Leica User Forum - View Single Post - Exposure Latitude Question -- Tri-X v. T-grain films

R.Morrison · 05/03/08, 05:19 PM

PATB:
I do not agree that T-Max requires less accuracy for metering. Quite the contrary, both Tri-X and Plus X have greater latitude. Why is this so? Because Tri-X and Plus X are old technology films with irregular grain sizes in the emulsion. This means that the small grains in the emulsion will react to light rather quickly whereas the large grains react more slowly. This means that you have the emulsion reacting at both ends of the exposure scale thereby giving greater latitude. The penalty however will be greater graininess. T-Max on the other hand has uniform grain in the emulsion. All crystals will react to light exposure at the same time thereby requireing greater metering accuracy. The bonus will be finer grain with a commensurately greater ability to enlarge.
Since you do your own developing (as do I) you might find the old technology films to be more forgiving with respect to times. If using an old technology developer such as D76 you might find T-Max getting a little contrasty if you are a little slow in getting the stop-bath to it.
Kodak has formulated a special developer for T-Max films. USE IT! While many do not like T-Max developer, I do. I find that T-Max will exhibit far less grain when used in the developer dedicated to it and minimising grain is of course the reason for using T-Max in the first place.
Frankly, if you are over or under by only one stop, Tri-X, Plus X and T-Max will produce excellent results at normal exposure times. Experiment a little. They are all good and you will find a personal favourite. Mine is Plus X (ASA 125) because, though it exhibits more grain than T-Max 400, the tonality (especially for flesh tones) is fantastic.

R. Morrison, M4-P, etc.

05/03/08, 05:19 PM	#4 (permalink)
R.Morrison Benutzer Join Date: 09/04/06 Location: Iqaluit Posts: 97	Re: Exposure Latitude Question -- Tri-X v. T-grain films PATB: I do not agree that T-Max requires less accuracy for metering. Quite the contrary, both Tri-X and Plus X have greater latitude. Why is this so? Because Tri-X and Plus X are old technology films with irregular grain sizes in the emulsion. This means that the small grains in the emulsion will react to light rather quickly whereas the large grains react more slowly. This means that you have the emulsion reacting at both ends of the exposure scale thereby giving greater latitude. The penalty however will be greater graininess. T-Max on the other hand has uniform grain in the emulsion. All crystals will react to light exposure at the same time thereby requireing greater metering accuracy. The bonus will be finer grain with a commensurately greater ability to enlarge. Since you do your own developing (as do I) you might find the old technology films to be more forgiving with respect to times. If using an old technology developer such as D76 you might find T-Max getting a little contrasty if you are a little slow in getting the stop-bath to it. Kodak has formulated a special developer for T-Max films. USE IT! While many do not like T-Max developer, I do. I find that T-Max will exhibit far less grain when used in the developer dedicated to it and minimising grain is of course the reason for using T-Max in the first place. Frankly, if you are over or under by only one stop, Tri-X, Plus X and T-Max will produce excellent results at normal exposure times. Experiment a little. They are all good and you will find a personal favourite. Mine is Plus X (ASA 125) because, though it exhibits more grain than T-Max 400, the tonality (especially for flesh tones) is fantastic. R. Morrison, M4-P, etc.