Response to Alternative to Xtol

Microphene unfortunately does not give any speed increase. My measurements with a densitometer show that it is hardly possible to change effective film speed with different developer formulations. With a few exeptions the speed will stay about the same when the negs are developed to an equal gamma. That some developers increase effective speed is one of the big urban myths fostered by the manufacturers of photo chemicals obviously to improve sales. In most standard developers the effective speed of most films is about half the speed that is printed on the box, often even less (exception is Efke, which is very close). Especially high speed films are "off" quite a bit. The manufacuters deliberately accept loss of shadow detail and many photographers accept this loss as desired "look" of a specific film. Examples for this are Ilford HP5, which -- according to ISO specifications -- would have to be rated around ISO 320 in many developers. Microphene will not alter this speed rating at all. The higher the film speed, the more "off" films are as a rule of thumb. The developing times stated on the box take this into account and what you do when you develop the film is already push processing in many instances: The developing times were adjusted according to midtones, not according to overal contrast and not according to shadow densities, which affect film speed. Since high speed films are generally softer than low and medium speed films they take a little more abuse in exposure but still the overal contrast rendition will suffer from this. The film will generally be "harder" than it ought to. This brings us back to underexposed negs. If the film was shot -- lets say -- with ISO 800, although the box says ISO 400 than we have an effective underexposure of 2 f-stops, not one. There is no way of compensating for this with maintaining full shadow detail. Shadows inevitably will have to go when the midrange contrast is being built up. There are two differing strategies now: (1) Active developer that can achieve high densities. I had suggested A49 for this before. A49 will easily push the midrange densities back into place, but the contrast will (as always in push processing) be much higher. People often underestimate this phenomenon. If the gamma was 0.7 using "normal" development (to use this as example), than a one f-stop push will get you into the 0.8s or 0.9s and a two stop will get you in a gamma range of 1.x and higher. There is no paper grade that will print this neg with full spectrum if a scene with average contrast was recorded. If the scene recorded was low contrast A49 still is an excellent solution. (2) The second strategy is to build up midtone contrast and somehow restrict the overal contrast buildup especially in the highlights. 2-part developers can limit the highlight contrast effectivly. There are better and worse products and published formulas out there. The best I have used so far is Tetenal Emofin, a widely used developer in Europe. This developer is based on colour chemistry and will achive extremely fine grain without rendering the overal tonal rendition too soft, which often is the case with very dilute developers. Unfortunately this product, which has been extremely popular with professionals in Europe for decades, is not available in shops in the US, but it can be ordered easily through mail order companies such as Fotoimpex. Emofin is more expensive than some other developers (around $8 per quart), but it will develop 17 films or more, which makes it very economical. In comparison with Acufine the grain is finer and the acutance -- usually a problem with 2part developers -- is not bad at all. The base fog, which necessarily is higher with 2part developers, is no problem. It is only minimally higher and you just print through it. Although even in this super fine grain formulation the grain will noticably get higher with push processing, but a compensation of up to 2 f-stops underexposure are possible without too much contrast buildup.

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