Ollinger's Guide to Enlargers

Minolta Enlargers

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Quick Comparison

Model Era Format Baseboard Price (new) Notes
Color Enlarger 1975 6 x 7 cm 20 x 22"

Model I: $370
Model II: add $153
Model III: add $509

Reviewed in Modern Photography, Jan 1975
Color Enlarger II 1981 6 x 7 cm 19 x 21¼" tbd Reviewed in Darkroom Photography, Dec 1981 (Vol 3 #8)

Model Notes

Color Enlarger

Minolta Color Enlarger (1975)The following unsigned review appeared in the now-defunct Modern Photography magazine, January 1975, in the "Modern Tests" section. I've edited it slightly for brevity (though you'd never know it to read it below).

Specifications: Minolta Color Enlarger Model-I, diffused illumination, 80w, 18.5v. EKG or similar type halogen lamp, negative size from 16mm to 6x7, 39.4-in. calibrated upright, baseboard 20x22 in, color filter drawer 3x3 in, interchangeable light-mixing boxes for 35mm and 6x7 format, dichroic filter module. Model-II module converts basic Model-I to built-in color filter enlarger. Price: Model-I, $370; Model-II dichroic filter module, $153; Model-III (Model-I with dichroic filter module), $509; Color Analyzer, $296.

Up to now if you wanted an enlarger, you went out and bought one. If you wanted a color head, you added that to the machine you originally bought. If you then wanted a color analyzer, you could buy anyone's color analyzer for use with any enlarger. But the new Minolta Color Enlarger system has somewhat changed all that. It's based on a new idea whose time has come. In this enlarger. everything has been integrated into a single unified system with everything modularized, built-in and calculated to work together. In evaluating this system, there are a number of individual considerations. First of all, how good an enlarger (independent of the total system) has Minolta produced? What are the system's capabilities, advantages and problems in terms of what it was designed to accomplish? And finally, how good an alternative is it when compared to conventional, non-modular enlarging setups?

Let's look at the options. First of all, there's the Minolta Color Enlarger Model-I, basically a color unit only insofar as it has a filter drawer. Yet it can't be called a conventional B&W enlarger by any stretch of the imagination. By replacing the filter drawer module with a color head, it converts to the Minolta Color Enlarger Model-II. And by then adding the Minolta Color Analyzer, it becomes what is probably the most integrated (that has a double meaning, as we shall soon see) color printing machine available, short of highspeed industrial devices. Let's start with the basic Minolta Color Enlarger Model-I and then build up from there.

The enlarger sits on a 20-1/8" square baseboard. The upright measures 39.4" high and is a fairly massive 2-3/8 x 2-5/8" thick. The upright is finished in black, with white inch and centimeter calibrations on its face. It's fixed to the baseboard with four large Allen-head bolts. The vertical support arm rides on the upright guided by four roller bearings and counterbalanced by two spring units.

Loosen the raising-lowering control and the machine glides effortlessly on the upright. A twist of the wrist and it is firmly and immovably locked in place. Up to now we have a very well-made enlarger that combines good design with fine materials and engineering. But once we get to the enlarger head itself, everything changes. There's never been an enlarger head quite like it. The head is modular; that is, sections lift out and drop in so that the Minolta becomes a "whatever-you-want-it-to-be" enlarger. Loosen two screws at the top, lift a handle, and out comes the lamphouse itself. It contains a General Electric 18.5v 80w EKG lamp operated from a power supply which contains a stabilized transformer to convert line voltage to the required 18.5v.

The next module beneath the lamphouse is marked "Minolta Color Enlarger Mod-I." It serves two functions. It contains the filter drawer that takes 3" square acetates, and a tubular diffusion system. With a lightly-ground plastic disc at the upper end and an opal plastic disc at the lower end. This unique design concentrates the light beam before it enters the mixing boxes which are the lowest module.

Even something as simple as a filter drawer has been well-designed. For example, to install the filters, you open the drawer, lift a spring-loaded plate, drop the filters in and lower the plate which holds the filters flat. In that way. the filters can't expand during exposure and thereby prevent the drawer from opening. The lowest module is the light-mixing box. There are two types available, one for 35mm and one for 6x7. You can order the enlarger with either one. The mixing boxes serve to concentrate the light on the desired format, providing even illumination over the field. We'll talk about light intensity a bit later.

The focusing system is straightforward and well-made. A 2-¼" knob drives a heavy column through 5-½" of bellows extension. The action is smooth as silk and solid as a rock with no play or skew action throughout the focusing range.

The lens board is a 4" plate threaded to accept Leica-thread lenses. One doesn't change lens boards: it's easier and faster to unscrew the lenses. Minolta supplies a special series of enlarging lenses which offer both click stops and continuous diaphragm action. More about that when we talk about the Minolta Color Analyzer.

