Helping a friend debug a PHP error on a hosted site. A certain operation (building a large PDF) causes an Error 500. Running same operation offline doesn't throw error. A larger PDF (running different code) succeeds. How can I debug this error? I can't find wherever the hosting provider hid apache's error.log. I don't think I have global write access to php.ini. I definitely don't have root. Can I trace the app or trace apache somehow?