Kodachrome is famous for, among other things, being tricky to scan well. I've been scanning quite a lot of Kodachrome, shot during recent travels, so I figured I'd share what I've learned. Questions and comments about scanning Kodachrome are common on various photography forums, so I know it's something a lot of people struggle with. If you have some Kodachrome you need to scan, you might find this useful.
I'm scanning uncut, unmounted film with a Nikon Coolscan 5000, on a Mac. I have the lab send me the developed film uncut, then cut it myself into strips of six, because it's easier to work with than feeding the scanner one mounted slide at a time. I can tell it to scan all six frames on a strip and then go do something else while it's working.
Also, I sometimes remove a partially-shot roll from the camera, and when reloading and advancing it, it's rarely going to line up perfectly, and I fear this might confuse the cutting process at the lab.
The downside of not having the slides mounted is that, if a frame is the first or last on a strip, it can sometimes not sit perfectly flat in the scanner. This results in blurring at the edge of the frame. Should it become a problem, I can always mount a slide myself.
Software: Nikon Scan
The Nikon Scan software isn't too bad; the user interface, while not very good, can be conquered, and it produces decent scans without too much effort. It is, however, a PowerPC-only application, and since Nikon is discontinuing all of its film scanners, it is unlikely ever to be updated again. I'm running it on a G5, but once you go all-Intel, it'll have to run under Rosetta.
The real problem with Nikon Scan arose when I started trying to scan in volume: it crashes a lot. I put in a strip of film, get previews, crop and tweak, and then tell it to do the scans, which will take a while. But Nikon Scan can rarely make it through a strip of Kodachrome without crashing, so I can't just leave it unattended. Each time it crashes I have to figure out which frames it has successfully scanned – and it doesn't do them in order – and then start over from scratch, previewing and cropping the others, and see how many more it can get through before crashing again. This gets old very quickly, and again, this software is unlikely ever to be updated. (These crashes don't seem to happen when batch-scanning black-and-white negatives.)
As with their cameras, Nikon makes decent hardware, but they are not a software company and really need to stop pretending to be.
On the plus side, Nikon Scan has Digital ICE for infrared dust and scratch cleanup, and the exposure adjustments are easy and presented in photographer-friendly EV units. There is a dedicated Kodachrome setting to help with the unique properties of this film.
Software: VueScan
An alternative to using the included software is VueScan, which works with many different scanners, and is under active development, unlike Nikon Scan.
VueScan's user interface is pretty bad. It needs to be learned, with all its quirks, and some visits to the user manual will be necessary. But once you figure it out, it works very well. It supports multi-pass scanning (like Nikon Scan) and infrared cleaning (not Digital ICE; more on this below), and unlike Nikon Scan, it can batch-scan strips of Kodachrome without crashing.
It also offers a nice feature that Nikon Scan lacks: a multiple-exposure mode. In this mode, two scans are done, one exposed normally, and one overexposed to get more shadow detail, and the two scans are combined. This can help pull out shadow detail when the dynamic range on the film exceeds what the scanner can get in one exposure.
There are more levers and buttons to tweak, and not all of them are self-explanatory. Once you find some settings you like, you can save an INI file containing those settings, and in theory, load this file up later to restore those settings. In practice, I have been unable to make this work: loading an INI file silently fails to actually change the settings to the saved values. Since so much of VueScan needs to be figured out, it's likely that I simply haven't figured out the correct incantation.
If someone could create a good user interface for this thing, it would be great. But since it doesn't crash, and since it has the multiple-exposure mode, this is now what I'm using most of the time. I have found a couple of images where Nikon Scan inexplicably gets me better color rendition, but on the whole, the scans from VueScan are at least as good and often better.
Software: Silverfast
Another software option that comes recommended by many is Silverfast. This comes in a bewildering array of versions, and the terrible website makes it difficult to know which one you should be looking at. Apparently this software includes a Kodachrome setting that tries to do a good job with this film.
