Anyway, throughout my (now extensive) experience of shooting with expired film, I've learnt some 'best practices' of how to always get usable results out of expired rolls. Read on to find out...
HOW DOES FILM EVEN EXPIRE?
Good question! In the simplest terms possible, camera film is basically layers of chemical emulsion. These chemicals go bad over time, just like the paracetamol in your drawer, or even the food in your fridge, so film brands put an expiry date on all rolls of film. This is essentially a 'best by' date. The film WILL still work after its expiry date, but you cannot guarantee how the results will turn out, as it depends on how much the chemicals on the film itself have degraded.
One of the main things that film will start to do as it ages is become less sensitive
to light. A film's sensitivity is measured in ISO (or ASA on older films) - the higher the ISO/ASA, the more sensitive a film is to light. Higher ISO/ASA films will degrade more than low ISO/ASA films - this is worth bearing in mind when shooting expired film (more on that below).
Some film can also expire in a way that leads to some crazy colour shifts, extra grain, and other weird and wonderful effects. No two rolls of expired film are the same!
This then leads to the next point, which builds nicely on the comparison to food in the fridge - just like food, the process of film expiry can be slowed (or even halted) if the film is stored properly - ie, in a fridge or a freezer. This preserves the chemicals for much longer than if the film is just, say, left in a hot cupboard for 20 years. You may also notice that on many film boxes there will be some text saying something along the lines of 'do not store above 25°C' - this is why! You wouldn't leave a banana out in the sun all day if you wanted it for lunch tomorrow would you?
You'll get much more extreme results with film that has been stored in a hot glove compartment compared to film that has been kept in a nice, cool garage since 2003.
So, film storage is important. But more often than not you won't be able to tell how a film has been stored when you come across it. So how do you get the best results out of expired film?
'ADD 1 STOP PER DECADE' - TRUE OR FALSE?
I'm sure if you've looked into shooting expired film before you would have come across the phrase 'over-expose by 1 stop since the film expired.' I even use this as a simple way of explaining how best to use expired film myself. The basic principle of this method is as easy as it sounds - you simply add 1 stop of exposure per decade since a film expired when shooting it. The easiest way to do this is to set the ISO/ASA on your camera to the corresponding amount of stops LOWER than the expired film's box speed (this is the ISO/ASA of the film when it first came out & will be displayed on the box or canister itself). This then tricks the camera into thinking the film's ISO/ASA is lower than it was when it was fresh, meaning it's less sensitive to light, so the settings it will recommend will correspond to that lower light sensitivity.
You can obviously also add the stops of exposure yourself by setting the camera's shutter speed or the lens' aperture the corresponding amount of stops lower too, but I just found this was much more fiddly than setting the ISO/ASA and shooting away.
Now, as explained above, there are other, more complicated factors that come into play too.
What ISO/ASA is the film? How was is stored? When did it expire? All of these things matter with how to meter expired film properly, and you may only know one of those at a time!
My general advice is - ALWAYS ERR ON THE SIDE OF OVER-EXPOSURE. Not sure how a film was stored? Add an extra stop to be safe. Don't know exactly when the film expired? Add an extra 2 stops to be safe.
EXPIRED COLOUR NEGATIVE/BLACK & WHITE FILM
Over-exposing is a good general rule to follow, particularly for colour negative and black & white films, which can both deal with over-exposure very well if you have slightly over-estimated. As mentioned above, high ISO/ASA films degrade much more than lower ones, so it's definitely worth adding more exposure than you expect to films of 400 ISO/ASA or more.
I spoke to a fellow film photographer the other day who has a rule of 'any expired film over 50 ISO/ASA, I just shoot at 50 ISO/ASA!' To be honest, that's not such a bad idea...
EXPIRED SLIDE FILM
This is where things start to get a bit sketchy (if they weren't already). Slide film doesn't tend to degrade at the same rate as colour negative or black & white film. In fact, it seems to degrade slower. This means that you don't need to over-expose expired slide film quite as much as the others. Plus, slide film has a worse exposure latitude, so it's more important to try and get the exposure as close to perfect as possible.
In my experience, you do still want to over-expose expired slide film, but maybe only add a stop or two at best, particularly to film that expired in the last 20 years or so.
BUT, also in my experience, if a roll of slide film is noticeably expired, it is VERY expired. Expect hella colour shifts and grain, particularly in higher ISO rolls. But more recently expired slide film tends to just look completely normal. It's a lottery!
SHOOTING EXPIRED FILM IN POINT & SHOOT/AUTOMATIC CAMERAS
If you've only got a point & shoot or a camera that automatically reads the film & sets the ISO/ASA for you, there are still ways to get good results from expired film. Firstly, if your camera reads DX codes, you can hack the DX code of your film. This will make your camera automatically over-expose the film.
If you can't do that, honestly the best thing to do is take it outside on a nice, sunny day, and let the sun over-expose the film for you 😅.
Lower ISO films will not normally be a problem, as they tend not to degrade too badly anyway. However, if you have already shot a roll of expired film without over-exposing it, there is something you can do in the development stage to help eke that extra exposure out of the film...
DEVELOPING EXPIRED FILM
I get lots of questions asking if you can develop expired film normally, and the answer is YES (unless you've inadvertently shot a roll of film that uses an obsolete chemical process like Kodachrome), but almost all of the time you can develop expired film completely normally.
If you've already over-exposed your film when you shot it, there's nothing else you need to worry about, and you can send it off to a lab or develop it at home yourself and sleep soundly in the knowledge that you did everything right.
If, as above, you were unable to over-expose the film when shooting, you can ask for/do something when the film is getting developed known as pushing. All this really means is that the film gets developed for slightly longer, but by doing this you can actually add a stop or two of exposure even after you've shot the film! If you're sending it off to a lab, simply ask them to push the film by a stop or two in development. Most labs will do this for you no problem, although some may charge a small extra fee.
For everyone who couldn't be bothered to read all of that (don't worry, I'm one of those too 😂) here's my summary of how to get the best results from expired film:
- Over-expose from film's box speed (1 stop per decade since expiry is a good rough rule for films of 400 ISO/ASA or lower, but try to find out how the film was stored). I do this by lowering the ISO/ASA on my camera. If in doubt, always add an extra stop!
- Higher ISO/ASA films will degrade more extremely than lower ISO/ASA films, so adjust your over-exposure settings accordingly
- Most expired film can be developed normally
- If you couldn't over-expose when shooting, push +1 or +2 stops in development
- Colour negative and black & white film degrade quicker than slide film, but deal with over/under-exposure much better
I summarise all of this in a little more concise manner in this video, have a watch if you'd like to see me explaining how I'm shooting a roll of expired film as I do it:
Thanks so much for reading! I really hope this was helpful.
If you have any questions at all, please let me know in the comments of this post, or you can DM me on Instagram.
Happy expired shooting!