Issue for timeout when capturing an image

[vinhcp]

@vitalie I have an issue to capture the screen from redirected url. Here is my case: I have plan to capture an url and it also takes us to another url. I see it works well on local machine and capture the destination screen successfully. But when I pushed to server (using heroku) and after I entered the url, the screenshot was not captured immediately. The fact is that there is a timeout to capture screen, I mean I should set timeout about 10s to wait the page loaded and it will be captured exactly. Why this one run in a different way between local machine and server?