A year ago I bought the Canon Powershot S3 IS after comparing about ten different cameras and driving the Best Buy staff to distraction. I mainly chose the S3 for its 12x optical zoom and Stitch-Assist (panorama) function and right there ends my entire repertoire of digital camera jargon.
The Stitch-Assist has been easy to use in conjunction with Photoshop’s Photomerge function, though there are other panorama options to explore like PTGui which this guy has used to great effect. This weekend I used Photomerge to blend some photos I took of my town (click to enlarge):
Getting Started with Photomerge
Import all the individual pieces of your panorama into Photoshop. Then select File->Automate->Photomerge. The software will attempt to blend the photos in a way it thinks makes sense. To the human eye, the result is never quite perfect. You can select the “Advanced Blending” option, but you’re still going to get mismatched colors and alignment issues like this:
Do It by Hand
For me the best panoramas are mostly achieved by hand; (same goes for the Pen Tool when making cut-outs). Editing by hand requires the layers to be preserved individually instead of flattened. So with the Photomerge dialog still open, check the “Keep as Layers” option and hit OK.
Line Up the Edges
By now, Photomerge will have lined everything up as best it can, but inevitably the layers will be off by a few pixels. The shape of the lens and curvature of the earth work to your disadvantage here. So use the Move tool to push the individual layers around til they line up, resizing them when necessary or rotating them via Transform->Rotate.
Blend the Sky
Clouds and sky can be difficult to blend convincingly. In this situation, I usually select the topmost layer and add a layer mask. Then with the lasso tool I make a selection around the trouble spot, feather it by about 25px, and fill it with black, aka, temporarily deleting it:
Before:
After:
Final Levels and Curves
The last thing I do is create Adjustment Layers for Curves, Hue & Saturation and Levels. I place them at the top of the layer stack to ensure all the images are affected equally and evenly.
So Far, So Good
There are a million ways to do this – I’d love to hear suggestions for other stitch-assist software or blending methods. I’ve been finding it fun to use panoramas exclusively while on vacation; it makes looking back on places you’ve been, viewed at 180 degrees, a much more vivid experience.
