The general condition of a collectible document is a main factor of its value. The condition mostly depends on its age, the use of the document and its proper preservation.
For example, it is common that movie posters and lobbycards present some pinholes or small piece of tape on a corner, knowing that they were displayed in movie theatres. It is also common that folded movie posters present slight fold lines, knowing that it is easier to store posters folded, which is fine but can create heavier fold wear if not preserved properly (opened/closed a lot, heavy weight on it, acidity, humidity, heat…). It is also common that the paper of older movie posers tends to turn a bit yellow with time, meaning that older documents cannot be graded as “mint” document (on our website…), even if they are in a pretty good condition otherwise.
Several grading systems exist to detail movie collecible condition. At www-mauvais-genres.com, we choose to use the "10-grade system", which was introduced by Jon Warren and is patterned after other collectible hobbies, such as comic books. Grades range from C1 to C10 and are detailed below.
C10 - MINT - For us, the grade "New" (C10) corresponds to a document that has never been handled and cannot be applied to vintage movie posters! Hence the virtual absence of this grade on our website for vintage movie posters and vintage documents.
C9 - NEAR MINT - Superb. Condition of an unused or very carefully used movie poster, which may have very slight storage defects, slight compression marks are allowed in this grade, due to display in movie theatre. The edges should not fray. The ink must not have been significantly broken by the folding.
C8 - EXCELLENT - A poster whose condition is above average and which shows very slight signs of use. The object should not have any major flaws but may have a series of small flaws, such as a few pinholes, discoloration on older objects. No writing of any kind on the front of the item, but possible on the back as long as it does not bleed on the front. No scotch allowed. Clean. The imaged part must not be damaged. The edges should not fray. No missing piece. Folds at the corners are allowed.
C7 - VERY GOOD to EXCELLENT - A very well preserved movie poster, close to the C8. A few transparent scotches are tolerated at the front if they are not on the main visual, some minor traces of humidity, tacks, a few light tears, slightly marked folds. At first glance, the object should appear in very good condition.
C6 - VERY GOOD - This grade is the most common grade for movie posters that have been used “normally” by movie theaters. The visual must be clean but defects may appear on the object: small tears on the edges, pronounced folds or several pinholes, tape, slight tears, small pieces missing on the edges, folded corners, etc. An object cannot be classified in this grade if it has excessive defects.
C5 - GOOD to VERY GOOD - A heavily-worn item, showing significant signs of use such as multiple pinholes or staple holes, tape, tears, soiling, pieces missing, small markings or pen/pencil marks. Although this is an "in-between" grade and difficult to distinguish from a C6, items are relegated to this lower classification when there is a greater number of general flaws than would normally be expected in the higher grade, or when one major flaw makes the C6 grade unacceptable.
C4 - GOOD - Below average but still suitable for display. Heavily used, with significant signs of use that affect the overall eye appeal of the piece. Small pieces may be missing from the borders (should be described). Image area will usually have minor defects that may impinge upon the graphics. Could have tape, writing, or tears. Numerous pinholes and resulting tears could be present. Complete, but graphics are face-worn.
C3 - FAIR - Often referred to as Fair condition, or Condition D. Heavily worn, but yet still complete
C2 - POOR to FAIR - An extremely worn, possibly even incomplete item.
C1 - POOR - The lowest grade, representing items in the lowest possible condition. Heavily damaged, possibly missing large pieces, possibly brittle and crumbling. Except for valuable rarities, items in this grade have little or no value.
Information courtesy of LearnAboutMoviePosters.com (Thanks Ed !)