Why does a film expire? What's the difference between expired film and fresh film? You'll find the answers to these questions and more in this Tipster!
Here in the Lomo world you hear about expired film A LOT, and it is something we all want to or have tried. The ones who haven’t tried it can be afraid of buying something that supposedly doesn’t work anymore, but is it true that expired film doesn’t work anymore? I don’t think so.
First, I’ll tell you why the film manufacturers put an expiration date on the film and for that I have to explain you the nature of the emulsion.
When a film stock is produced (which can contain many film rolls) it is made to achieve certain sensibility (or speed), a.k.a. ISO (or ASA); it can be 400 ISO or 100 ISO or 800 ISO. Then it gets out of the factory and sent to the store for people to buy it. There’s no way for you as a consumer to know how the film was transported or stored before it arrives to your hands, and depending on those conditions (temperature, lighting, humidity) the film can lose a certain amount of sensibility. That’s why you can sometimes buy a film rated 800 ISO but in reality its sensibility is 400 ISO. This can be a lost of one step, and sometimes you don’t even notice it.
Now, the date the manufacturers use as expiration date is the one they can assure the film to not have lost a lot of its sensibility and in a way to still be the one printed in the package. After the day the film expires, the manufacturer is not responsible of the problems you may encounter when using it, but the emulsion still works properly. The thing is, it is less sensible.
The main difference between fresh and expired film is that when using fresh film you can trust in its native ISO value and when using expired you can’t.
So, there’s no problem when using expired film and the only thing you have to take into consideration is that you’ll need more light than stated. If you buy a roll of film that expired two years ago and it is supposed to be 400 ISO, maybe you should shoot it as 100 ISO. Knowing that in advance, you won’t have problems using the insanely fun expired film and the results will be great. And what are the effects on the image when using expired film?
Well, you get more contrast and intense colors. Also, the colors can change a little bit. For example, If you had a light blue it can get a bit of purple; but this isn’t always true, they can change in different ways or they can stay the same. This is what makes expired film so exciting, the results may vary from one to another and the results can really surprise you!
Don’t be afraid to experiment with expired film! You’ll love it!