Here you'll find the steps needed to make the macro lens to fit on you Otterbox Commuter Series case.
You'll see that this is a lens from a film\darkroom enlarger. You can do a search on ebay for an Anastigmat lens. Here's the full name of the lens I used for this project
Anastigmat Fedar Enlarging Lens 3.5" 90mm F6.3 on mounting plate
This is just a shot of the back side of the plate
First, remove the plate but turning it counter clockwise. It spins off rather easily.
Next, remove the three screws shown here. (You'll need a small or precision screwdriver)
Once you've separated the parts you're going to use the second lens found screwed into the bottom half of the full set.
This will be the result (almost there)
You'll need to take this lens apart for the last time,
Screw the ring off of the bottom by turning it counter clockwise. You'll find a small glass lens, take it out, and leave it to the side
Take the ring and super glue it to your Samsung Galaxy S3 Commuter Otterbox as shown. Press down firmly on it for about 2 minutes and let it dry over night
* Don't use generic super glue, it doesn't hold. Get locktight or something along those lines.
DO NOT DO THESE STEPS WITH YOUR PHONE IN THE OTTERBOX. REMOVE YOUR PHONE BEFORE GLUEING
Screw the lens on the ring (now your mount)
Here is a photo of a French Fry and the end of a banana