those reference points, you need to provide overlap in
content between adjacent shots. I typically overlap by 25%. If I start my
panoramic on the left end then take subsequent shots by panning left to
right, this means that my second photo contains the rightmost 25% of the
first photo. I’ve made marks on my tripod head that tell me how far to pan
before taking the next shot while allowing 25% overlap. I have marks for
both landscape format and portrait formats. But, of course, those marks
only work for one focal length, which brings me to the next point….
- Use a “Normal” focal length For a consumer digital SLR with an APS-C
sensor, normal focal length is about 33mm. Anything shorter is considered
wide angle. The wider you go, the more barrel or pincushion distortion
will be introduced. This may make it harder for the stitching software to
match the photos without twisting the photos to counter this effect. The
more twisting, the more cropping of the final panoramic you’re likely to
have to do. Of course, you could use a longer focal length without this concern,
but remember that depth of field reduces with focal length. I use a 35mm prime lens for panoramics,
adapted from an old film camera.
- Choose the Right Content I like shooting sky panoramics. I found
out the hard way that sometimes the stitching software will not work
properly with some content – particularly soft images with few hard edges.
Some sunset clouds fit that description. Sometimes, it helps to include
some hard edge detail (like treetops) to assist in the stitching. You can
always crop it out later.
- Choose the Right Software I find that the ‘premier’ photo editing package gives too many choices when creating panoramics. You have to try them all to find out which one works best, but my experience is that I generally don’t like any of the results. On the other hand, a cheap and cheerful package sometimes works better and with less fuss. I particularly like ArcSoft’s Panorama Maker, which came bundled free with my point-and-shoot camera.
3 overlapping images stitched together, before cropping. Note how the software has to distort the images to make them match up. |
As you can see, the process of shooting panoramics like a
pro is very manual. If you’re shooting a scene with moving clouds, set up marks
on your tripod so you can rapidly make all your shots before the clouds change
position and shape. And finally, resist the temptation to use more than 3 or 4
shots in a panoramic, because you’ll end up with a long, skinny picture sitting
in the middle of your print that will look silly.
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