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Heiland Splitgrade LED Module for Leica Focomat V35 AF

Long ago people used the darkroom, not because they liked the idea, but because it was the only cost-effective way to have their negatives printed on a decent size of paper. You were photographer, not a darkroom expert and with the exception of a handful of fine-art printers and zone-system enthusiasts, the darkroom was a place to be avoided. There has always been a core of photographers who wanted to have mastery over every step of the photographic process. Since the full digitization of photography from capture to distribution, every one can be a master of the photographic universe. A plethora of ink-jet printers is available for the case that one wants to have a true print and Hahnemühle or Caslon are now the household names in the daylight room that once AGFA or Oriental were in the darkroom. The debate which process could yield the best result has been closed with a firm ‘undecided’. From a technical standpoint a fine darkroom print and a fine inkjet print may be equals, and when large-sized prints are required (say significantly larger than A4) the digital workflow wins hands-down (because of the degradation effect of light scattering in the silver-halide emulsion). From a qualitative and may I add an emotional view the silver-halide print has a visual impact that the digital print simply lacks. It is not by accident that Nik with Silver Efex and DxO with Filmpack have two programs that emulate the quality of the subtle shades of grey (at least much more than fifty!) that the irregular grain pattern can produce.
Darkroom prints from standard 35 mm Leica negatives are limited to a size of A4 and at most A3 to have strong visual impact and high technical quality (excellent sharpness impression (also known as acutance) and a just perceptible grain pattern for three-dimensional reproduction of fine textural detail). One of the main rules for Leica pictures is the optimization of the negative area, not wasting the edges of the image. The 2:3 proportion of the negative however is difficult to match with the 3:5, 3:4 and 4:5 proportion of many printing papers.

Below: an overall view of the Splitgrade system for V35


The creation of a good print with maximum black and silvery highlights (the area where inkjet prints still confront their Waterloo) is not easy given the considerable influence of a number of variables. Ansel Adams wrote a thick book that only explained the basics! Finding the exact exposure time to get maximum black without clogging the shadows, and selecting the correct paper gradation for a given negative density range was and is a time consuming experience and one that has to be repeated for every size of enlargement and paper choice.
Most papers used in the darkroom are of the variable contrast type. VC paper is composed of two different emulsion types in one layer, one sensitive to green light (soft gradation) and one sensitive to blue light (hard gradation). With a yellow and a magenta filter or a mix of both we expose one or both emulsion types for a certain time. The yellow filter blocks out the blue light and so exposes the green sensitive layer. The magenta filter blocks out the green light and so the blue sensitive layer is activated. All VC modules use a light box to mix the blue and green colors for one exposure. The specific mix corresponds to the grade 0,1, 2, 3, 4 and 5.
The Heiland Splitgrade system has been designed to take the guesswork out of the darkroom practice. The designers call this device a grade management system. The core of the system consists of two parts. One is the VC module which will replace the existing VC module of the enlarger. The module has two separate filters, one for yellow and one for magenta, that are placed into the enlarger light. The paper then is exposed twice, once for the yellow filter and once for the magenta filter, the relative proportions being computed by the system and corresponding to the grade selected. This method of split-filter printing is well-known by fine art printers who need the utmost and precise control over the printing. It provides for better local contrast control, finer differentiation of grey tones and more richness of detail.
The second and most ingenious part of the system is the controller. The device looks like a timer. But it has a chip built into it, comprising all exposure and contrast data for many current papers. These are not the well-known characteristic curves for every grade as published by the industry (increasingly rare by the way). No, it are the test results of the Heiland people, achieved after many months of testing and densitometer readings to search for every modulation in grade and tonal values and exposure time, related to the split grade technique. This unique database of densitometer readings is the heart of the system.
Attached to the controller is a sensor, that measures, as any densitometer would, the density of the negative areas. Just move the sensor randomly over the negative area. It will remember the intermediate maximum and minimum values and so will eventually find the true max and min values. If you have more experience or the negative is very challenging, you just locate the min and max values for yourself and measure these. These values then give the density range of the negative. The computer then computes the grade and the exposure time, related to the chosen paper. These three readings (paper type, grade and time) are displayed in the display and could be changed. The user here has full control to change whatever he likes. The software is programmed in such a way, that whatever paper or grade is chosen, maximum black is reached in every situation. Any Zone System worker will remember the laborious work to find the SAT (minimum exposure to get full black) which changes every time when the enlargement factor changes. Now it is all programmed in a chip and readily available.

