Darkroom Magazine's "How to Choose a Color Analyzer" and Buying Guide (1979)
The following unsigned article and table appeared in the December 1979 (Vol 1 No. 7) issue of the now-defunct Darkroom Magazine (pp. 28-35). Color analyzers disappeared with color darkrooms, but at one time they were hot stuff (as the prices attest).
Special Note: the Buying Guide includes analyzers from the February 1983 (Vol 5 No.2) issue of the same magazine. - JO
Any photographer involved with color printing can tell you that good color prints do not appear by magic. It takes time, patience, and a lot of hard-earned knowledge to make consistently good color prints, and as far as we know, no new darkroom "gadgets" have been invented to replace these human qualities. That doesn't mean, however, that some of the new hardware can't make life in your color darkroom a little easier. The color analyzer, for instance, is one piece of equipment which, if properly used, can take much of the guesswork out of color printing.
You may have heard that color analyzers are somewhat like a genie in a bottle: rub it the right way and out pops the Answer. Not so. Color analyzers are fairly complicated to use and require a thorough knowledge of color printing, so they're not a panacea for the wet-behind-the-ears beginner. And many models are also quite expensive. But don't get us wrong; we're not trying to scare you away. It's just that color analyzers aren't for everyone, so we suggest that you keep your own particular color printing needs in mind as you read what follows.
What Is It?
Simply stated, a color analyzer is an electronic device that can analyze the density and color balance of a color negative (or slide), and store the information to assist in future printing of similar negatives. Subsequent negatives will be "analyzed" on the basis of the information obtained from the initial negative or slide, which serves as a "norm."
All color analyzers contain three basic components: a probe, the small-aperture attachment you place on your easel to collect information about your negative or slide; an electronic memory and its associated circuitry (the brains of the analyzer), which remembers the information gathered by the probe; and a meter, which allows you to read this information. Beyond these basic similarities, however, color analyzers differ widely in features and design. That's hardly surprising when you consider that the analyzers listed in our guide range from $175 to $2,195.
Rating the Probes
The light detector is the heart of a color analyzer; it's what enables the probe to read the projected negative or slide. Modern-day analyzers use either a photomultiplier or a silicon ("blue" cell) light detector. Although the photomultiplier is considered to be somewhat more sensitive to changes in density than the silicon cell, both are so sensitive that the differences are negligible in actual use.
What is an important distinction, however, is whether those analyzers which use a photomultiplier place it in the body of the analyzer or in the actual probe unit itself. Placing the photomultiplier in the probe unit has one potential disadvantage aside from added bulk: the photomultiplier will be susceptible to shock damage if the probe is knocked or dropped. Photomultipliers that are placed in the analyzer body receive their information via a pliable, fiber-optics tube and work just as well as ones in the probe. Silicon light detectors, on the other hand, because they are solid-state electronic chips, are almost impervious to shock and do not affect the size of the probe.
All probes have small reading apertures which you place directly over the area of the projected image you wish to analyze. If your picture includes people, you should definitely analyze a flesh tone. Some analyzers offer just one aperture size, while others offer two or three. A 4mm size is about right for reading flesh tones; a smaller aperture could result in a misreading if centered over a freckle or other facial discoloration. Smaller apertures can be useful at times however, especially for. reading highlights. And larger apertures are helpful if you want to "average" adjacent areas.
Overall Readings Too
Besides allowing you to take a "spot" reading through a small aperture, most analyzer probes will let you take an integrated or overall reading. With this method, the light from the entire projected image is "scrambled" by a piece of white, translucent plastic placed underneath the enlarging lens and the "integrated" image is read for color balance. The requisite piece of plastic is either supplied with the analyzer or available as an inexpensive accessory.
Because integrated analyzer readings program a middle grey tone to the entire picture (i.e., all colors are "in balance" and no one color predominates), you should only use them with photographs that contain a balanced mixture of colors and no flesh tones. If one particular color dominates your images (say, for example, you're a nature photographer and your scenic shots always have lots of green or blue), your best bet by far is to take a spot reading for that particular color.
