Film Scanners: General Information on Scanning Negatives and Slides

Using a special film scanner or a compatible flatbed scanner, it is relatively easy to digitize photographic film (negatives and slides). In this article, the procedure with such a device is roughly demonstrated and there are some tips for better results.

Some materials on the topic of film scanning

The easiest way to digitize photographic film is with a special film scanner: these devices have a “slot” into which a film holder with a film strip inserted is pushed. There are also universal models with a glass surface and cover. However, the basic scanning process is the same for all of these devices:

1. The negative/slide is scanned internally.
2. Using a high-resolution lens, it is electronically scanned step by step.
3. The scanner software then generates an image that appears “logical”.

Pure Film Scanners

There are scanners on the market that are only suitable for scanning photographic film. They cannot be used to digitize paper or similar materials:

Such devices can be quite compact or “desk-friendly”. If only 35mm film is to be digitized, they are also affordable.

These compact types of scanners are only suitable for negatives or framed slides. They also do not work unattended, but you have to insert a new film strip bit by bit or even move it frame by frame by hand. In addition, their price increases significantly if the larger medium format films are also to be digitized.

If you only want to scan a few 35mm films on a regular basis, a device like the shown ›Plustek OpticFilm 8200‹ would be the ideal solution, as it is compact and reasonably priced.

Comparison 35mm film / medium format roll film

If you only use the most widespread 35mm film or want to digitize a larger stock of it, you are in luck: the scanners for this are cheaper. If you want to scan larger formats, you will unfortunately have to spend quite a lot of money on a compatible film scanner. If you want to scan large format sheet films or special films, you won’t get anywhere with a device with a ‘slot’ for the film feeder.

Flatbed Scanner with Transparency Unit

For larger film formats, however, a film-compatible flatbed scanner with an integrated lamp in the lid is suitable:

There are flatbed scanners that can not only digitize overhead originals (paper), but are also suitable for scanning photographic film thanks to the transparency unit.

The “transparency unit” refers to the additional, movable lighting unit at the top of this device. Normal “office scanners” ^x only have a lamp underneath and a closed lid without additional electronics.

^xThese commercially available scanners are not suitable for digitizing films. Their resolution is also far too low for tiny originals.

With a suitable flatbed scanner, several film strips can be inserted at the same time. Appropriate film holders are available for this purpose:

Such a loaded film holder is then inserted into the scanner and the flap closed. Before doing this, you should make sure that the film strips are free of dust. However, good scanners also offer ‘infrared dust and scratch removal’ (see below).

Such a flatbed scanner is usually larger than a pure film scanner.

There are some of these devices from the manufacturer “Epson” in particular, with which you can also scan films and which are quite popular. Well-known (and usable) devices are:

• Epson Perfection V800 / V850 Pro
• Epson Perfection V700 / V750 Pro
• Epson Perfection 4990 Photo

The “Perfection 850 Pro” is the current model on the market. The other devices are either available as remaining stock or can be purchased on the second-hand market.

Tip: The old “Epson Perfection 4990 Photo” is roughly in the same quality league as the newer models – but is likely to be significantly cheaper on the second-hand market.

Such a flatbed scanner has two advantages over ‘real’ film scanners:

• You can scan many images at once unattended.
• You can also digitize larger film formats (including sheet film).

Where there is light, there is also shadow – There may also be disadvantages:

• Universal film holders often cause insufficient flatness or inadequate sharpness. This reduces the possible resolution.
• Flatbed scanners often have lower resolution optics or electronics than film scanners.

I myself worked with such an “Epson V750” for many years and was able to produce very high-quality digitized images. However, I had to modify the film holders somewhat and operate the scanner software as manually as possible. You can see here a 100% 35mm scan from such a scanner (Epson V800). Hint: open in new tab / window.

There are different holders for different film formats. The picture shows one for 35mm slides: you can insert several at once and these are then scanned unattended.

You can also place films directly on the glass surface or make your own holders (e.g. glass holders for perfect flatness) ^x.

^xHowever, it is important to ensure that the film is within a specific focus point, which must be tested.

… especially if you want to use them to digitize larger formats than 35mm.

With good film scanners, such a high resolution and sharpness is possible when digitizing film (here from a 35mm colour negative).

Scanner with optional transmitted light Attachment

Some special Scanners came onto the market in the 1990s and were apparently still being sold until the early 2010s: These types had an optional attachable accessory: a “transmitted light attachment”.

With this device, the lid is folded up and an additional box with an integrated, upper illuminated surface is positioned on the glass surface.

This was also the time when digital photography was just becoming popular and many people apparently wanted to get rid of their old film archives. I had tried out two of these scanners with an attachable transmitted light attachment: The scan quality achievable with them was pretty lousy.

The images scanned with these scanners can perhaps be used for showing on the Internet. In my opinion, such devices do not meet a slightly higher quality standard: they are technically slightly better office scanners for documents with the small, optional additional option of film transmission.

