I decided to give Photoshop a try - and even though it took couple of hours to process the images, it finally came up with a gigantic 112 mega pixel image.
My next dilemma was how to present this image to others. The file is 22,885 pixels wide and 4,885 pixels long. Obviously, viewing such a large image on a standard 800 x 600 screen would not provide the ideal experience as the user has to scroll up and down to view the details in the image.
There are couple of solutions available for presenting large images to the end user. Zoomify provides a simple application that allows you to feed the application with the large image and it spits out hundreds of tiny images and presents them interactively using a flash-based application. I tried the free version of zoomify with my original (half-sized) image and uploaded it to one my my websites. The result is pretty interesting as you can see it here.
A friend recommended Seadragon - a cool application from Microsoft Live Labs. To implement Seadragon, you first upload the image to any image hosting website (I used my normal Flickr Account) and then give the URL to Seadragon, and it comes up with a interactive version of the image that the user can zoom in and see the details.
I love Seadragon since it's very easy to implement and the result can be embedded directly within your blog/website.
This is my Seadragon implementation of the final image. Click on the (+) and (-) buttons to zoom in and out of the image. You can also use the scroll bar of the mouse for zooming.