Judging the condition of a movie poster is obviously something that you should be able to do, especially if you're buying off an internet auction site such as Ebay. If you're buying from a shop you can see the condition yourself, but you should still have an idea of what to look out for in terms of any defects that could affect the future value of the poster. On this page I will go through a few of the basic things to look for when buying a poster.
One quick note first on grading. A lot of people use different scales for conditioning movie posters but usually it will go something like:
Where Mint is totally unused and Poor is pretty much destroyed. Near Mint will usually be as good as you'll get, but Excellent and Very Fine are more typical and should still indicate a poster that is still extremely presentable.
'Good' may sound good, but usually means 'well worn'. Although not worthless, a poster in this condition would have to be quite old and valuable in the first place to justify any attention.
It's worth noting also that some places will grade harsher than others, emovieposter being one example. You'll rarely find them selling a poster graded better than Very Fine, but that Very Fine would often be graded Near Mint by other websites.
The best thing to do in any situation is to use your own eyes to grade the item. Unless you can trust the seller then it's always best to assess the grade yourself with whatever information you can obtain.
Unless you're buying a recent poster, or one printed on card stock (e.g. US 30x40 or 40x60) then the poster will most likely have been machine folded for distribution. The simple process of unfolding such a poster will cause damage along the fold lines and especially at the central fold joints (where horizontal and vertical folds meet). This damage is pretty much unavoidable, but the degree of wear will affect the value. Older posters which were printed on a fairly matt stock can appear to have little or no wear, but more recent glossy posters can exhibit more obvious fold line flaws.
Linen (or paper) backing will flatten out any poster, but fold wear will sometimes require restoration depending on how much it detracts from the overall image. (See my section onLinen backing for more information). This can be costly, so when you buy make sure you understand the costs involved if you want to have this done.
Personally I think that some light fold wear can add to the charm of an old poster. Vintage artwork that has been completely restored can look too good!
I've created a section on border damage (separate from any damage to the main image) because the negative effect on the value is quite different. A 1-inch tear on an outer white border of a poster is fairly insignificant, but a 1-inch tear right in the centre of the main image IS significant and more expensive to restore.
Typical border wear you'll come across will be pinholes / staple holes, small nicks/tears, tape stains, minor paper loss and possibly writing of some kind. The odd pinhole or small tear is not usually a problem; they don't distract you from the main image and they'll probably disapear if you choose to linen back the poster. However defects like tape stains and paper loss are more significant as they require restoration to correct.
Any defect in the main artwork (apart from fold lines) can have a significant effect on the commercial value of any poster. What you have to look out for is anything that is noticeable enough to draw your eye away from the overall artwork. Restoration can repair a lot of things easily (e.g. minor surface wear, tears with no paper loss etc..), but obvious major flaws should be avoided unless you're willing to pay for a professional to reconstruct the poster. By major I mean something like the following:
Most of the defects above can all be fixed in one way or another through linen backing and careful restoration. But the one thing that can't be corrected for (except at great cost) is fading. Any poster left exposed to bright light over its lifetime will fade, especially if that light was UV in the form of sunlight. Once the colours have faded, that's it. The linen backing process can brighten up colours, but only up to a certain point. If a poster looks faded in anyway (e.g. tanned border instead of a white border) then it's probably been left exposed to bright light for too long, and such tanning is a sign that the paper isn't going to be in great condition due to the chemical breakdown taking place inside the material.
However, be careful not to mistake a badly photographed poster for a faded one. And similarly, a picture of a poster taken with a bright flash can show it to be more vivid than it is in real life.