Silverfast's pricing is ridiculous, as is their policy that your license is tied to a particular scanner, so that if you later buy a new scanner you need to buy the software all over again. I haven't tried Silverfast and don't intend to.
Resolution
Scanning at 4000dpi produces a 21 megapixel image file, and none of the data appears to be superfluous. However, this can in no way be compared to 21 megapixels from a digital camera. Film has grain, and the grain is an integral part of the “look”; grain is to film as pixels are to digital. But it takes more than one digital pixel to represent a piece of grain, so pixel size and grain size are not comparable in terms of useful resolution.
From shooting the same subject with the same lens (at a different zoom setting, to allow for the frame size difference) on Kodachrome and on my Nikon D2x, the Kodachrome, scanned at 4000dpi, seems to resolve slightly more real detail in the subject than the 12 megapixel D2x. But, the digital camera's image is much cleaner, owing to the lack of grain. Depending on how much the grain contributes to, or detracts from, the image, the digital image might be friendlier to extreme enlargement. The two just look different.
Of course, this is a digital camera that is several years old. Today's DSLRs offer higher resolution. Let's not be under any illusion that the 21 megapixels we're getting out of the scanner is the same as getting 21 megapixels from a digital camera. 35mm film is as good for landscapes with extreme enlargement as it ever has been, which is to say, not at all ideal. But people spend too much time looking at their pictures at 100% on the screen, which is like looking at a film shot through a high-powered microscope, and what you see there doesn't matter all that much for photography. You can make 16x24 or larger prints from these scans with no problem.
Contrast Range and Shadow Detail
Kodachrome is a high-contrast film, with detail deep into the shadows. It doesn't have as much dynamic range as negative film, but some images can have quite a lot, and it can be difficult to get a scan with all that shadow detail intact.
Using Nikon Scan, I set the analog gain so that the highlights are as far “to the right” as they can go on the histogram, and with many images this is enough. Some still lose the shadows. Nikon Scan includes a post-processing feature called “Digital DEE,” which boosts dark shadows. It's not bad, but it's entirely digital post-processing, which I'd rather not apply to my master scans.
VueScan allows gain adjustment, too, though the poor interface makes it quite a bit more difficult to deal with. The results are pretty much the same, but are easier to reach with Nikon Scan.
VueScan's multiple-exposure mode is usually a better bet. It can record detail well into the shadows, which can be later boosted in Lightroom or Photoshop as desired. In fact, the multiple-exposure mode works so well that I am simply leaving it enabled all the time. This is something Nikon Scan just doesn't have, and it's a big win for VueScan – though in practice only a small number of images actually need it.
Both programs offer curve adjustments, gamma adjustment, and the like, but this is strictly digital post-processing, best left for later. I don't use these adjustments at all. I can adjust the tone curve non-destructively in Lightroom later, and use Lightroom's “fill light” adjustment to bring up the shadows if necessary. This seems to work at least as well as the “Digital DEE” in Nikon Scan.
VueScan comes “out of the box” with a curve adjustment being applied by default. I changed this to be flat and left it there, and neutralized all the other adjustments.
Color Rendering
The goal is to get scans that look like the original film. Nikon Scan's colors were consistently slightly off for me; I loaded up a frame with known neutral colors and made some small adjustments to the analog red, green, and blue gain until neutral was neutral.
I did exactly the same with VueScan, which worked fine. However, VueScan also has a built-in database of film types, the idea being that, if you tell it what kind of film you're using, it knows the characteristics of the film and can work better.
However, this is problematic. If you set VueScan's “Media” setting to “Slide film,” which sounds like the right thing to use, then the software actually attempts to correct the colors to remove the film's unique look – the manual actually says that, with this setting and the film type set, it will attempt to make Kodachrome and Ektachrome scans look the same! I can't imagine why anyone would ever want this.