Pseudo Scanner

There are handy and very inexpensive little boxes on the market which are marketed as “film scanners” – but are technically not scanners at all. These devices are simple digital cameras with a macro lens in a compact, closed housing:

These small devices are often offered at particularly low prices. The image results are sometimes even acceptable – but not high quality.

Sometimes these “pseudo-scanners” even have a small display and an SD card slot, which means that a computer is no longer necessary for “scanning”. These devices are sufficient for viewing old recordings on a larger television set. They are not suitable for high-quality, larger prints. The software on my test device also had major problems converting color negatives into “logical” positives: there were always serious color casts.

Resolution & Dynamic Range

With film scanners, there are two specific values that can be used to theoretically estimate the expected quality of the digitized material:

• Resolution
  Are even tiny details digitized?
• Dynamic range (Dmax)
  Are details in very dense areas also captured?

The higher the resolution, the more minute details will be visible or distinguishable in a 100% view of the subsequent digital image file. The “bottleneck” is of course the film itself – it must be able to deliver these details.

If a scanner offers a real resolution of 3200 DPI – as a point of reference – this is a good value and can also be used for 35mm. However, if the films sag in the film holder or are not correctly positioned in the exact focus point, even a theoretically high resolution is useless. This is a typical weakness of flatbed scanners.

Dynamic range (Dmax) refers to the ability of a scanner to “look” as deeply as possible into the film layer. Slides are often very rich in contrast. Or some negatives are heavily overexposed. These film originals therefore have a particularly large contrast range: both almost transparent areas and very dense areas. The scanner should be able to read both with drawing.

Inexpensive scanners certainly always have a very low Dmax. A good, usable value – as a point of reference – is a Dmax of 3.5.

Scan Software

Every scanner requires a specific program in order to be correctly controlled by the computer – the scanning software. For film scanners, this point is even more specific. Here, the software must also be able to convert the orange color negative films into colorful images with high saturation and no color cast.

Scanning color negative film in particular can sometimes be frustrating. Many scanning programs sometimes fail to automatically filter out the images correctly.

They also often appear overloaded.

There are several scanning programs on the market. You don’t have to use the manufacturer’s free software with every scanner. Perhaps you can achieve better results with a (compatible) alternative? ^x However, scanning slides and black and white negatives is usually relatively simple. You certainly don’t need any special software for this.

^xElaborated, fee-based scanning programs are often quite confusing, bursting with functions and a beginner does not even know what is meant by all this.

Automatic Dust and Scratch Removal

Many scanners, which are also suitable for digitizing “analogue” film, have a very interesting function: scratches, fingerprints or dust on the film can be marked internally and then retouched by the software. The scanner has an additional infrared lamp integrated for this purpose. This process works something like this:

1. A regular scan is made in neutral light.
2. A second scan is made with infrared light.
3. The scanning software compares both results and finds certain “things” in the “infrared scan” which therefore cannot be part of the subject.
4. These areas are marked internally and retouched – completely automatically.

This would be important for digitizing large, dirty archives. With manual retouching, this is taking ages and it’s no fun either.

There are various names for this technology. The most common is Digital ICE = “Digital Image Correction and Enhancement”. On some devices it is also called FARE.

The automatic retouching of scratches and dust is usually quite reliable and good. In my practice, however, there were also problem areas that were correctly marked by the additional infrared scan. However, they could not be satisfactorily retouched by the scanning software. These programs can’t work magic when, for example, a thick scratch runs right through a face. They do not feature artificial intelligence (yet).

This is because these films have a relatively high silver content: These particles reflect the infrared light or do not allow it to pass through. It is therefore not possible to detect mechanical faults. However, detection is possible with color films (slide or color negative). These films have a different structure to B/W films.

If you want Quality, you have to wait

Scanning films takes quite a long time with many devices. With all ‘features’ activated, it can take up to 5 minutes per image.

The following points influence the duration:

• How large is the original?
  Medium format, 35mm, …?
• What target resolution is defined in the scanning software?
• Is multiple scanning activated there (if available)?
  “Multi Exposure”, “ME” for short: Multiple scanning to increase the dynamic range (see above).
• Is an additional infrared scan activated there (if available)?
  For automatic detection, marking and retouching of dust and scratches (see above).

There are some ‘industrial scanners’ (e.g. ›Frontier‹ or ›Noritsu‹) that can digitize images much faster. Devices for home use are usually much slower. You should be aware of this. A much faster alternative to scanning would be to take photos with a digital camera. However, this has other disadvantages (no infrared channel, room must be darkened, complicated set-up, etc.).

Scanning with a professional film scanner: These devices work much faster. But who places one of these up at home?

This was a rough overview of what types of film scanners there are, what they can do and how to use them. There are many other interesting articles on the subject of digitizing on my website to deepen your knowledge if you are interested. At the moment, most of them are only available in German.