I first learned that CS5 had the ability to do this through Luis who was displaying some of his work as part of First Friday at Loft 121 Number 5 along with me. I first tried this at the Steven F. Udvar-Hazy Center near Dulles, and it came out ok (I included the photo below as reference). This time I merged a total of 7 shots, instead of 3, to make the curvature less noticeable. I am very pleased with the Photomerge results, and it saves me having to purchase a fisheye lens for quite some time!
Back to the processing, I used Digital Photo Professional (which comes included with Canon DSLR cameras) to export the RAW images at -2, 0, and +2 to create the files that I would use to process the photos. I imported each group of photos (all 6 at -2, all 6 at 0, all 6 at +2) and used Photomerge to create a panoramic shot for each group. I then resized each panoramic shot based on the smallest resolution (which was 10832 x 2663) and loaded them into Photmatix to create an HDR image.
Photomatix does an excellent job removing ghosting and matching structures, whereas HDR Efex Pro does not so I only used the result from Photomatix in this shot. If you look closely you can see that the Tower of Americas does not quite line up properly and you may notice ghosting on the road from the vehicles. That is a result of overlapping and imaging sizing difference from different shots in Photomerge and unfortunately is unavoidable without purchasing a fisheye lens.
Once I got a result I was happy with it was loading the image into Photoshop and tweaking the coloring and lighting like any normal shot, except this one was really wide. I am pretty pleased with the result from the processing. One word of caution though, if you are using the Photomerge option make sure you have a pretty beefy processor and lots of RAM because you are definitely going to need it!
(PS: I know the images bleed into the column to the right a little bit, I did that on purpose so if you only view it on the blog instead of clicking it and seeing it in the smugmug gallery you can make out more of the details)
Panoramic view of San Antonio (via Photomerge in Photoshop CS5)
First Panoramic stitching attempt: Steven F. Udvar-Hazy Center