Notes on the ColorNeg Photoshop Plug-In, Version 1.02c 9/15/8
With version 1.02 we have made it easier to get started with ColorNeg. Those of you who really hate to read instructions, skip to "Installation" below. When you install the ColorNeg plug-in as instructed you will also install the Scantique plug-in, included in the ColorNeg download. ColorNeg and/or Scantique will provide as-you-go messages to help you get started. If you try ColorNeg first and are not happy with the results, starting with Scantique instead can help identify and solve the problem.
ColorPos, ColorNeg, and GamSat are now available in larger dialogs with larger preview images to better accommodate larger displays. See
http://www.c-f-systems.com/Plug-ins.html#DialogSize
ColorNeg 1.02 is an Adobe Photoshop plug-in that correctly converts scanned color negative film images to digital positive images. ColorNeg is distributed as a fully functional demo version on our web site (http://www.c-f-systems.com/Plug-ins.html). ColorNeg Version 1.02c has built-in data for over 230 types of film from Kodak, Fuji, Agfa, Konica, China Lucky, Rollei, and Ferrania as well as simple devices that can be used with legacy and problem films. For more critical work there is a comprehensive color balance system with CC (color compensation) filter readouts, familiar to many photographers.
ColorNeg 1.02 introduced a real breakthrough in the ease with which satisfactory results can be obtained from negatives of unknown type and other negatives with checkered histories. Click a gray area - preferably very light gray to nearly white - and slowly scroll the FilmData control. When the overall image looks best, you have a Film Type number for that negative. Version 1.02a introduces the ability to adjust color balance by directly scrolling CC (Color Compensation) values or even by typing in CC values. The CC concept is central to understanding three-primary color photography systems, which, after all, is what you are working with whether you use film or a digital camera. Your images may contain "millions of colors" but every single one of those millions of colors is a mixture of just red, green, and blue. See the Addendum Manual for a complete description of CC scrolling and entry and FilmData control.
The following explains the basics of using ColorNeg. The manual has more detail on these basics as well as a clickable Descriptive Table of Contents guiding the reader to full explanations of the many powerful features that are also available in ColorNeg including the ability to easily match a series of pictures taken under similar conditions.
After you have installed ColorNeg (described just below), there are four requirements for getting a good start:
1. A good, well-exposed and properly processed negative. You can often get acceptable results from problem negatives, but wait until you have a little experience.
2. A good 16-bit/channel linear scan. Easy to do with some scanners, very tricky to do with others. If you can't get ColorNeg to work satisfactorily with good negatives, this is almost certainly the reason. The Scantique plug-in can help you get started on this, so try running Scantique before ColorNeg if you have problems. Proper scans are the key to success, as Scanning the Negative, below, explains.
3. A good "gray" area in the image as a color reference. Although ColorNeg often makes a good first estimate of the color balance, an area of anything from a dark gray road through a middle gray sidewalk to the (known) white of clothing is more certain. Later on you will find that ColorNeg has several methods to aid in color balance of problem images.
4. Even if your results are satisfactory please look at the section Color Management and Setting Gamma C in the manual. This will get you on the right road to color management of your converted negatives.
Installation
Download the zip ColorNeg102.zip file. Put the ColorNeg.8bf and the Scantique.8bf files in the Photoshop filters folder, typically
C:\Program Files\Adobe\Photoshop x\Plug-Ins\Filters
where "Photoshop x" specifies the version of Photoshop. Once the ColorNeg.8bf and Scantique.8bf files have been placed in the folder, Photoshop will automatically configure for ColorNeg and Scantique the next time it is started.
Scanning the Negative
The negative can be scanned as a negative, but often more satisfactory results are gained by treating it as though it were a positive slide. A 16-bit linear scan is **REQUIRED** in either case. What you want to end up with in Photoshop is a negative image which may have the same color cast as the negative (usually orange) and may be quite dark. With some scanners (Minolta, for example) getting a 16-bit/channel linear scan is simply a matter of checking obvious preference boxes but with some scanners this can be difficult. In particular a "linear" scan often can be obtained only by changing a "gamma" value from 2.2 to 1.0. If you have difficulty or are not sure you are getting a proper scan, please look at the scanner page on our web site
http://www.c-f-systems.com/Scanners.html
which has detailed instruction of how to obtain 16-bit/channel linear scans from several different scanners and scanner software systems. These instructions were contributed by NegPos and ColorNeg users. Even if your scanner software is not listed, comparing these case studies with what you are experiencing may give a clue that bridges the gap. We welcome contributions to the scanner page, which we will add with or without attribution, as requested.
Scantique can convert "standard" 16-bit positive scans (as you would use for a slide transparency, except at 16-bits/channel or maximum bit depth) to the 16-bit linear scan required by ColorNeg. We recommend this ONLY if you find it impossible to directly obtain a linear 16-bit/channel scan. How well it works depends greatly on whether and how the "standard" scan tweaks the positive scan data, trying to "improve" your results.
Starting ColorNeg
From the Photoshop Filter menu: Filter->C F Systems->ColorNeg. The C F Systems entry should be near the bottom of the Filter menu. There will be a short delay and the ColorNeg dialog will appear.
First select the maker of your film from the narrower pull-up list at the bottom of the dialog and then select the type of film from the pull-up at bottom left. At this point the image should be nearly correct - you may even find it satisfactory as is. If not, use the ScrollBar. To the right of the scrollbar is a checklist of Scrollbar options. "Lightness" should already be checked. Use the scrollbar to set the approximate lightness you desire for the image. If the color balance needs to be adjusted, find a patch in the preview image that should be gray (colorless) and click on it. "Gray" can be anywhere from quite dark to white. If possible, click several gray patches and see what happens to the image, choosing the best result.
With a good, correctly exposed, properly processed negative of identified film type, that is all that is required for satisfactory results with most images. However, ColorNeg has many features designed to give you a high degree of control over the appearance and quality of your color negative images while retaining the color integrity of the image. For instance, there are images which do not have well-defined gray patches in them, so the Auto Color and Color Adjust ScrollBar options, described the manual, take care of them and provide for more critical color balance in general. The remainder of this manual explains ColorNeg features and how to use them. We recommend using the clickable Descriptive Table of Contents as an easy way to understand what ColorNeg does and to locate what you need.
Demo Version
ColorNeg is distributed as a demo version our web site
(http://www.c-f-systems.com/Plug-ins.html). The demo version of ColorNeg embeds a gridwork in the images it produces. In general, this gridwork is not obtrusive enough to prevent evaluating the results and in fact we expect that some less critical users may find the results usable as is. To unlock the demo version and eliminate the gridwork, a key code may be purchased via our web site:
http://www.c-f-systems.com/Plug-ins.html
where you will find a paragraph starting in larger type:
"Purchase ColorNeg, ColorPos, and GamSat for PC."
Clicking this will take you to a secure site where you can purchase a "ColorNeg Family for PC" key code. As of 8/22/7 we started delivering a new type of key code. Our policy allows one key code to be used on up to three (3) computers belonging to the same individual or business and this SAME key code will unlock ColorPos and GamSat, not just ColorNeg.
ColorPos, ColorNeg, and GamSat are also available in versions for the Macintosh.