Does the format change the depth of field?

Yes, at the same framing. A larger frame needs a longer lens for the same view, so the background falls away faster. A 4x5 at f/5.6 separates a face more than a 35mm frame does at the same f-number.

Is 35mm a lens or a frame size?

The word does both jobs. A 35mm lens is a focal length that sees moderately wide. The 35mm format is a frame 36mm by 24mm. The cinema catalogue covers the lens, and this page covers the frame.

Can I combine a format with a film stock?

Yes, and you should. The format sets the grain size, the depth of field and the shape. The stock sets the colour. Portra 400 on 4x5 and Portra 400 on 35mm are two different pictures.

Camera and format

The ways to size a frame, and the wording that gets each one.

The format is the size of the film frame or the sensor. It decides three things before anybody picks a lens: the size of the grain, the depth of field, and the shape of the picture. The same subject in the same light comes back differently on a 36mm frame and on a 4 inch by 5 inch sheet. This page covers the three sizes that most photographs are made on. It also covers two formats that give up frame area, and three cheap cameras whose faults became a look.

Frame size

Three sizes, from the smallest frame in common use to a sheet fifteen times its area. The larger the frame, the finer the grain and the shallower the depth of field at the same framing.

35mm format

The 36mm by 24mm frame: a 3:2 rectangle with grain you can see at any print size.

Medium format 6x6

A 56mm square on 120 roll film: six times the area of 35mm, and no long side.

Large format 4x5

A 4 inch by 5 inch sheet: fifteen times the area of 35mm, no visible grain, and a plane of focus that tilts.

Less frame

Two formats that give something up on purpose. One halves the frame to double the number of pictures. The other throws away the lens.

Half frame

Half of a 35mm frame: an 18mm by 24mm upright picture, 72 to a roll, with the grain twice the size.

Pinhole

No lens at all: everything equally soft, everything in focus, and an exposure measured in minutes.

Cheap cameras

Three cameras built to a price. Each one has a fault that people learned to ask for: a dark corner, a hard flash, or a computer that smooths skin.

Holga

A plastic 120 camera: dark corners, a sharpish centre, light leaks, and an exposure nobody controls.

Disposable camera

Fixed focus plastic, fast colour film, and a flash that fires nearly every time.

Phone photo

A tiny sensor behind a wide lens, and a computer that decides how the picture looks.

Shoot one of them

Copy a prompt into an image model and pay for that one run. No subscription.

Open an image model

Other look groups

Colour film stocksThe colour stocks, and what each does to skin, to sky and to green.12 colour stocks Black and white film stocksThe stocks, and what each one does to grain, to skin and to the sky.8 black and white stocks Slide and instant filmThe positive stocks, their narrow latitude, and the wording for each.8 slide and instant stocks Darkroom and processThe changes made to the film itself, and the wording for each one.6 darkroom processes Historical processesThe processes from before the film roll, and the wording for each.10 historical processes Photographic genresEach genre written as the lens, the light and the distance that make it.16 photographic genres Product and commercialThe shots a product needs, and the light, shadow and edge each takes.10 product shots

Cinematic techniquesShooting a video rather than a still? The same reference, for the camera in motion.

Start from the grain and the shape. 35mm gives visible grain and a 3:2 rectangle. Medium format 6x6 gives a square and almost no grain. Large format 4x5 gives no grain and a plane of focus you can tilt.