Factual questions are What-questions (or who/where/when-questions): they are extremely useful but they must be understood as being nothing more than a first step. Factual questions are important also as they encourage - demand! - close-reading skills.
To observe a text is to read it closely, picking out on facts and details, accumulating material to think from and with. So if in a text there is a character named Mary, and she decides to marry a man, a factual question could simply be:
Who is Mary's husband? Who did she marry?
Other factual questions would typically be like:
Where do they live? How old is she/he?
Factual questions start off the process of thinking about what there is in a text, in order to draw connections between what we find. You could call it 'analysing the text', but that, in itself, can only be an initial step - analysis is not interpretation. The important point is to use what factual questions deliver, and make links between the who, where, what, when and whichever other fact we found. in our example above, Mary could be twenty-five or forty-five; she could live in a big city or in a village; it could be now, or fifty years ago; her husband could be younger or older. All those elements, in isolation, mean very little: they acquire meaning in their relation with one another because each of them slightly modify the meaning of the other, and thickens the reality of the characters and of their lives.
Make sure not to turn your questions into 'novel-check' questions only, where it seems that the only purpose for those questions is to check that someone has read the text. Factual questions elicit objective answers, and must be used to full the subjective part of reading: interpreting.