In use, the Minolta Color Enlarger Model-I proved to be well-designed, solid, and of extremely high overall quality. Pulling a lever on the left side of the lamphouse raises all three modules as a unit, allowing insertion of the carrier. The carrier is made of two pieces of heavy aluminum plate which are anodized jet black, hinged and spring-loaded, so the carrier stays open until the weight of the lamphouse closes it. The negative is positioned by four pins. To change a negative, just take off the weight of the lamphouse by pulling the left-hand lever. The carrier and the negatives can be slid with no danger of scratching. Good finish and precisely-machined apertures on both top and bottom plates indicate careful workmanship. Guides on the lower side of the bottom plate make for fast, accurate carrier insertion.

Let's examine the enlarger in terms of performance. Alignment between negative, lens and baseboard was as perfect as we have ever seen. The difference between the three planes was so small that it was unreadable on our alignment tool. And considering the massive construction of the Minolta enlarger, it is our opinion that the alignment should remain accurate throughout the life of the machine. Evenness of illumination was checked with our Lektra PTM-7a photometer with the enlarger in both 6x7 and 35mm modes. In each case, the enlarging lens was stopped down to f/16 to ensure that any fall-off was not a function of the lens, but a true measure of the enlarger's optical system. In the 6x7 mode, illumination was within 1/10 of a stop from center to edges, and the difference between edges was so small as to be unreadable. In the 35mm mode, the edges differed from the center by about ¼ stop, and no discernible difference existed from edge to edge.

Temperature measurements at the negative plane were made over a period of 10 min. While we usually record the data in tabular form, there is no point in this case. Temperature readings started at 22°C and never reached 23°C. We rate this machine as the coolest running we have encountered to date.

Printing times, using our standard negative to produce an 8x10 print on Polycontrast Rapid (no filter) at f/11 ran 40 sec. That's pretty slow compared to other machines we have tested. Although no reciprocity problems arise in B&W work. Modern's editors feel that a more powerful light source would help speed things up considerably.

Before going on, we have one more point of criticism. To change from 6x7 to 35mm and back again requires that two knurled screws be removed, each module lifted out, the mixing boxes changed and the unit reassembled with the knurled screws replaced. It takes longer than we would like. We ended up leaving the screws undone. But some sort of faster-acting fastener is called for to speed up the changeover process.

Now let's change modular parts of the enlarger. We'll remove the Mod-I filter drawer module and replace it with the Mod-II dichroic filter module, thereby changing the enlarger over to a Minolta Color Enlarger Mod-III. And here's where the advantages of Minolta's unique design become apparent.

With previous designs, to convert an ordinary enlarger into a color enlarger you have to change everything above the negative carrier. A color head is needed consisting of a light source as well as dichroic filters. The Minolta only requires that the dichroic unit be inserted; the same light-mixing boxes and light source are used. And a beautiful little dichroic module it is. The construction is almost jewel-like. The cyan, magenta and yellow dichroic filters are mounted in cam-controlled plates. As the controls are turned on the front of the module, a geared rod is driven across a long screw, bringing each filter into the light path. A hinged lever allows all filtration to be instantly removed from the light path. The Minolta dichroic unit has large legible numerals which are well-illuminated and easy to read in the dark. Filtrations from 0 to 150 (153 to be precise) in cyan, magenta and yellow are marked in increments of .01CC.

For the first tests, we used our Kodak Ektacolor Standard Negative. Prints were made on Ektacolor 37 RC paper processed in Kodak Ektaprint 300 chemicals on a Kodak Rapid Color Processor Model II which was temperature-stabilized. The filtration to match our standard test print was 123Y + 42M. For an 8x10 print, the exposure ran 18 sec. at f/8. Not bad. But when we switched to a slightly denser negative that was well within the range of "normal" negatives one might be expected to handle, exposures ran to 40 sec. at f/ 5.6--dangerously near the 60-sec. reciprocity limit--and a fairly wide aperture. To the man buying this machine, Modern's editors recommend care in keeping negatives in the middle range of normal densities. To the designers, we say, "Get a bigger light source!" The print quality was excellent with good color saturation and contrast, indicating efficient heat-absorbing glass and 2B filtration.

Now for the final and most important modification of all: the addition of the integrated Minolta Color Analyzer. If you are visualizing a standard box with three knobs, a dial and a probe that sits next to the enlarger, forget it. That's not what this is. The Minolta Color Analyzer is tuned for the Minolta Enlarger only . . . unless, of course, you want to make extensive and costly modifications on some other machine.