The light from your enlarger must fall into the probe aperture at a 90 degree angle for it to work properly. That means unless your flesh tone or other reading area is directly below the enlarger lens, the probe will have to be tipped to allow light to enter it properly. A cosine-correcting probe design eliminates this necessity, so probes with cosine correction can be placed down flat anywhere on your easel with no resultant reading error.
Circuits and Memories
We promised ourselves this wouldn't be a "how-to" article, but to understand the "memory" of a color analyzer you need to know a few basics. To analyze a color negative, you first must "program" your analyzer. This is done by taking a "standard" negative and printing it to your satisfaction without the use of an analyzer. If you don't have a "standard" negative, you can purchase one from Kodak; some analyzers have one included with the instruction book.
After you have manually determined the proper filtration, exposure time, and lens aperture for the standard negative, you program this information into the analyzer. Its job is to remember the program, and use it as a standard by which to judge the other negatives you print.
You program the analyzer by turning its control knobs, which are generally connected to an electrical device called a potentiometer. The typical color analyzer has four such knobs, one corresponding to each of the three color channefs (cyan, magenta, and yellow) and one knob for exposure (image brightness). On some analyzers the knob corresponding to each channel is color-coded for easy reference. When programming most analyzers, the control knobs are adjusted individually until the meter nulls, or centers at zero.
Because it's so critical that the readings be accurate, some analyzers provide more than one control knob for each channel, permitting coarse and fine ad-ustments. You should be aware, lowever, that some high-quality analyzers contain circuitry so sophistiv cated that one control knob per color is all you need for an accurate reading.
All analyzers work well when your print size ranges between 4x5 and 16x20, but with prints much smaller or larger the amount of light reaching the easel may fall outside the range of the meter. Some analyzers have alleviated this problem by providing a sensitivity adjustment mechanism, which allows you to position the analyzer's sensitivity range to match the light output of the enlarger. And on some analyzers, you can use this control to assure precise meter "nulling" with click-stop enlarging lenses.
Multiple Memory Options
It's a sad fact of life that any color analyzer must be reprogrammed for any variation in your shooting or processing methods. Different lighting, film types, or new brands of chemistry or paper are just some of the factors that will throw off your "program." If you want to have a variety of programs for all the different shooting and processing setups you use, you'll have to get an analyzer that provides interchangeable memory modules. You can set up a different program on each module, and insert them into the analyzer as needed. Most analyzers with this feature come with one module included, and additional modules range in price from $16 to $95.
Meter Matters
Your analyzer communicates with you through its meter. Meters register both color filtration, usually in color correction (CC) units, and exposure, either in seconds or an arbitrary unit scale. At the center of the filtration scale is the null, or "zero" point. Filtration markings are relative values only, so if you make a 5CC change in your acetate filter pack or turn your colorhead knob 5CC, it may not correspond to a 5CC change on your analyzer. Also, note that if you use acetate filters with your enlarger, it may be impossible to get the analyzer meter to null exactly, because the analyzer meter's increments may be smaller than the smallest filter unit. Some color analyzers also include an optical density scale on the meter face. You can use it to measure the contrast range of the negative, and it can be used for both color and black-and-white printing. It helps in establishing the exposure time for your initial program, as well as the paper grade that's best for your negative. If your probe is "cosine corrected" this scale can also predict the dodging and burning requirements of your print. But while the optical density scale is a handy reference, you should be aware that the filtration and exposure scales are capable of providing similar information when used properly.
Can You Read It?
Because the purpose of the meter is to provide you with data, its overall ; readability is important. Naturally, the larger the meter face, the easier it will be to read. You'll be reading the meter in the dark, so it will have to be illuminated. When examining a meter, check to make sure the extreme ends of the scale can be easily seen. Some analyzers have meter lamps which can be moved to light just the part of the meter needed, and some offer "variable brightness," allowing you to dim the light to guard against paper fogging. In general, back-lit illumination offers a soft yet easily visible light. And with meters using a digital readout system rather than a needle, the size of the numbers is more important than the size of the meter face.
