two cameras simultaneously on a gui / timer issues

Dear all, I am building a gui with guide and I need to have two axes running live videos simultaneously and controlled separately. The videos are actually series of images in a while loop. After searching a bit, I think I could use timer to do that. Unfortunately I have problems implementing it, it keeps giving me an error - too many input arguments and I don't understand why. Below is the part of the code, as clean as possible, with the while loop and after that the one with the timer.

function pvideo_Callback(hObject, eventdata, handles)
%...
%functions to set camera/sensor parameters
%...
handles.Stop=0;
guidata(hObject, handles);

while gstatus==20072
    [returnCode,video]=GetMostRecentImage(xpixels*ypixels);
    for fil=1:ypixels
        for col=1:xpixels
            im1(fil,col)=video(xpixels*(fil-1)+col);
        end
    end
    axes(handles.lucvid),imagesc(im1), colormap gray

end

Here is a try with the use of timer

function pvideo_Callback(hObject, eventdata, handles)
%...
%functions to set camera/sensor parameters
%...

handles.timer1 = timer('ExecutionMode', 'fixedRate','Period', 1, ...
  'TimerFcn', {@Luca_Frame_Callback,hObject, handles});
start(handles.timer1);
guidata(hObject,handles);

function Luca_Frame_Callback(hObject, handles)

      [returnCode,video]=GetMostRecentImage(xpixels*ypixels);
      for fil=1:ypixels
          for col=1:xpixels
              im1(fil,col)=video(xpixels*(fil-1)+col);
          end
      end
      axes(handles.lucvid),imagesc(im1), colormap gray

[Sean de Wolski]

Have you tried using the Image Acquisition Toolbox? It provides some of the framework for you.