There are several ways to access the quality of optics. One simple approach is to take photos of a test chart. But this requires a high quality print of the test chart.
Here are two prints that a friend made for me with a very good ink jet printer and laser printer.
The photo above was taken with an iPhone4 (no tripod) and includes some nasty reflections. The laser printer is a Fuiji-Xerox DCC 360 and the injet printer is an Epson 118880. The charts are printed on A3 sheets, the laser using a matt card and the injet using glossy photographic paper.
Bellow are a couple of closer shots so we can see the details of the printing (still no tripod). These are large images so if you do click on them it may take some time to download.
Looking closely it is clear that the laser printer does a better job. The laser printer has a claimed resolution of 1200x1200dpi while the injet claims up to 2880x1440dpi This was a big surprise for me. My friend mentioned inkjet resolutions are often over stated because of ’spray-drift’ or basically the ink splattering onto the paper.
Next step will be setting the laser printed chart up with a tripod so we can get higher quality photos possible with the iPhone 4.
You can download this chart in PDF format.