When I got my tech license, I tried using a picture I took on my digital camera that was supposed to be adequate for passports. Big mistake. Our lovely Board of Pharmacy ended up sending my application back and requesting a new picture, and I spent my first week & a half as tech unable to do anything except unload freight and cashier because I didn't have my license yet.
I don't know if every state is as picky as Oregon's Board of Pharmacy apparently is, but I think paying the $8 to get a passport photo is worth saving yourself the frustration.