The term 'reading against copy' often causes confusion, even among proofreaders to whom it refers, so in this article I will try to explain what the term means.

There are two ways in which a professional proofreader may be asked to work: either by reading against copy, or performing a straight (blind) reading.

When he is asked to read against copy, the proofreader will be provided with the author's original typescript (or a copy) with the editor's corrections marked on it, and a set of proofs produced by the typesetter. The proofreader then compares the proofs with the edited typescript, going through both, word by word, line by line, to ensure that the author's text (together with any editorial amendments) has been faithfully rendered, with no errors introduced at the typesetting stage.

When performing a straight or blind reading, the proofreader will be supplied with proofs only and not the original typescript. In this case, the proofreader cannot know whether the original typescript has been correctly reproduced along with the editor's corrections. His job is simply to check the proofs for content, marking up any clear errors in spelling, punctuation, and so on, that he may find.

When reading against copy, most proofreaders operate by scanning a few words of the original typescript, then checking to ensure that these appear correctly on the proofs, with any editorial corrections properly implemented. Where there is a difference (if, for example, an apostrophe has been omitted), the proofreader indicates this with the appropriate mark.

For each correction, one mark must be made in the text itself and another in the margin. This is done in order to ensure that, when the typesetter comes to incorporate the proofreader's corrections, he does not inadvertently skip over any of them.

Errors made by the typesetter must be highlighted with one color pen, mistakes by the author/copy editor with another. This is not in order to allocate blame, but to decide who should pay for the amendments. The standard system of color coding is shown below:

Red: This is used to show mistakes which have been introduced into the text by the typesetter.

Blue: This is used to show errors made by the author and missed by the copy editor, and errors made by the copy editor herself. (NOTE: some publishers prefer black ink to blue -- you will be advised of this when you start working for them).

Green: This color is reserved for the typesetter's own queries or corrections.

The cost of 'red' corrections will be borne by the typesetter, while that of 'blue' corrections will be met by the publisher (or, in severe cases, the author). With a straight reading, of course, you will not know whose responsibility any errors might be. In this case, you will mark up all corrections in a single color (usually red).

As a freelance proofreader you are likely to be offered more straight readings than readings against copy. This is because the amended typescript is normally returned to the copy editor for her to check against the proofs. The proofreader's role is regarded more as providing back-up: a fresh pair of eyes which may see obvious mistakes overlooked by an editor jaded by over-familiarity. Although the amended typescript could be copied and sent to the proofreader as well, in practice this is often felt by publishers to be too much trouble. This may not be an ideal scenario, but it explains why proofreaders are more likely to be asked to perform a straight reading rather than reading against copy.