As you've probably gathered by now, buying a color analyzer is not a simple task. They are complex instruments with many important variations in performance. Armed with these pages, however, you should not only be able to ask meaningful questions of your local photo dealer, but be able to understand the answers as well.
Name | Probe Type | Probe Aperture | Cosine Corrected | Control Knobs per Channel | Adjustable Sensitivity | Memory Modules | Optical Density Scale | Display Size | Readability |
Price | Comments |
---|---|---|---|---|---|---|---|---|---|---|---|
Beseler PM1A | Photomultiplier | 3.2mm | no | 1 | no | no | no | 2 in. | back-lit |
$175 | Photomultiplier in probe, meter nulls only, no linear readout |
Beseler PM2 | Photomultiplier | 3.2mm | no | 1 | no | no | no | 4-¼ in. | illuminated |
$400 | Photomultiplier in probe, mirrorband eliminates parallax, 3 switchable memory banks built-in |
Beseler PM2L | Photomultiplier | 3.2mm | no | 1 | no | no | no | 4-¼ in. | illuminated |
$270 | Photomultiplier in probe, mirrorband eliminates parallax |
Beseler PM2M | Photomultiplier | 3.2mm | yes | 2 | no | yes ($37.50) | yes | 5-¼ in. | illuminated |
$600 | Photomultiplier in analyzer, morrorband eliminates parallax, program verify switch |
Beseler PM3L | Photomultiplier | 3.2mm | no | 2 | no | yes ($37.50) | no | numbers ½ in. high | digital |
$450 | Photomultiplier in probe |
Beseler PM4L | Photomultiplier | 3.2mm | no | 2 | no | yes ($50) | no | numbers ½ in. high | digital |
$975 | Photomultiplier in chassis; fiberoptic cable; internally stabilized; program verify circuit. (1983) |
Colourtronic Fujimoto Color Analitimer | CdS | 6mm | n/a | 1 | no | no | no | n/a | 4 spot LEDs |
$250 | reads all 3 color channels simultaneously; probe is used at lensboard for integrated color analysis and on easel for spot exposure; built-in-timer, 1-60 seconds (1983) |
Cosar/Mornick 321 | Photomultiplier | 5, 11, 13mm | no | 2 | no | no | yes | 2-½ in. | back-lit |
$400 | Photomultiplier in probe, fiber-optic accessory probe $55 |
Cosar/Mornick 322 | Photomultiplier | 5, 11, 13mm | no | 1 | no | no | yes | 4-½ in. | back-llit |
$250 | Photomultiplier in probe, fiber-optic accessory probe $55 |
Cosar/Mornick 328 | Silicon | 5, 11, 13mm | yes | 3 | yes | yes ($49.95) | yes | 8 in. | electro-luminescent |
$745 | indicator lamps on chassis |
Eseco / Speedmaster SM 400 | Photomultiplier | 3mm | no | 1 | yes | no | no | 4 in. | illuminated |
$600 | Photomultiplier in chassis; fiberoptic cord (1983) |
Eseco / Speedmaster SM 500 | Photomultiplier | 3mm | yes | 2 | yes | no | no | 5-¼ in. | illuminated |
$675 | Photomultiplier in analyzer |
Eseco / Speedmaster SM 800 | Photomultiplier | 3mm | no | 1 | yes | no | no | numbers ½ in. high | digital |
$945 | Photomultiplier in analyzer, infinite program capability |
Eseco / Speedmaster SM 1100 | Photomultiplier | 3mm | yes | 1 | yes | yes ($95) | no | 7-½ in. | illuminated |
$1,275 | Photomultiplier in analyzer |
Eseco / Speedmaster SM 1400 | Photomultiplier | 3mm | no | 1 | yes | no | 8 | numbers 3/4 in. high | digital |
