Using timer to capture images from webcam

Hi,I have a question. I want to use a webcam to capture an image every 1s.I made a GUI with 2 axes and 2 button.Axes 1 is used to show video from webcam and axes 2 is used to contain images that I capture from axes 1.Button 1(start) callbacks the function of starting recording from webcam and button 2(capture) is used to activate the timer.I tried this code:

function start_Callback(hObject, eventdata, handles)
 global vid
 imaqhwinfo;
 info=imaqhwinfo('winvideo');
 vid = videoinput('winvideo', 1,     info.DeviceInfo(1,1).SupportedFormats{1});
 vidRes = get(vid, 'VideoResolution');
 nBands = get(vid, 'NumberOfBands');
 hImage = image(zeros(vidRes(2),vidRes(1),   nBands),'Parent',handles.axes1);
 preview(vid,hImage);

function capture_Callback(hObject, eventdata, handles)
% hObject    handle to capture (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
global vid
handles.t=timer('ExecutionMode','fixedRate' ,'TimerFcn',  {@TimeUpdate,handles},'Period',1);
start(handles.t);
set(gcf, 'DeleteFcn', {@DeleteFcn, handles.t});

function TimeUpdate(obj,eventdata,handles) 
 global vid
 axes(handles.axes2)
 start(vid); 
 im=getdata(vid,1);  
 imshow(im); 
 guidata(hObject, handles);

function DeleteFcn(hObject, eventdata, t)         
 stop(t);
 delete(t); 
 clear all;

The problem is I just can capture image only one time when I push capture button and after that nothing happened(there are no new images appear in axes2).I tried to increase the Period to 5s and remove this row: axes(handles.axes2) in TimeUpdate function and the GUI run correctly but images is no more stored in axes2.But I want to store image in axes 2 and the Period is still 1s or less.Can you tell me how can I do that. Thanks a lot.