Tri-X film was one of greatest film ever produced I believe. Many BW photographers until the end of film era loved to work with it, no matter
how many new films developed later. Even, its maker Kodak could not replace Tri-X with newer & better TMAX-400.
Making BW film preset is not difficult but how it express feeling in BW way, is the key at the end.
In the beginning I tried to copy Tri-X characteristics as much as I can, starting from silver density curve and light sensitity of emulsion
(color slide bar in S/W). But after many trials and errors, I realized it is very difficult to copy chemical characteristics to software driven tool.
Moreover it is NOT necessary to do so.
S/Ws such as SilverEfex, LightRoom, DXO film pack, Photoshop have their own characters, so how precisely copied from film characteristics,
they are not equally reproduce the output, Tri-X film look, anyway. In other words, there is NO fixed defintion of Tri-X film look at all unless
you use the film itself. What really matter is the ‘metaphor’ of Tri-X film instead of dead copy of their curves, to reproduce ‘feeling’ of the Tri-X.
In short, it is matter of Tri-X photo, not Tri-X film.
Pre-requisite and direction
All film presets need a expression of grain, and it is the key point of any ‘Film Presets’. Tri-X in real world has 2 distintive characteristics.
(1) Coarse grain / harsh tone – 135 type Tri-X film has ISO400 sensitivity and shows coarse grains even though not coarse like ISO1000 or up.
It shows a little harsh and often lack of details in shadow or in dark tone. It is not because of this film itself but how it used mostly. In 35mm street
photograph where the film’s higher sensitivity appreciated, photographers tend to set ISO800 or more to maintain workarble shutter speednd
theb do push develop later.
(2) Fine grain / full tone – 120 type and 4X5 sheet Tri-X film have ISO320 which indicates they are not the same film with 135 type even though
they bore the same trademark. There is variance on production to differentiate their characters.
In 120 and 4X5, grain is not major or distinctive factor because of large film area. This film often used in ISO160 to make it better.
1 stop over exposure ensures shadow details recorded properly, rendering beautiful black tone and also have good details.
Highlight details can be maintained without wash out if developing time reduced about 15%. Tri-X react very well to this kind of push-pull control
so called N-2, N-1, N+1, N+2.
Other films which have thin emulsion do not respond push-pull develop well and sometime shows dull grey tone, the least attraction of BW photography.
Deep black with good details and medium black with full of local contrast and sharpness is the distinctive characteristics of Tri-X, attractting
photographers so long time. Does it mean ISO400 Tri-X film have different character from ISO320 Tri-X? YES it has.
But in film photography, film area is more dominent factor than film itself to show a certain characteristics.
(3) Grain coefficient in digital S/W – LightRoom and SilverEfex define grain as ‘amount / pixels’. It means 12M file will show different result from
6M file or 24M file if the same coefficient used. Therefore preset has to be made specially for a certain pixel size, in here I will make 6M, 12M, 24M
and 36M to have the similar result (same look) in final resized image. I also make them for ‘screen’ not ‘print’.
In summary, ‘metaphor’ expression of Tri-X does not mean copying Tri-X film characteristics in S/W. It is reproduction of ‘feeling’ of Tri-X photo.
Harsh tone in coarse grain in some street photography we’ve seen and deep / smooth tones in large format landscapes, those are the final goal
of this BW preset projects.
- The slope of Tri-X is stiff compare to others, thus increase the contrast through S-shape curve.
- I consider slight cut off at left most (Zone 1 area) to emphasize a harsh tone, but in this proto setting I left as it is. I will try ‘cut off’ version later.
- Reason the curve is not centered is to increase overall exposure. Good exposure in color (mid tone) is often too grey in BW, hence 0.5 to 1.0 over exposure will benefit in BW post processing.
Color response :
- Film Emulsion characteristics: Film did never react to color light evenly. Depends on emulsion type it react to a certain wavelength more or less.
- In here, I adjust color light sensitivity based on reference from Silver Efex’s pre-definition, increase Yellow, Red slightly and redcue Green some.
There is (almost) no case to finish post processing with simply applying preset.
It is better to say preset is a good starting point for post processing. It is more like time saver using automation for repeating post processing steps.
Presets need to be made for camera types if Raw / JPG renders different characteristics.
Modern digital cameras in real case do not show much different results, butt CCD / CMOS sensors show significant different result, thus requires
different presets. For example, Kodak 645M (CCD sensor) and Rocoh A16 (CMOS sensor) have the same 16M size pixels but show very different
result the same preset applied.