As it turns out, the actual correct “Media” setting is “Image,” which prevents any of this “film correction” from happening. Remember this if you use VueScan: “Slide film” is not what you ever want when scanning slide film. (I haven't yet tried scanning color negative film with VueScan, but I can't imagine it would be what you'd want for that, either. I could be wrong. Someone obviously thought this was a good idea, and that someone obviously doesn't shoot slide film. Why go to the trouble of choosing a film you like, only to have the scanning software try its best to defeat your choice?)
VueScan lets you run a calibration using an IT8 color target. I don't have one, so I don't know how well this works.
I haven't seen any point in the other color-correction options in either piece of software. This is just digital post-processing that is best left to Lightroom.
On some images, VueScan's colors come out far too cool, too blue, too green – way off, and no amount of adjusting in Lightroom can get them back. The same images scanned with Nikon Scan look fine. As it turns out, there is an obscure setting deep within VueScan's “Crop” settings, helpfully called “Buffer,” which instructs the software to ignore some part of the outside of the frame when calculating color balance, so that the black edges won't confuse it. I know, right? How could you possibly miss that? It defaults to zero, but setting it to 15% gets past the frame edges and makes everything much better.
Multi-sampling
With either Nikon Scan or Vuescan you have the option of using multi-scanning mode, where the scanner does multiple scans and averages them to reduce the effect of digital noise (noise in the scanning process, not on the film). This is separate from the multiple-exposure mode. In practice I haven't seen any benefit going beyond four samples. More samples means each frame takes longer to scan; two samples takes twice as long as one, three takes three times as long, and so on.
Digital ICE, or Infrared Cleaning
Some film scanners have a fourth, infrared, channel, in addition to the usual red, green, and blue. This is used for automatic cleaning of dust and scratches in the scans. The idea is that dust and scratches are opaque to infrared light, but the dyes in film pass infrared, allowing the software to figure out what needs to be fixed. This doesn't work at all with traditional black-and-white film, because the silver in the film also blocks infrared. And, the dyes in Kodachrome (unlike those in any other color film) transmit infrared differently, which causes a problem trying to use infrared cleaning with Kodachrome.
The usual mantra that you will see in a lot of places is that “Digital ICE doesn't work with Kodachrome.” Then you will find people trying to correct the record, saying that, “on the most recent scanners, Digital ICE does too work with Kodachrome.” My experience is that neither of these things is entirely correct.
“Digital ICE” is a trade-name, for one particular implementation: it is not a generic name for any infrared cleaning. Nikon Scan includes a licensed implementation of Digital ICE. On the Coolscan 5000 (and 9000), this is advertised as working on Kodachrome, with the caveat that some images may be negatively affected.
It works fairly well, a lot of the time. Sometimes, though, it leaves nasty artifacts; the main problem areas seem to be edges of dark objects on bright backgrounds. Also, when it does “fix” something, it can often leave behind some trace of its work that you still have to fix up later in Photoshop (or some other program). It seems to be okay to just leave it on when batch-scanning; if it fails on some images, the defects will usually be too small to see at web size, and if you want to use a particular image at larger sizes, you can re-scan just that frame with the ICE disabled. In practice, at least half of my images would need to be re-scanned if I want to enlarge them a lot, so my verdict is that Digital ICE “sort of” works with Kodachrome, but if you're going to be printing your images, you'll probably need to re-scan and manually clean them up like you would with black-and-white.
VueScan contains its own implementation of infrared cleaning (not Digital ICE) that works with any scanner that provides an infrared channel. On Kodachrome, again, the results are usually good enough for web size, but if you look more closely, the results aren't even as good as the Digital ICE in Nikon Scan. Almost all Kodachrome images have objectionable artifacts from VueScan's infrared cleaning. Some of these can be cleaned up in Photoshop, probably more easily than cleaning the dust spots manually, but most are unusable at larger than screen size.
