Pushing & Pulling film
What does it mean to push, or pull film? To put it simply, it's shooting a roll of film at an ISO different to its box speed; a technique that provides you with more flexibility when you're out and about. Most of the work with pushed and pulled film is done in the development stage, but we're going to take you through everything you need to know - it's easy to start doing and is a really useful technique to have in your arsenal.
The technical part
Film is pushed in stops. Each stop represents a doubling of the film speed. So a 200 ISO film pushed one stop (+1), will then be rated at 400 ISO. Pushing it two stops (+2), will take it to 800 ISO.
When you are pulling film, each stop halves the film speed. So pulling one stop (-1) will take a 200 ISO film to 100 ISO and so on. You typically don't want to push or pull more than 2 stops, and a lot of labs won't develop films that have been pushed further than this.
It is critical to keep a note of how many stops you pushed or pulled a film. You can write on the film roll, or even put a sticker on to remind you. The most important step of pushing and pulling film comes when it is being developed, so make sure you let whoever is developing your film know!
A shorter development time (pulling) will reduce the density of the highlights and the contrast of the negative. An extended development time (pushing) will increase the density of the highlights and therefore up the contrast. This changing development time will counteract the over or under exposed film.
Pushing works really well with traditional black and white films like Tri-X and Ilford HP5. When it comes to colour, professional stock like Kodak Portra or Fuji Pro 400H tend to stand up to this technique better than the more budget options.
- Pushing is when you shoot a film at higher than box speed.
- This means you are giving the film less light, and underexposing. To make up for this, film that has been pushed will need a longer development time.
- This will give your final images more contrast and grain.
- With colour film it will also increase the saturation.
Ektar 100 shot at 400 ISO (+2). Illustrates how a low ISO film can be pushed to be used on a darker, more overcast day. Notice the high contrast and how the colours feel punchy and saturated.
Increased film contrast, more grain and a lightened image. Bright areas become lighter, but shadows will stay more or less the same.
- Pulling is the opposite, where you shoot a film at lower than box speed.
- In this case, you are overexposing, and giving the film more light, this also will need to be compensated in the developing process.
- This results in reduced contrast in your photos.
These photos were taken on a sunny day, when the photographer only had access to a roll of Neopan 1600 film. By pulling it two stops and shooting at ISO 400 he was able to adapt to the lighting conditions, still use the film, and get some great photos.
Less contrast, darker image, pulls more detail out of the shadows. Be careful on grey days, as it can produce a more flat and dull negative.
How it's done
It's simple, quick and easy to push or pull. Just set the ISO of your camera to the speed you want to push the film to. Take photos as normal, then when you send your roll to be developed, let them know how many stops it was changed by. The lab will do all the rest of the work for you.
Photo by Parallax Photographic Coop
When and why should you push / pull ?
- Practical - Pushing and pulling film allows you to adapt to changing lighting situations. This is especially useful if you are out with only one roll of film. If you find yourself in low light conditions, you can push the film to help you get a better shot, or if it's a really bright day, pulling will allow you to shoot the roll at a lower speed.
- Aesthetic - The creative effect of pushing and pulling is not to be ignored, it can change the contrast, saturation and grain, leading to even more variations with different types of film.
- You forgot to change the camera speed - It happens to all of us, you've forgot to change the settings and you shot 400 ISO at 100 - don't fear! You haven't lost your photos, you can push it two stops when you develop, and your photos should still be fine.
Cover image by The Darkroom
Author : Becca Knight