The original Splitgrade module consists of a moveable disc with holes for white, yellow and magenta filters that are selected and timed by the controller. The original lamp unit is used to expose the paper. The light source has the habit of dying just when you are in the middle of a darkroom session and even if you have a replacement unit, it is not a pleasure to change the bulb. And there is an unevenness of exposure from centre to corner that may or may not be useful for the overall negative illumination.
The new LED version of the Splitgrade unit for V35 does away with the original light source and the moveable disc and replaces both with one LED unit that consists of three LED units (blue, red, green) that can be used individually of in combinations to produce red, yellow or magenta colors. There is also an improved controller unit that is smaller, has a USB connection and a larger memory unit plus a range of improvements in handling and efficiency. See below the general layout. Note that I also use the Comfort module: very easy to use and an improvement for overall handling.

The new LED unit, replacing the original light source and the filter box. The intensity of the LED source is equal to that of the original light source (Philips 12V/75W), but the heat generation is only a fraction of the original (25%). This helps to keep the negative completely flat if you use the light for a prolonged period. There is a cooling unit that makes an audible noise, but it can be switched off when you do not use the unit for longer periods. The additional advantages are: no moving parts and more reliability, stable light source from the start, even illumination from centre to edge, light source has a life span of several thousands of hours, and the lamp house stays cool. The workflow is very simple: a longer pressure activates the white light for the measurement. The white light has a much bluer tint that the original light source, and this colder light gives a different impression of the negative. After some time you are accustomed to this.


The working steps are the same as usual: position the sensor to the negative areas where you want shadow and highlight detail and accept the proposal of the controller for gradation and time. A short pressure on the controller top-button activates the red light and now you can position the selected print paper. Exposure times are rather short and the choice of gradations has shifted a bit to the lower grades, presumably to accommodate for the quality of the LED light. The results are excellent. With the standard 1.5 minutes development time (Ilford Cooltone developer in my case) you get deep blacks (density 2.02 without any adjustments) without blocking the differentiated shadow detail. The middle grays are very finely separated with very subtle tonality. The highlights are very well differentiated and it is here that the reflection value of the silver-halide surface goes one better than the inkjet print. The density of the blacks in the inkjet print is slightly higher with 2.10, but the black areas are a bit wooden and lack the intensity of the silver-halide print. Presumably one can improve the inkjet print somewhat, but then the time investment and paper waste is much higher than in the case of the Splitgrade system whose results are hardly improvable with manual input.

The negatives used are Ilford Delta 100 developed in Spur Acurol-N (see the separate report) and printed on ADOX 310 paper (very close to the classical AGFA MC Premium). The time spent in the darkroom for ten A4 prints is about 45 minutes (excluding the time for putting out the trays with the chemicals. This period compares very favorably with the time spent in front of the computer to produce prints with the Epson 3800. In this case the digital workflow is more complicated and time consuming than the chemical one and the quality of the chemical print is second to none with the additional emotional value of handling ‘the real thing’.
The LED Splitgrade unit for the V35 facilitates the work in the darkroom and produces outstanding results. I do not have the illusion that the darkroom practice will become the prevalent method of black and white printing. If you ponder the idea of going classical with, let us propose, the Leica M6 or MP and want to follow all steps from negative development to final print, this might be the moment to step in the wonderful world of silver-halide. This experience will certainly help you to optimize your photography with the Leica M Monochrom. Basically this is a good argument for working in both worlds and enjoying the benefits and advantages of solid-state and silver-halide capture. Your photographic experience will be enriched when you are able to change comfortably from one workflow into the other. Enjoying different meals improves your taste, does it not?
It is the attitude of the day to be focused exclusively on matters digital and to look with disdain at the poor guys who have not seen the light and continue to slog away at the silver-halide technique. As in politics it makes sense to cultivate a bi-partisanship. One might even say that technical relativism is an element of a cultural sophistication that is currently lacking in the photographic world
If you already own the original Splitgrade system, you may consider an upgrade. Work in the darkroom has never been easier and more pleasant. It is easy to stick one’s head in the sand and believe that silver-halide photography will make a come-back, like the current boost in the sales of gramophone discs. I am afraid this will not happen.The promotion of the use of silver-gelatin as a photographic medium is however intimately connected to the style and culture of Leica photography, a fact that the company does not seem to appreciate anymore. It has always been my approach that the method and technique of digital capture should emulate the silver-halide processes (from negative to print with minimal post-processing). In this I am old-fashioned because I propose a theory of photography that for some prominent observers in the field is obsolete. That being so, working with film and the darkroom exposes one to an experience and branch of knowledge that is becoming a photographic heritage. The new Heiland Splitgrade System supports this photographic culture in an admirable way. The list of supported papers is up-to-date and comprehensive. The Heiland LED Cold light unit is available for a range of enlarger types and can be used also without the Splitgrade controller. See the website for details.

Below a small section of the full negative area. Just select a highlight and a shadow area. Print as it is.