Editing Medium format (section)

===120, 220 and 620 film===
{{main|120 film}}

[[Image:Pentaxshift.jpg|thumb|320px|Pentax 6×7 format [[Single-lens reflex camera|SLR]] camera with [[perspective control lens]]]]
All medium-format cameras mass-produced today (as of 2024) use the [[120 film]] format. Additionally, many are capable of using the 220 film format, effectively doubling the number of frames available with 120 film.  Medium-format roll film is still available from specialty shops and photographic laboratories, yet it is not as ubiquitous as 135 (35&nbsp;mm) film.

The 620 format was introduced by Kodak in 1931 as an alternative to 120. It was discontinued in 1995. The 620 format is essentially the same film on a thinner and narrower all-metal spool. While 620 film is required on a number of old Kodak Brownie cameras, many of these cameras can accommodate the slightly larger 120 rolls/spools. In other situations where the camera cannot accommodate a 120 spool, the 120 film can be rolled onto a 620 spool in a darkroom or [[changing bag]].[[File:50th Anniversary Hasselblad.jpg|alt=image of a medium format Hasselblad camera with the viewfinder open.|thumb|50th anniversary Hasselblad 500 CM classic camera kit]]This film is shot in a variety of [[aspect ratio (image)|aspect ratios]], which differ depending on the camera or frame insert used. The most common aspect ratios are 6×6&nbsp;cm (square/1:1) and 6×4.5&nbsp;cm (rectangular/4:3). Other frequently used aspect ratios are 6×7&nbsp;cm, 6×9&nbsp;cm, and 6×17&nbsp;cm [[panoramic]]. The 6×4.5&nbsp;cm format is usually referred to as "645", with many cameras that use this ratio bearing "645" in their product name. Cameras that can switch to different aspect ratios do so by either switching camera backs, by using a frame insert, or by use of special multi-format backs. All of these dimensions are nominal; actual dimensions are a bit different. For example, 6×7&nbsp;cm might give an image on film that is actually 56×70&nbsp;mm; this enlarges exactly to fill an 8×10 sheet of paper. Another feature of many medium-format models is the ability to use [[Polaroid Corporation|Polaroid]] instant film in an interchangeable back. Studio, commercial and architectural photographers value this system for its ability to verify the focus and exposure.