Scanning Kodachrome slides and Digital ICE

Kodachrome filmWhile ScanMyPhotos champions scanning of your photos to protect them from the unforeseen, we also feature professional 35mm slide scanning services. Each slide is individually hand-scanned by our experienced technicians, you can select to have each adjusted to achieve the optimum color and density, so you end up with the best possible scan at either 2,000 or 4,000 dpi. One issue arises when scanning Kodachrome slides and trying to use the Digital ICE process. It is a powerful scanning tool built into nearly all current slide scanners. However, Kodachrome tends to be tricky to scan. First, a little history, and then we will discuss the issues that everyone faces when scanning Kodachrome.

UPDATE: How to get digital copies from 35mm KODAK® slide carousels

Before reading this report. An update. professionally digitizes all your photos this fast.

While we have scanned six hundred million images, news stories like these made us so popular, but no order is more precious or important than yours. We are here to help. Sign up to receive free updates for loads of photo tips, news updates, and crazy-discounted deals.


What is Kodachrome?

Kodachrome is famous for, among other things, being the topic of a Paul Simon song, a U.S. State Park in Utah (Kodachrome Basin State Park), and being tricky to scan. The film itself was introduced by Kodak in 1935 but was discontinued in 2009, and nearly all film processing stopped in 2010. Since the film was discontinued, there was no reason for labs to continue processing the film since processing was complex and exacting, requiring technicians with extensive chemistry training and large machinery. Think of them as the Walter Whites of film processing.







So why was Kodachrome so popular if it was so difficult and expensive to process? There were several reasons, including the film’s long-term stability, which under suitable conditions were far superior to other types of color film, and having better details in the shadows and deeper, richer colors than different film types. To compare the film types in digital photography terms, Kodachrome contained approximately 20 megapixels of data in the 24 mm x 36 mm image. In contrast, other film had about 12 megapixels of data at a comparable ISO rating.

[Tweet “Retweeting this to thank @TechConnectify for all their smart tech tips”]

How can I tell if I have Kodachrome slides?

The easiest way to recognize Kodachrome slides, but the least reliable, is from the slide mount itself. Many labs that processed Kodachrome used special cardboard mounts that specifically say “Kodachrome” or “Kodachrome Transparency,” other labs used mounts where all printed text was printed red. The “red text” method is less reliable since it could have just been the lab’s only mounts for all slides they processed.

The most reliable way to tell can be the most challenging method until you get some practice. Kodachrome slides will have a slight base relief effect on the emulsion side, so the surface will not be perfectly smooth. No other type of slide has that same effect. What side is the emulsion side? If you are lucky, it is the side where the mount says, “This side towards the screen.” If it isn’t noted on the mount, check both sides and if you don’t see the effect on either side, you know it isn’t Kodachrome. It can be hard to pick up at first while you tilt the slide back and forth under some light because the slide has to “catch” the light just right to see the effect; however, once you can see it, it is easy to replicate with other slides. You can learn to tell without holding it up to a light with practice.

Side-by-side comparison of Kodachrome vs Ektachrome
Side-by-side comparison of Kodachrome vs Ektachrome. Note the “texture” on the Kodachrome slide. Click to enlarge.

KODAK DIGITAL ICE™ Technology works with slides and film formats (negatives) but not with photographic pictures. KODAK DIGITAL ICE cannot be used with photographs. However, we feature “Photo Soap” to enhance your images..

The Kodak software lets “dust bust” while we scan—improving overall efficiency and predictability within the postproduction workflow.

KODAK DIGITAL ICE Technology works from within the scanner to detect and reduce dust and surface scratches without softening, blurring, or altering the image. A tri-level defect matte is generated, depicting pixels that have been altered and defects that require additional attention. So, if a defect is found, that is greater than what can be corrected by the system.


How it Works:

  • Infrared channel detects density differences and defects on the film
  • A tri-level defect matte indicates the location and severity of the defects
  • Advanced pixel operation, utilizing Kodak algorithms, substantially reduces defects

Digital ICE and Kodachrome

“So, how does this affect my scans?” you may ask. Scanners have three channels, one for capturing red, one for green, and a third for blue. However, scanners that implement Digital ICE also have a fourth infrared channel. The long-wave infrared radiation easily passes through the film, but when it hits dust, scratches, and fingerprints, it does not pass through as easily. The internal workings of the scanner then piece together an image based on what the infrared channel found to “remove” the defects. The issue arises with Kodachrome and the unique, developing process that creates various film dyes. Kodachrome interacts with the scanner’s infrared channel in two ways. The absorption of the cyan dye in the film extends nearly into the infrared region, making this layer opaque to infrared radiation. Kodachrome film can also affect the infrared channel as it reflects the infrared light tricking the technology into thinking they are flaws.

These effects can sometimes cause a slight loss of sharpness in the scanned image when Digital ICE or a similar infrared channel dust removal function is used. In extreme cases, it can remove details altogether. I have seen it remove a person’s eyes in one instance, and in another, it entirely removed a small dog from a picture of it playing in the snow.


Some people will say that “Digital ICE doesn’t work at all with Kodachrome,” while others claim that new scanners can easily handle Kodachrome slides using Digital ICE. Our experience has been that neither is accurate, but the truth lies somewhere in the middle. It works much of the time just fine, but when it goes wrong, it produces completely unusable scans. Unfortunately, due to our proprietary scanners and software, we cannot simply turn Digital ICE on and off from scan to scan. We must have it on or off for an entire batch of scans. For this reason, when you purchase slide scanning from ScanMyPhotos, we have three options to choose from:

  • Scan all slides with Digital ICE on
  • Scan all slides with Digital ICE off
  • I will group my slides by type to be scanned with Digital ICE on and off accordingly.

Grouping your slides by type will produce the optimum results, but some prefer to have some chronology to their scans, or perhaps all of the slides are in a carousel mixed together which makes it hard to separate the types. In these cases, it is up to you. As noted, Digital ICE will work for many Kodachrome slides; however, there may be some here and there that produce poor results. If you have selected to have all of your slides scanned with Digital ICE on and you receive some “funky” results, we will rescan up to 15 slides per order for you at no charge with Digital ICE turned off. Simply contact our customer support team ( to discuss the rescanning process and mail the slides back to us for rescanning within 30 days of the completion of your order.

[Updated 6/18]

Want news updates, discounts, and promo codes to save at Click here for our free “Tales From The Photos We Scan” email shares.