Here's a quick comparison I did of the cameras in the 1st generation iPhone and the 4th generation. Both photos are unmodified, other than that they were re-sized and put together in Photoshop.
The main difference you aren't seeing is the size of the images, since the 1st gen has only a 2 megapixel camera, while the iPhone 4 has a 5 megapixel. You can see that the iPhone 4 has much crisper colors and pulls in more details of the fruits and veggies.
Here are the originals, unresized : iPhone 4 and iPhone 1. More Green Market produce pics here.
Yeah!! these pictures clearly distinguishes between iPhone 1 and iPhone 4. Thanks for this…