How to Identify Slide & Negative types for scanning

Memories 2 Digital • October 4, 2019

Negative Scanning Slide Scanning

There's a good chance you've come across the standard 35mm format slides & negatives, but there are many other less common types that can be harder to identify. We've compiled this guide covering the less common and rare slide & negative formats to help you quickly identify your slide type.

Mounted Slides

35mm Slide

By far the most common slide format, 35mm slides are generally encased in a paper of plastic holder. The transparency film size (section containing the picture) of 35mm x 24mm, with a viewable area of roughly 34mm x 23mm. There's also a rare smaller mount in addition to the standard 2" x 2" mount.

35mm Half Frame Slide

Half frame slides are half the size of a standard 35mm slide, and were popular as they allowed twice as many exposures per film roll. They produce a transparency film size of 18mm x 24mm, with a viewable area of 17mm x 24mm, though it can vary depending on the slide manufacturer.

126 Instamatic Slide

These slides are probably the most popular square format, introduced in the mid 1960s. They produce a transparency film size of 28mm x 28mm, with a viewable area of roughly 16.5mm x 16.5mm. It's worth noting that you'll need to crop further to 16mm x 16mm to avoid rounded corners with most 126 slides when scanning.

127 Slide & 127 "Superslide" Slide

This format was common in the early 50s, but lost out to the more popular 126 & 35mm formats later on. It was commonly sold in gift/tourist shops as a postcard style slide, due to large viewable area.

The standard 127 slide has a transparency film size of 40mm x 40mm, with a viewable area of roughly 39mm x 39mm. The "Superslide" variant produces a transparency film size of 46mm x 46mm, with a viewable area of 45mm x 45mm.

110 Instamatic Slide

The 110 format was a miniaturised version of Kodak's earlier 126 format, and was generally used in entry level and lower end camera. The small size of the negative (and resulting slide) makes enlarging difficulty. It has a transparency film size of 13mm x 17mm.

It's worth noting that these slides were produced in both the standard 2" x 2", as well as a small 1" x 1" mount. If you are planning on scanning the smaller variety, consider placing them in adapters as most scanning services will only scan the standard size mounts.

Film / Negatives

There's many different varieties of negatives, but similarly to slides 35mm is by far the most common. For older negatives, they might be as large as a full sheet of A4/Letter paper, and can be as small as 10mm x 10mm. The negative images are the master images, from which all other copies will be made. They must be treated with care and handled with caution, as the oil from your fingers, dust and light abrasions can permanently damage them.

When the film is developed it is a long continuous strip of negative images. During processing, it's generally cut into smaller strips of for easier packaging and handling.

It's often difficult to find places that still process film today, as there's only a small community of photographers still using film.

35mm Film

By far the most common format, still developed and produced today. It's usually well by scanners and produces high quality prints & enlargements providing the negatives have been cared for well. Each negative is sized 24mm x 36mm.

35mm Half Frame Film

This style of film was popular as it allowed twice as many exposures as the normal full size 35mm exposure. It's worth nothing that lower end scanners will often incorrectly recognise half frame exposures, so make sure your scanner or scanning service supports the format. The negative is exactly half the size of the standard 35mm at 24mm x 18mm.

126 Film

Introduced in the 1960s, this film was popular due to its use in Kodak's Instamatic series of lower end cameras. It produces a negative size of 28mm x 28mm.

110mm Film

This film was used on lower end cameras, and generally doesn't produce great enlargements. It's also worth noting that many scanning services can't scan this format as it's too small to fit into so scanners. 110 negatives are 13mm x 17mm.

Disk Film

This film format was introduced by Kodak in 1982, and never gained widespread popularity due to the tiny 10mm x 8mm negative size, which produced grainy, low quality images.

Unlike most other films, disk film was contained in a flat plastic cartridge roughly 8cm x 8cm in size. Each cartridge held held 15 exposures, and the disk was rotated 24 degrees between each exposure.

The small size of the film, combined with the non-standard shape means that it's very difficult to scan, so make sure to check that your scanner or scanning service supports the format.

120 Film, 220 Film (Medium Format Negatives)

Medium format encompases a range of frame sizes, including:

  • 6cm ×4.5cm
  • 6cm × 6cm
  • 6cm × 7cm
  • 6cm × 8cm
  • 6cm × 9cm

The most common format is 6cm x 6cm, which has a negative size of 56mm x 56mm. It's usually easy to identify medium format negatives due to their height of 6cm (around 2.5 inches). These negatives produce extremely high quality scans, but can't be scanned by lower end scanners.

Large Format Negatives

These negatives are usually for very early cameras, but were also used later on by professionals due to the increased detail available with the huge exposure.

Any negative larger than 4" x 5" (10.1cm x 12.7cm) is considered a large format.

Scanning Slides & Negatives

It's generally best to get slides and negatives scanned by a professional scanning service, as it's difficult and time-consuming to scan them at home. Most scanning services will have high-quality scanners that can batch scan at high resolutions, as well as using technologies such as DIGITAL ICE to automatically correct scratches and blemishes.

However you chose to scan you slides & negatives, make sure to exercise extreme caution when handling. The oil from your fingers, dust and other contaminants in the air can damage the exposures permanently.

Check out our guide on the best resolutions to scan at so you can get the best quality from you precious memories.