The artifacts that infrared cleaning leaves behind on Kodachrome images range from the expected “soft areas” around places where it tried to fix something (usually easily fixed), to the artifacts around dark edges on bright backgrounds, to really bad “streaking” across some entire images. When batch-scanning I leave the infrared cleaning on, since most of the images won't be used except for on-screen viewing. Anything I want to print, though, will need to be individually re-scanned and manually cleaned up. If I'm scanning just one particular image that I know is a “keeper” I will turn the infrared cleaning off.
VueScan has a feature where you can have it highlight areas of the preview image that it has decided are defects that need to be cleaned up. Turning this on reveals why you're getting artifacts: with Kodachrome it often highlights large areas of the image, including those dark edges.
So, the routine I've settled on is to batch-scan in VueScan, with infrared cleaning and multiple-exposre enabled, setting white points on each preview but letting VueScan determine the exposure. If a particular image is great, I'll re-scan it without infrared cleaning, and possibly with manual exposure adjustment if the shadows are especially deep. In the rare case when I think Nikon Scan might do it better or more easily, I can run that.
If you're getting ready to scan some Kodachrome, I hope my experience is helpful to you.
Hi,
These instructions are great for me. I'm also scanning kodachrome with a Nikon Coolscan 5000 and Vuescan on a Mac. Some of my images are coming out unbearably and (with my semi-competence in Photoshop and Lightroom) irreparably blue, and I do see those artifacts from IR cleaning at the borders of bright and dark sections.
What do you mean by saying "I changed this to be flat" in regards to the default curve adjustment? That sounds like a good idea to me, but moving the curve sliders from their original positions at 0.25 and 0.75 respectively makes the image look crazy. I moved the blacks slider to 0.001 and the whites to 0.999, thinking I'd get the most information with these settings, but the images are horribly blue. The slides themselves look fine, though.
Thanks you for writing this all up!
Posted by: Jack | 07 October 2010 at 05:30 PM
If your curve defaults are 0.25 and 0.75, then the defaults have changed and this no longer applies. When I started doing this the default had a contrast curve applied.
For the blueness, make sure you're setting that "Buffer" setting. Mine were also coming out irreparably blue until I changed that.
Posted by: Jeremy | 07 October 2010 at 07:40 PM
Thanks for your insight into what is going on. I'm just embarking on scanning my slide collection, mostly Kodachrome. I have a Nikon 5000 plus a feeder because most of my slides are already mounted. And a tip for anyone buying one second hand - get it serviced and cleaned. The results justify the cost easily.
As you found, Nikon Scan is a little cumbersome to use, and I have mostly used Vuescan, despite its unfriendly interface. I am fortunate to have an old g5 iMac so I can still run Nikon Scan if I need to. But it is slow....
I was interested in your comment about the Buffer because some of my films come out very, very blue. Changing the buffer (default is 5%) makes no difference at all. But maybe this is because I am using Auto crop and there is therefore no buffer needed.
In fact I have not been able to get Vuescan to get rid of the blue at all. I ended up tweaking the blue and red Levels in Photoshop to get a pleasant, but perhaps not entirely accurate, result. The settings I used were blue 0.84 and red 1.41. I tried this with several frames from the same film and most were improved. Some of the darker ones - lots of shadow - ended up with a reddish glow, so not ideal for everything.
Nevertheless, my prime goal is to get the slides scanned so I can use the images. Given that I am likely to need only a small proportion of the thousands of images, I'm inclined to leave the raw scans as they are, and tweak them when I need them.
I have real doubts that any single combination of settings will work for everything. :-(
Posted by: David | 18 January 2012 at 07:12 AM
I found the blue to be irrepairable, so changing the Buffer setting was necessary. Try setting it even higher. Having said that, Vuescan has been through a lot of updates since I wrote this, and I haven't scanned any Kodachrome with it recently, so something may have changed. Don't just assume you can fix the blue later though. I found the Auto Crop to not work that well and always need adjustment.
The good news is that scanning color negative film turns out to be a lot easier. :) I miss the Kodachrome look, but I don't miss scanning it.
Posted by: Jeremy | 18 January 2012 at 10:42 AM