The analyzer consists of three basic parts: a probe, an analyzer lens board unit, and a meter module. The meter module bolts onto the left side of thelamphouse with three knurled screws. The regular lens board is removed and the analyzing lens board is bolted on in its place, using four screws. The probe is hung on a bar on the left side of the meter module, well out of the way. Plug the analyzer's power line into the keyed outlet on the power supply and you're set to go.

Before we start to calibrate the system, let's put it into perspective in terms of other analyzers. Basically, most analyzers work through a probe which contains photomultipliers that do the job of detecting cyan, magenta and yellow right on the baseboard. We can use these units to read a flesh tone or gray card, or take an integrated reading by scrambling the image with a ground-plastic disc. This type of analyzer can be used with any enlarger and is an accessory rather than an integral part of the enlarger. The Minolta Analyzer is different. It has its cells located in the lens board facing the negative, and it makes an integrated reading only. The scrambling is built in, so all decisions and options of what to read or calibrate no longer exist. Versatility is traded for one totally worked-out operating method which becomes an integral part of the enlarger. From a certain point of view, it makes sense. Most photographers never include a neutral gray card in the scene. In addition, many scenes, such as landscapes, contain no flesh tones. In these circumstances the integrated or scrambled method is the only alternative. From this point of view, we can't fault Minolta's designers for having chosen this one option.

Now. back to the analyzer. Do you remember that test negative that required a filtration of 123Y + 42M with an exposure of 18 sec. at f/8? Well, we can now use exactly those conditions to program the analyzer. We switch on the analyzer, turn off the room lights, and check to make sure that the filtration and aperture are properly set. Now we go to the analyzing lens board. Turn the channel-selector knob until the letter "C" (for cyan, of course) appears in the illuminated window at the rear of the lens board. Now turn the cyan control on the meter module until the needle nulls. Switch the channel-selector knob to "Y" for yellow. Now go to the top of the meter module and set the yellow programming knob until the needle on the meter module nulls. Repeat for magenta. The unit is now programmed for color. Now let's program for exposure. To do that we switch the channel-selector knob to "E." Now comes a problem--not with the unit itself, but with the instruction book and the working philosophy of those who designed this system.

The book says: "Move the probe until the reading spot is beneath the projected image of a fully lighted significant subject tone." We know what is meant by this. It means a flesh tone, or grass, or anything that will consistently appear in the negatives to be printed. There are a number of problems with this approach. First of all, it requires that you take a good guess from negative to negative, looking for tones that are of the same value as those in the test print. Well, if you're going to guess, what do you need a meter for? Besides, Minolta's decision to go the integrated route for color compensation was based on the assumption that a flesh tone, gray card or any other reliable standard won't always be available. So how can they base the exposure system on it?

We have a simple and surer answer: just scramble the exposure reading. All that is required is a piece of matte plastic over the lens. You place the probe on the easel. Then set the exposure-programming knob until the needle on the meter module comes to 18 sec. Now the machine is programmed. Put in a new negative and run through the procedure backwards, changing the filtration to null the meter and stopping down to get the desired exposure. Fast and simple.

In use, we found all the controls-easy to operate and relatively handy. The meter-module dial was rather dimly lit with no control to brighten it up. We had to stoop to see the markings on the analyzing lens board: they were small and also somewhat dimly lit. The new Minolta Rokkor-X lenses were designed with click stops which can be converted to continuous movement by pulling down the diaphragm ring. Very clever and necessary when a desired aperture falls on the shoulder of a click stop and the setting can't be held.

Overall, this is a first-class machine. The basic concept of the integrated analyzer is a step forward for the man who wants things simple. The designers are to be congratulated for an imaginative product, and the engineers for excellent execution. It's a welcome addition to the spectrum of color enlargers available today, and may well set new standards of design for the color enlargers of the future. Certainly, any enlarger manufacturers planning a modular unit will take a close look at this Minolta.

Minolta Color Enlarger II

The following appeared in the now-defunct Darkroom Magazine, Vol 3 #8 (December 1981). It was written by Robert Holmes. It has been lightly edited for brevity.

Because I have never really associated the major Japanese camera manufacturers with darkroom equipment, it came as a bit of a surprise to discover a new enlarger from Minolta. An additional surprise was that although Minolta now only manufactures miniature format cameras, their Color Enlarger II accepts all formats up to 6x7. The original version of this machine apparently never gained much of a foothold in the American market, so I was interested to see what the new model had to offer. It lists at $400 but as this price includes a dichroic color head (in fact, there is only a color version made), it is in a reasonably competitive price bracket.

It comes with a strong nonwarp baseboard measuring 18 x 24-1/4 inches with a white stain and moisture-resistant finish. Onto this is attached a 35-1/2-inch-long column by means of four bolts. This column has a luminous elevation scale calibrated in centimeters plus magnification settings for 50mm and 80mm lenses.

