My First Stitched Panorama

In the last weekend, I join an outing around the Esplanade area. I tried in taking multiple picture through a 360 degree and see if I can stitch them into a 360 degree Panorama. This is my first attempt. I put the camera into manual exposure. Though I forgot to put it into manual WB. The picture below is actually using auto white balance. I turning around a virtual center which suppose to be the first element of the lens. I was using a sigma 10-20mm at 12mm f/5.6 in landscape orientation. As a aftermath, there is some vignetting at the corners. I should use a longer focal length, say 20mm at f/8, may be in portrait orientation instead. Well, this is my time, learn from the mistake next time. The stitching is done in Photoshop CS3. I use the auto mode and it works quite well. A total of 6 photos are taken.