Dealing with historic or badly processed negatives in ColorPerfect's ColorNeg mode

The various film types included in ColorPerfect's ColorNeg mode or in the original ColorNeg plug-in cover a large number of color negative films that have been available on the market in recent years. All of these film types are intended for negatives that have been developed according to standard conditions. Since version 1.02 the original ColorNeg plug-in featured a completely revised FilmData slider. This tool was a breakthrough for characterizing negatives from other sources. Such sources may be negatives on older types of film, negatives on altogether unknown material or the occasional roll of film that has either been developed under special conditions for a certain reason or for which something went inexplicably wrong during processing.

In ColorPerfect the FilmData slider has been improved further and has become the FilmType/SubType/FilmGamma calibration system. This system is similar but not identical to the original FilmData slider discussed in parts of this page. The first two example negative conversions shown have been made with ColorNeg but images of the same or even superior image quality could also have been made with ColorPerfect. The same principles apply so we left these original sections of this page largely unchanged.

An extreme example from the early 1970s processed with ColorNeg

The following example illustrates the possibilities as well as the boundaries of working with such material in ColorNeg using a rather extreme negative. Below this paragraph you see a linear scan of a negative from the early 1970s. At the time fast negative films had a nominal speed of ASA 64 and negatives on such material tended to be thin and hard to work with. One option to work with an at the time extraordinarily high speed of ASA 400 instead was to underexpose the slide film Kodak High-Speed Ektachrome about 1.5 exposure values and to cross process the film afterwards to produce negatives. The example shown below is an available light shot of a scene lit by incandescent lights. Kodak High-Speed Ektachrome was intended for daylight and since it is a slide film it does not show the otherwise common orange mask.

As we have shown for negatives on current film types Photoshop's Image > Adjust > Invert command is not suited to convert color negatives at all. An attempted negative conversion using this route will retain extreme color distortions even after the resulting overall color cast has been removed so that there is pure white in the image. These color problems are due to wrong calculations in Invert and can't be corrected once they are in place.

With ColorNeg it is possible to convert even such extreme negatives into positives of acceptable quality. Of course modern films would yield a higher image quality by comparison. Nevertheless please note the detailed reproduction of color in the resulting image and the absence of any color cast. ColorNeg utilizes the full detail stored within the negative. Due to the high control in ColorNeg and the further image editing options in Photoshop the resulting image will outperform any traditional color print made from the same negative.

 

Instructions for working with the FilmData slider in the original ColorNeg plug-in

To characterize a given negative of an unknown film type please select the FilmData slider. Then click on any gray area in the image. In most cases light grays will give the best results when working with the FilmData slider. In the example one of the dancers wears a gray costume that can be used as a reference. Another option that works well in the example is using the white shirts of the men in the chorus instead.

The initial color balancing by click is a requirement. Afterwards use the slider to find the position that will yield the most natural color in all areas of the image. Be sure to hover over the full range of the slider at least once as the optimum in color can appear anywhere on the entire slider. For this example the optimum was located around film type 350. As soon as you are convinced that you have found the best setting for your negative you may test it by clicking on several gray spots in the image which differ in lightness. There should no longer occur any large color shifts. Smaller color shifts are to be expected though as the areas clicked upon are unlikely to be precisely neutral. Most will have some minimal amount of one color or another.

The film type number displayed after characterizing one negative of a series can be tried on subsequent negatives of the same film to establish whether a good characterization has been found. If so the film type number can be written down and used on other negatives on the same type of film that have been processed in the same way. In addition to this the user film list will be selected on activation of the FilmData function. You can also always save your settings there under the current or a new name as shown in ColorNeg's manual. After characterizing the material you should check whether the highlight setting needs to be adjusted.

Another example: A 1974 test negative on Kodak Ektacolor S processed with ColorNeg

 

Due to the positive feedback we received about this example page I have decided to add another case for you to look at. If you would like to do so please click here first to preload the image files used for this second example. Since many of you might not yet be familiar with ColorNeg itself I will also briefly hint at some important details not specifically related to the FilmData slider.

To the right you see a linear scan of a 35 year old test negative. Such a linear scan almost always looks very dark in Photoshop and that is absolutely fine as it contains all detail captured during scanning nonetheless. ColorNeg will handle encoding the result to the required tone reproduction curve for your chosen color space after you specify that Gamma C. To learn how to create linear scans with your scanner hardware visit our extensive scanning tutorials. The kind of linear data shown is what your scanner reads and its being so dark is merely a matter of interpretation of the data by Photoshop.

Let's look at another version of the same negative that has been gamma encoded and color balanced to illustrate that all the detail needed is in the linear scan. Creating such an image is neither required nor permissible when processing negatives with ColorNeg. All of that is done automatically. ColorPerfect's ColorNeg mode does allow working with gamma encoded scans but you should only use that feature if there is no other way for your scanner. Where that applies is documented in the scanning tutorials. Using advanced hardware features we could also use the lighting or exposure controls on some scanner models to remove the orange mask during scanning. The resulting linear scan will be processed by ColorNeg equally well as the still orange masked one shown first. Only if you use certain older scanners such unmasked input will perform noticeably better.

