Hi guys,

I am doing some FLIM, detecting single photons for creating a histogram of counts against time (Time-Correlated Single Photon Counting).

What I am doing now is fitting my decays doing the convolution with the IRF. The problem is the shift, there is a time shift I need to correct. What I do is an interpolation in order to get more data points and I align the highest slope of the IRF with my intensity decay, and I think after that I should undo the interpolation and come back to the raw data, with the IRF moved. From there, I am moving the IRF around the intensity decay peak and I choose that fitting that gives me the closest value of ChiSq_r to 1.

I know there is a way to do the shift, but I am not able to understand it. I am having a look at a FORTRAN code (which I am not familiar with), from the David Phillips book (Time-Correlated Single Photon Counting), but I am not able to understand the background, I am missing the key point.

I am using MATLAB, and I would really appreciate a hand on it. I need to do it for my whole image and then with anisotropy measurements, I will do the same for getting the rotational correlation time. That is why I want to do it myself.

Many thanks!