$1,775 | Photomultiplier in chassis, fiberoptic cord (1983) |
Eseco / Speedmaster A-12 | Photomultiplier | 4.8mm | yes | 1 | yes | yes ($95) | no | numbers ½ in. high | digital |
$2,195 | Photomultiplier in analyzer, variable slope compensature provides auto compensation for over-under exposed negatives |
Jobo Fototechnic Colorstar | Silicon | 4mm | no | 1 | yes | no | no | ½ in. | digital |
$800 | Simultaneous readout of all 3 colors; built-in timer; slide potentiometers (1983) |
Kearsarge 2000 Color Command | Photomultiplier | 3mm | yes | 3 | yes | yes ($525) | no | ½ in. | digital |
$2,300 | Photomultiplier in chassis; fiberoptic cable; built-in timer linked to neutral channel (1983) |
Lektra 7610 Memory | Photomultiplier | 1/8" and 7/16" | no | 3 | yes | no | yes | 5-½ in. | illuminated |
$1,200 | Photomultiplier in chassis; fiberoptic cord, three 4-channel memories plus aux white-light channel. (1983) |
Lektra PTM/11 | Photomultiplier | 2.3, 11.1mm | yes | 3 | yes | no | yes | 4-½ in. | illuminated |
$750 | Photomultiplier in probe |
Lektra PTM/66 | Photomultiplier | 2.3, 4.8, 6mm | yes | 1 | yes | no | yes | 4-½ in. | illuminated |
$2,150 | Photomultiplier in analyzer, simultaneous 3-color filter adjustment, digital readout of color settings |
Macbeth PA 905 | Photomultiplier | 3, 6mm | yes | 1 | yes | no | yes | 4-½ in. | illuminated |
$1,395 | Photomultiplier in analyzer, pilot lamp |
Minolta Color Analyzer II | Silicon | 4.5mm | no | 1 | no | 2 | no | n/a | twin-spot LEDs |
$276 | Compact one-piece unit; battery operated; LEDs are balanced to null (1983) |
Omega SCA 100 | Silicon | 5mm | yes | 1 | no | no | no | 2 in. | back-lit |
$200 | Compact 1-piece unit |
Omega SCA 300 | Silicon | 3, 5mm | yes | 1 | no | yes ($41.95) | no | numbers 5/16 in. high | digital |
$800 | Light detector uses 3 silicon cells, 8-foot probe cord for large prints |
Omega SCA 400 | Silicon | 3, 5mm | yes | n/a (comments) | no | yes (8) | no | numbers 5/16 in. high | digital |
$2,000 | Light detector uses 3 silicon cells, simultaneous 4-channel readout, built-in timer (1983) |
Philips PCA 060 | Silicon | comments | comments | 1 | yes | no | yes | 1-½ in. | illuminated |
$290 | Probe gives integrated reading for entire negative, cosine correction unnecessary |
Philips PCA 061 | Silicon | 25mm | n/a | 1 | no | no | no | 1-½ in. | illuminated |
$290 | Reads both additive and subtractive filtration (1983) |
Philips PCA 2060 | Silicon | 25mm | n/a | 1 | no | no | no | 1-½ in. | illuminated |
$340 | Reads both additive and subtractive filtration; cometically matches Philips Darkroom System 2000 (1983) |
Rodenstock CA-30 | Silicon | n/a | n/a | 1 | no | no | no | n/a | twin-spot LED |
$200 | Makes integrated readings at lens; LEDs are balanced to null (1983) |
Soligor Melico SM 20 | Photomultiplier | 3mm | no | 1 | no | no | yes | 2-7/8 in. | illuminated |
$200 | Photomultiplier in probe |
Soligor Melico SM 40 | Photomultiplier | 2mm | yes | 1 | yes | yes ($15.95) | no | 3-½ in. | back-lit |
$500 | Photomultiplier in analyzer |