To get started let's again look at what Photoshop's Image > Adjust > Invert command would do even to the well prepared negative we looked at between the two linear scans. As expected the image produced this way with Photoshop alone will retain the large uncorrectable color distortions we saw before.

There is no data for the negative's film Ektacolor S built into ColorNeg and we have to use the FilmData slider again as detailed above to characterize our image. The film type I found here is not included in ColorNeg because a single image like the one at hand simply is not representative. We can't assess that this film type determined with the FilmData slider will yield good results for a majority of images on the same film without looking at more negatives on the same material. Still we are able to quickly find a characterization that seems to suit the single negative at hand.

ColorNeg allows different regions of a negative to be treated differently during the inversion by making use of a feathered selection set up in Photoshop by the way. We could for example use that advanced technique to make the detail of the fur stand out a bit more by adjusting the fur's lightness separate from the rest of the image.

Every now and then I get asked about the color of an example - especially about the skin tones' color. It is almost impossible to get precisely the same color rendition one gets in Photoshop to show on a web page. If you find that the image still has a color cast be assured that ColorNeg's color compensation (CC) filter system is perfectly suited to get any color balance you feel is right.

If you started out with a linear scan and have characterized the film type suitably any color casts in such an image will be manageable. To illustrate that let me show you six more versions of the final image we looked at. Each has been adjusted by a CC filter of a strength of 2 from the final image. The result is a subtle but visible change in color balance. In ColorNeg you can apply CC adjustments as subtle as +/- 0.1.

These are the CC adjusted images: Click on the following links to make our final image more Red, more Cyan, more Green, more Magenta, more Blue or more Yellow. These adjustments can also be thought of in the reversed terms of less Cyan, less Red, less Magenta, less Green, less Yellow and less Blue which is easier for many of us when trying to remove color casts. In ColorNeg you can therefore simply enter relative CC adjustments for all six primaries with -2Y and +2B having the same effect. Please always use our final image as a reference since all color changes denoted here are relative to that version of the positive image. In ColorNeg any combination of CC filters can be used and you will soon find the ideal filter pack.

A third example: A 1981 color negative on ORWO Color negative film from the GDR

Only recently I was given a box of old monochrome negative films from one side of the family. There also were around fifty color slides in that box among which I found a handful of color negatives in orange slide mounts. We could date one of those negatives precisely to 1981 because of the event depicted.

About 30 years ago doesn't seem to be such a long time for a color photo. The photo we are going to look at however was taken in the German Democratic Republic (East Germany) where monochrome imaging was predominant in the amateur market much longer than it was in Western Europe. That fact makes this the earliest color negative image from that part of the family I am aware of. None of the film types built into ColorPerfect fit this negative so I figured it might make an interesting addition to this page. Please click here first to preload the image files used for this third example.

Below is a linear scan of the negative. The orange mask has mostly been removed by use of suitable analog gain settings during scanning. Although we have already seen that this is fruitless let's completely remove the orange mask, gamma encode the linear scan and let's try to convert it using Photoshop's invert command. As expected that doesn't work. ColorPerfect can be used to create a superior inversion of the negative and to process that into a pleasing positive image.

 

After trying a couple of the built in film characterizations in ColorPerfect's ColorNeg mode we notice that none of them work for the negative at hand. What indicates that is the fact that color balancing by gray click on the white blouse fails. Clicking on a darker portion of that blouse will result in a large color shift accompanied by noticeable changes in luminance. Effects like that are typical for an ill characterization of the input.

ColorPerfect's FilmType slider can be used to find a reasonable characterization for negatives like this one. To do so we gray click a medium bright portion of the blouse or maybe the surface of the road outside of the garden. Then we run the FilmType slider through its entire range once. We are looking for the setting that produces an image with the most natural appearance. After identifying what seems to be the best point we switch to SubType mode and fine tune our characterization. It can be helpful to temporarily set the saturation control to a higher value while doing this as this will emphasize the changes in color. Switching back and forth between FilmType and SubType modes to further tune the characterization is recommended. Resetting the saturation control to 100 we have a positive image to start working on.

We could invert the negative in a manner that preserves the entire detail in the highlights of the white blouse. The overall appearance of the image is too dark for a sunlit scene however. The details of why that is are described in our article on preserving highlights in negative conversions. To remedy that we can remove some more black from our image. Some portions of the highlights would blow which we can countermand by turning ColorPerfect's highlight compression on to a degree that suits our needs. Next we can remove some white from the image which can also be thought of as removing fog or haze from a scene. As we don't want blotted out shadows we'll also turn on shadow compression in the process. As final steps we can apply a minor zone curve in ColorPerfect and set the saturation level to a degree that fits our wishes. Comparing the basic inversion we started with to this final image produced with the various adjustments ColorPerfect provides also is a nice demonstration of what ColorPerfect allows you to do when working on positive images that have color integrity.

If you don't agree with the final image presented here you could easily have made different choices in editing the initial positive image leading to an image more to your preference. Also note that this example was created as a first try on an unknown film type. It is very likely that the characterization determined could be improved while working with further images on the same type of film. If you found this page informative I'd appreciate it if you'd use the interactive features of this web page which are located directly above the main text to tell your friends and fellow photographers about it.