get upper and lower limit from imcontrast

I'm using imcontrast to adjust the histogram of one image, once I'm satisfied with the result, I would like to apply the same transformation to a set of images. I'm using multiple callbacks so the Idea is to get the limits pass it on to the next callback and use imadjust to do the operation. here is my code so far   if true function adjust_contrast_Callback(hObject, eventdata, handles) axes(handles.axes1); h = imshow(handles.I); dbh = imcontrast(handles.figure1); set(dbh, 'CloseRequestFcn', @(s,e)getValues(s)) waitfor(dbh); I = get(h,'CData'); handles.I = I; imshow(handles.I); end %the callback function for when the user closes the imcontrast window function getValues(dbh) window_min = str2double(get(findobj(dbh, 'tag', 'window min edit'), 'String')); window_max = str2double(get(findobj(dbh, 'tag', 'window max edit'), 'String')); contrast = [window_min window_max]; handles.contrast = contrast; I'm able to get the values but I can't close the imcontrast window anymore, I tried close() didn't work... anyreason why would this happen? thank you!