The lamphouse/color head unit slides directly onto the column and connects to a counterbalance in the column. Illumination is of the standard diffusion type, using a 150-watt ESD halogen lamp. The color head houses continuously variable cyan, magenta, and yellow dichroic filters providing up to 150 units of cyan and magenta filtration and 200 units of yellow. The critical alignment of optical components, color head, and column is factory calibrated.

As with any photographic equipment, you get used to your own enlarging gear and new equipment often seems a bit strange and awkward to use. However the Color Enlarger II seemed familiar right from the start. All the controls come easily to hand. An oversized elevation control can be operated with one hand. Depressing the control frees the counterbalanced carriage, allowing it to travel effortlessly up or down the column. Releasing the control locks the carriage firmly in position. A large grooved focusing knob on the right-hand side of the Tens panel makes pinpoint focusing quick and positive. I have been using the enlarger now for several months and there has not been any detectable play in any of these controls.

Three large knurled dials are located on top of the color head to dial-in the stepless filtration. The amount of filtration is indicated in illuminated windows on the front of the color head. I regret the absence of a white light lever; to get white light all three dials have to be returned to zero. This is aggravating if you are switching between color and black-and-white printing and use a standard filter pack for color. I suppose the argument is that this is specifically a color enlarger but even then, if heavy filtration is needed the lack of a white light lever can make focusing rather difficult.

There are nine negative carriers available, five glassless for 16mm up to 6x7, three glass carriers for 35mm, 6x6, and 6x7, and a 35mm mounted transparency carrier which, with the growing use of Cibachrome and reversal papers, should be very popular. All the carriers are very finely machined and if looked after should not scratch any negatives. Negatives are held firmly on all edges and although the carriers are of a very simple construction I have not had any problems with negatives buckling even in the 6x7 glassless carrier.

The lensboard is a standard 39mm Leica screw thread and I used both the Minolta CE Rokkor 50mm f/2.8 and CE Rokkor 80mm f/5.6 enlarging lenses in my tests. The 80mm lens covers the 6x7 format without any vignetting. These are fully corrected six-element lenses giving an optical performance as good as any enlarging lenses I have ever used, even at full aperture, and with no noticeable focus shift when stopping down. A feature I particularly like is the illuminated f/stop ring, a design almost identical to the superlative Rodenstock enlarging lenses. Magnifications on the baseboard are up to 13.3X with the 50mm lens and 6.8X with the 80mm.

For larger magnifications the enlarger column has to be reversed to project onto the floor. This is both inconvenient and limits enlargement size to your bench height. This enlarger can make giant enlargements but you really have to want to make them! Similarly, there are no swing or tilt controls on the head to enable corrections to be made to negatives. However, the lack of head movement results in a very solid, vibration-free unit which is likely to retain critical alignment longer than many apparently more versatile instruments. It also means that the enlarger head spills very little light. The only spillage comes from immediately around the negative carrier but this is too insignificant to result in fogging even on long exposures.

I have used the Color Enlarger II for both B&W and color printing for prints up to 16x20 and have found it a delight to use. The light output is high enough to allow less than 15-second exposures at f/8 for 11x14 Cibachromes and all controls are both smooth and reliable. With the enlarger I used the accessory Minolta Stabilizer II because I consider a voltage stabilizer to be absolutely essential for consistent color printing. Unlike some other stabilizers I've used this model is wonderfully quiet; its hum is almost imperceptible.

One other gadget that I had the opportunity to play with was the Minolta Color Analyzer II, a compact, spot-type analyzer for determining filtration and exposure for color negatives or transparencies. It is a single "on-easel" unit with two programmable memory banks to store color analysis for later recall. Programming and analyzing is accomplished by matching the brightness level of two green LEDs. A red LED warning signal comes on when the brightness of the projected image is insufficient to make a proper reading. An optional diffuser is available for averaged readings but I feel that this defeats the point of using an analyzer in the first place.

If all the above sounds straightforward, try reading the instruction book, which will make you think otherwise. It may be a mental block on my part but with most analyzers I feel you need a degree in computer sciences before you are able to program and use the thing. The Minolta Color Analyzer II is no worse than any other in this respect and in use certainly gives reliable results. But for most amateur and even professional use, I question the usefulness of these gadgets. Each new batch of paper has to be analyzed as does each type of film. If you always print from the same film stock and can afford to buy large quantities of paper with the same batch number, then an analyzer may pay for itself. But for the rest of us, I think the money would be better spent on a few more boxes of paper.

I'd say the Minolta Color Enlarger II is a good basic color enlarger without any frills that will provide for 99 percent of most people's printing needs. It's a solid, high-precision product that should give years of trouble-free service. I only wish it handled 4x5 negatives!