How to Push Film (and Pull It): Stops, Lab Fees and Dev Times

Pushing film means rating a roll at a higher speed than the box says, then developing it longer than normal to make up for the underexposure. The Darkroom puts it plainly: pushing and pulling only happen in processing. If you shoot at a higher ISO and the roll gets normal development, it is simply underexposed.

The number you set is called the exposure index (EI). The film's real speed does not change; you are telling the meter to give it less light. Some guides, including The Shutterbug and Analogue Wonderland, call the higher ISO setting itself the push, which is where a lot of the confusion starts. In practice you need both halves: the higher setting in the camera and the longer development.

Pushes are counted in stops. A stop doubles or halves the light, so each doubling of the ISO setting adds one stop of push: ISO 400 film shot at 800 is +1, at 1600 is +2 and at 3200 is +3. Pulling runs the other way, so 400 film at 200 is -1. If ISO numbers are new to you, start with film ISO explained.

The usual reason is light. The Darkroom suggests a push when, at box speed, you cannot keep the shutter at 1/60 second or faster handheld with an SLR, or 1/30 with a rangefinder. Dim interiors and night streets are the typical cases. It is an old trick: Andy Warhol's 1965 film Empire was shot on ASA 400 Tri-X 16mm and pushed to ASA 1000.

The second reason is the look. A pushed roll has more contrast, more saturation on color film and more visible grain, and some photographers rate film higher on purpose to get exactly that.

If there is enough light, The Darkroom recommends not pushing at all, because box speed usually performs best. Harsh, contrasty light is a poor match too: The Darkroom says a push makes it harder to keep highlights from blowing out and reduces shadow detail.

Longer development builds up the highlights and midtones while the shadows and blacks stay about where they were, according to The Shutterbug. That is why contrast climbs with every stop. Shoot It With Film lists the side effects: more contrast, more saturation, more grain and possible color shifts.

A push is not a free ISO upgrade. A 400 film shot at 800 and pushed will not look as if it was shot at 400, and Analogue Wonderland notes that Portra 400 pushed to 800 will not necessarily look like Portra 800. Pushing also cannot bring back shadow detail that never reached the film.

Color negative tends to over-saturate when pushed and under-saturate when pulled. Underexposed color can show greenish shadows and off-color skin tones, per The Darkroom. A 35mmc writer who shot Portra 400 at EI 1600 (+2) saw an occasional yellowish cast and a slight color shift in the shadows, which was easy to remove in Photoshop.

One stop is the most common and dependable push, according to Unique Photo, and Glass says color negative usually handles it with modest shifts in color and contrast. Three stops is possible with some black and white films but costs shadow detail, and Analog.Cafe calls anything past three rare.

Manufacturers set the official limits in the table below, and owners often go further. Ilford stops at +3 (EI 3200) for HP5 Plus, yet a Shoot It With Film contributor who pushed it 3, 4 and 5 stops says they would feel comfortable going 3 or 4, and Emulsive found that even 5 to 6 stops (EI 12800 to 25600) work surprisingly well for a traditional-grain film. Kodak is more conservative with Tri-X 400, listing EI 1600 as its maximum.

Contrast matters as much as speed. The Darkroom finds lower-contrast films like HP5 and Kentmere 400 push very well compared with Tri-X, which starts out more contrasty.

Slide film is where sources disagree. Glass says it responds poorly and is rarely pushed more than a stop. The Darkroom says E-6 is the least common film to push but can be pushed with good results, and shows Provia 100F shot at 200 (+1).

To shoot a pushed roll, you need a way to tell the meter the new speed: a camera with a manual ISO dial, exposure compensation (set -1 for each stop of push, per Analog.Cafe), or a handheld meter. The camera's ISO setting only feeds its built-in meter, so if you use a handheld meter, set the EI there instead.

Many 35mm compacts read the DX code on the cassette and do not let you override it, as 35mmc points out, so check your camera before you plan a push. 35mmc also explains how some photographers recode the DX contacts.

After that, you need a marker for the cassette and either a lab that pushes your type of film or home chemistry with a known push time. At home the push itself costs nothing extra: the film just stays in the developer longer. As of October 2026, the CineStill Cs41 kit costs $32.99 for up to 24 rolls, about $1.37 a roll if you use all 24, and Df96 costs $19.99 for 16 or more rolls, $1.25 a roll or less.

At home, pushing is no more complicated than normal development: the film sits in the developer longer and every other step stays the same, as Shoot It With Film puts it. Glass gives 30 to 50 percent more time per stop as a starting point, but the film's data sheet has the exact figures. For the full process, see how to develop film at home.

Black and white example: the Ilford data sheet times quoted by Shoot It With Film for HP5 Plus in DD-X diluted 1+4 at 68°F are 9 minutes at box speed and 20 minutes at +3 (EI 3200). Ilford does not recommend pushing HP5 Plus past +3 or give times for it; the Shoot It With Film writer used 35 minutes for +4 and 55 minutes for +5 in the writer's own tests.

Color example: CineStill recommends 102°F for its Cs41 kit, and an Emulsive writer's chart for the kit, which does not state a temperature, gives 3:30 for fresh chemistry at box speed, 4:33 at +1, 6:08 at +2 and 8:45 at +3. That is about 30% longer for +1 and about 75% longer for +2 (6:08 against 3:30). CineStill also asks for 2% more time per roll already processed in the kit.

A 2005 Photo Forum thread gives a rule of thumb for other C-41 chemistry of about 30% more developer time for a one-stop push, and for E-6 slide film, 130% of the normal first developer time for one stop. With CineStill's Df96 monobath, you push or pull by adjusting the temperature instead of the time; CineStill's example is adding 10°F to push P3200 or Delta 3200 to 3200.

Pulling is the reverse of a push. Rate the film slower than box speed (400 film at 200 is -1), mark the cassette -1, and have it developed for less time; in the Emulsive Cs41 chart, -1 is 2:45 instead of 3:30 at box speed. According to The Darkroom, pulling reduces contrast and brings out detail in the shadows, and most people do it in sunny, bright or high-contrast light.

It is almost always done with black and white. The Darkroom says pulling color film can be done but is not recommended, and it also mutes colors and flattens the image. Color negative tends to under-saturate when pulled, and Reed Photo in Denver no longer pushes or pulls C-41 at all.

Often you do not need a pull. The Shutterbug says pulling is often deemed unnecessary if you overexposed by one stop. If you overexposed on purpose, say 400 film at 200, and want normal development, you do not even need to tell the lab.

These mistakes come up in the lab guides and photographer write-ups listed below.

• Forgetting to tell the lab. No lab can tell from the cassette what you rated it at, and a pushed roll developed normally comes back underdeveloped; Brooklyn Film Camera calls it 'thin and unfixable'.
• Marking only the order form. State Film Lab says it cannot guarantee a push or pull unless the roll itself is marked.
• Changing the EI mid-roll. Development applies to every frame, so shots at ISO 400 and 1600 cannot share a roll.
• Underexposing the pushed roll too. Underexposure is the most common mistake The Darkroom sees on regular and pushed black and white film. A push raises highlights and midtones but cannot add shadow detail, so meter at the new EI and protect the shadows.
• Assuming every lab pushes color. Reed Photo dropped C-41 pushing, The Shutterbug in Oregon does not push in-house, and a 35mmc writer found a lab willing to push C-41 harder to find than expected.

Match what you see on the negatives or scans to the likely cause. Development happens once, so most fixes apply to the next roll rather than this one.