Damn close there! It's the integral of the cos of a sin. As best I can do with plain text... Jn(z) = 1 / pi * Integral, 0 to pi of cos[z * sin(t) - n * t] * dt where t is theta. Regards, Bob... -------------------------------------------- "Do not suppose that abuses are eliminated by destroying the object which is abused. Men can go wrong with wine and women. Shall we then prohibit and abolish women?" -Martin Luther ----- Original Message ----- From: "Chris" <nimbo@ukonline.co.uk> To: "List for Photo/Imaging Educators - Professionals - Students" <photoforum@listserver.isc.rit.edu> Sent: Saturday, August 23, 2003 2:01 PM Subject: RE: Minimizing pinhole image falloff - Correction > Thank you. > > We didn't do Bessel functions except in fm radio theory. The theory that I > don't remember involved an approximation. When I tried to do the > integration myself just now I got the integral of the sin of a sin which I > think is the differential form of the Bessel function. Very interesting.
